Roman Posted November 29, 2017 Author Share Posted November 29, 2017 Okay so after I finished building the MAF curve, and drove around to collect some data with it, and then I started building a fuel table using MAF as load axis. After plugging away at this for a while, I noticed something interesting - The fuel map becomes just a straight slope all the way across haha. So this is what my basemap looked like: And the car drove awesomely on it! After a few tweaks to the overall shape it's still pretty similar. Definitely a lot more linear than a MAP or TPS based tune. Which makes sense. With a MAF based tune you really do need some decel fuel cut, as when you shut the throttle the MAF value momentarily climbs and you get pops and bangs out the exhaust... Oh the humanity! In less awesome news though, this new gearbox seems stuffed. The synchros in 3rd seem non existent and I think I heard it break something when I hoofed it into 3rd today haha. So no OS drags for me in this car, and no trackdays this year either. sadface. WTB (non fucked) Altezza gearbox if anyone sees one for sale. EDIT: Also I ran over something with my AD08Rs on which put a big gash in one of my tyres as well. Blargh. 4 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted February 7, 2018 Author Popular Post Share Posted February 7, 2018 Welcome to...The Age of Enlightenment One of my favourite things about... stuff... Isnt just making something but also optimizing it however possible.Kerbal Space Program is a good example, of the benefits of optimizing things. (You build space ships) You can have a ship that works well, but then doing things like reducing the amount of fuel in each container to just how much you need for that particular stage of your rocket, reducing thruster power to the optimal speed to minimise drag, and so on. Can make a ship that looks the same massively faster and go massively further. In terms of how this relates to my car, currently its at the point where I've just slapped some shit together and seen that it works, which it does. But some things suck for a variety of reasons, or are okay but could be better. It could benefit from some time spent optimizing stuff. For example, I have these fucken massive vented rear brakes, which I then need to use a bias valve to turn them almost completely off in order to not lock up the rear. Do I really need a 5kg vented disc on each side of my live axle, and a big steel caliper that's probably about the same? Probably not. Switching to an aluminium MX5 caliper and a non vented disc, I can drop a fair chunk of unsprung weight annndddd my brake bias will actually work better. Cool. My goal is to lighten the car in a way that doesnt make it any less useful as a street car, or any less useful on the track. I want to try and get somewhere into the 6 litres per 100km mark, do a 13 second quarter and do a sub 1:20 laptime at Hampton. Making the car lighter helps work towards all of these goals. So essentially my plan is to just make a lot of tiny iterative improvements everywhere, (Which may seem like a waste of effort when viewed in isolation) that will add up to a bigger picture change. (Maybe). And learn some some new stuff to stave off insanity a little longer and keep my brain ticking over. Before I started doing anything I weighed the car with approximately a quarter of a tank of gas, full interior, all of the seats, etc. Came in at 1020kg without driver. So it will be super easy to get it under 1000 and I think closer to 950 or 900 will be achievable. So here are a few things on the to do list: -Swap in dual VVTI engine, (for better fuel economy thanks to exhaust side VVTI, and more power thanks to slightly higher CR) -Swap to the 2NZ Alternator which saves ~4kg for same amperage. -Cast some aluminium engine mounts instead of the steel ones with sloppy old rubbers. -Downsize rear brakes. -Remove blower assembly, heater core etc from under the dash as none of it works particularly well and it's quite heavy. (done) -Depending on how engine mounts go, possibly cast an aluminium gearbox xmember as well. (I will 3d print a shape for the local foundry to do these) -When I had an oil cooler, when I had the oil cooler fan going the radiator fan NEVER needed to come on. Even on a hot day. Since there's a water to oil cooler on the engine, I've removed my oil cooler and my large radiator fan. I have put the oil cooler fan on the part of the radiator with the highest temperature differential (Right by the top hose) and surprisingly enough the car doesnt overheat with this tiny fan. Even on a hot day. Which leads me to... -Remove the radiator fan entirely and use a radiator sprayer bar. Since I need a washer bottle to spritz the window for WOF, I can have a valve on it which uses the water to mist the radiator instead when needed. Currently its only in stop start traffic or moments below 35-40kph where needs the fan at all. Also, at high speeds where a fan cant actually assist to cool your car, evaporative cooling can. (Still tossing up this idea but it sounds fun to experiment with. Will leave fan in place as a backup while testing) -Remove rose jointed t3 Castor arms, and go back to standard ones with stiff poly bushings. The weight difference is ridiculous and I'm not convinced they're particularly better than standard configuration. -Remove the rear muffler and cast an aluminium rear part of the exhaust pipe that has a butterfly in it which I can control with the ECU. This has the benefit of making the car a lot quieter when cruising along, annnddd, I can introduce pressure to the exhaust system in order to increase EGR effect of VVTI at cruising conditions. Which I believe may help improve fuel economy, as counter intuitive as it may sound. -Reduce idle speed as low as possible to save fuel (Already done) With MAF based tune I can now get a stable ~670-700rpm idle, but I've used a few tricks to make it more drivable and not stall. Such as increasing goal idle speed above 5kph and when the engine is cold. -Find a way to optimize cam timing at cruising conditions for best economy. This one has been on my mind for a long time, it seems very difficult to quantify how to best set the cam angle. So I have been working on an arduino based canbus project which can communicate to the ECU and show a live fuel economy value. I can turn knobs on the box to increase or decrease a trim table that affects cam timing, fuel, ign, or injector timing, or whatever else and get within ballpark this way. For version 2.0 of this, I am planning on having a closed loop ignition timing control that turns on when cruise control is active. It will float the ignition timing a few degrees eithe way, find the most economical value and then update a trim table in the arduino. Work in progress... I'm also considering having an overlay trim table in the ECU that changes ign timing based on current AFR seen at the oxy sensor - A leaner mixture needs significantly more timing. So it can do this dynamically. -3D print all the things! Lately I have jumped on the 3D printer bandwagon, and this will be an elemental part of the process for some of the stuff above. Not only can I print PLA prototypes, or ABS/Nylon functional parts. But I can also make molds for making other parts out of fun stuff like Polyurethane or Carbon Fibre. I made a test mold to see how Carbon Fibre would work and it turned out friggen awesome: So I'm going to make some more carbon parts, it's such a fun process and seeing the results is exciting. Stuff is so strong and so light, cant wait to make some more stuff out of it. -Digi Dash Tying into some of the above (3d printing a new dash housing, and using ARduino knowledge to build the screens) I will put together a canbus based digidash that will be cool. Will try and make it look like an 80s spec digidash as much as possible, but also have some context sensitive functions in it. (So screen will show different values when cruise control is on, or if you are at a trackday, or whatever) This isnt strictly something that makes the car better, but I'm already 90% of the way there by building my fuel tuning box thingy anyway so why not. -Get rid of heavy battery and move it closer to the engine bay. It's currently in an annoying spot in the boot space, so going to a gel cell battery or similar and moving it closer will save a non insignificant amount on battery weight and thick cables that run the length of the car currently. (ha) -Rear seats? I can only name 2 or 3 occasions on which anyone has ever sat in the back seats of this car. The seats, belts, and rear parcel tray arrangement are over 40kg worth of stuff. So I'd like to ditch them completely but dont want an ugly looking bare rear half of the car. For privacy reasons I want to keep the rear parcel tray so I'll remake something from maybe carbon fibre or aluminium. If the seats go too then I'll make some sort of firewall type thing and try figure out a non ugly way to cover up where the bottom half of the seats went. -Front seats Currently each front seat is over 20kg (including rails) So will get some lighter ones, maybe with fixed rails if I ditch the rear seats. -Radiator Support crossmember Currently I am using an oversized piece of a 2nd crossmember that I chopped out of another carina, so I can unbolt this to take the engine out. Since its an easy shape I'm going to 3d print a mold to make a carbon fibre replacement for this, and the bonnet stand.-Get rid of the glass and replace with Lexan This is something I'm not interested in doing. It's good weight savings but it's a ball ache because you need an authority card or whatever, I can barely deal with trying to get WOFs on this bloody thing as it is haha. -Other stuff I'll learn new things as I go, doing the above. So I might come up with some new ideas or decide to ditch some of the above. But it feels like there are some exciting new things to learn, which I'm happy about. A lot of these things only save 1kg here or 2kg there etc... But they all add up. Since my gearbox is toastedd and trackdays are starting to become significantly less affordable or accessable. I'm happy to just have the car off the road again for a while, while I geek out a bit. The only thing I can say for sure, is that fun times are ahead and I'm excited to learn some new stuff, especially regarding Arduino programming, 3d printing and some carbon fibre stuff. 29 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted March 21, 2018 Author Popular Post Share Posted March 21, 2018 I've made a great start on lightening my vehicle: Didnt need any of that stuff apparently So swapping a new box in, and I find that once more the Exedy HD clutch that I've got had started to rattle the springs loose already. Which doesnt actually cause any problems apart from interfering with the knock sensor sometimes which annoys the piss out of me. So I am fitting up an OEM clutch plate and cover plate. The OEM clutch plate has rubber bits in it, instead of springs. So they never rattle and cause knock sounds. Also my fuel computer project has slowly scope creeped into a digi dash. woops Shitloads of work left to do though. Hah. Will fiddle with the screen layout / arrangement a bit more and I think I'll have a row of LEDs right across the top for a shift light, instead of a big single light. I dont know. It's actually hard to fill the screen real estate when you dont need to have everything displayed at once. Want to make it look like it belongs. Not easy. Am also still playing around with some carbon fiber stuff but havent produced anything useful as of yet. But results so far are promising. I've got a few vaccum pumps to play with thanks to Tumeke, and I've bought a bunch of vaccum bagging materials so I'll give a few different methods a go and see what works or not. I thought making a wing mirror would be interesting but the geometry is so bloody complex. Will park that one until when/if I know what I'm doing So starting on something a bit more simple, will try make a new MAF housing / pipe out of CF. Have printed half of the mould for the bellmouth part but it will need to be made from at least 4 moulds assuming this will work at all... Using the method of 3d printing with thick outer layers, fairly open infill and then filling with plaster for weight/rigidity. Then coating the moulds with wax and just doing a wet layup. For this shape I really need to plan my cuts so I'll do a few trials with some bits of paper I think. Hopefully works well but its a learning process so not expecting stellar results straight away / wont be too dissapointed if it doesnt work out. This is the underside, from where I filled it up: Much cheaper than trying to print a more rigid mould from PLA. 16 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted July 29, 2018 Author Popular Post Share Posted July 29, 2018 After a few iterations my bellmouth turned out pretty sweet! Had heaps of trouble trying to get any of the dissolvable filament options working though, so I still havent made second part of the pipe. The next thing to do is buy an all alloy radiator so I can chop it up and have a front facing air intake, so no 90 degree bend just before the throttle. In unrelated news I found this 90 degree oil filter adapter which is an absolute bloody gem:https://www.summitracing.com/int/parts/fms-m-6880-a50/overview/make/ford My remote oil filter setup has been an absolute dick punch right from day 1 and I've always battled leaks with it. This uses same threadpitch etc as the Toyota filter so works with 3S or 4AGE or similar. Lush! This will now clear my swaybar so I can get rid of the AN lines and so on. I've been making a bit more progress on my digidash thingy, 3d printed a rear housing that accepts the factory loom plugs: And I thought about using 2 screens side by side like this but in practice all of the writing is too small and it sucks looking at just numbers instead of gauges etc. But either way I'm learning a lot about electronics so I'll keep at it. I've nearly finished writing the code for my cruise control based closed loop ignition trim computer which this all ties in with. Will be interesting to see if it works. Once I've got my mish mash of parts together I'll design a circuit board that incorporates everything and then get a company to etch it or whatever they do. I've been lazy and havent had a wof or reg on this car since summer time. I signed up to a trackday in another 2 months so I've been putting in some work to fix up some shit to get it all sorted again. Cant wait! 13 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted July 30, 2018 Author Popular Post Share Posted July 30, 2018 Oh yeah so some other developments. Grabbed a Vitz alternator, just the alternator itself is 2kg lighter so I can definitely believe a 4+ kg saving with a light bracket as well. I've looked into making some brackets but CBF factor is high when SQ Engineering is only $200 or so and all the hard work is done haha. Also as mentioned @Firetruck was kind enough to give me an electric waterpump from a BMW N52 engine which is a straight six. Typically I've been opposed to EWPs as they always say you should install them without a thermostat, and adjust the water flow from the radiator to regulate the temperature. But I dont think its right to use a waterpump as a thermostat, I think its important to continually circulate the engine coolant regardless of thermostat position. BMW has the same opinion and the setup they use is cool. The pump itself is called a Pierburg CWA200 and you can find the datasheet and a cad model etc for it from the manufacturer directly. It has 4 pins on it. 12v, Earth, a PWM input signal to control pump speed, and then a frequency output that shows pump speed. So if the pump jams or is otherwise just starting to shit the bed, you have some feedback to your ECU rather than just waiting to see that your engine is cooked before doing anything. Benefits of EWP are that when I'm nanging it at 8000rpm I dont actually need 8000rpm worth of spinning the waterpump, I can just run the pump at the optimal speed to circulate coolant effectively which might be the equivilent of say 3000rpm worht of mechanical pump speed. And at very low load cruising I can slow the pump down too, which apparently is an economy gain from reduced losses. So even if an EWP is less efficient than a direct mechanical drive. benefits by not having to be run at a 1:1 ratio with engine speed. So to keep with my plan of using a thermostat I was originally looking for how I could plumb this in so it pumps water after the factory thermostat housing. but this looked like a bit of a ball ache and I would need to keep the factory waterpump/thermostat housings which are big and heavy. So I was planning to find just a normal in>out thermostat housing, hopefully with a bypass hose integrated. I found one from a Rover engine that was perfect, but then I found that the BMW thermostat which goes with this waterpump has an adjustable temperature and the gimmick factor of this is just too damn high to say no to! The thermostat and pump is pretty bulky but it will hide down low on exhaust side so not too much of a drama It has a 12v voltage input into the thermostat, if you apply no current then the thermostats goal temperature is 105 degrees. When you apply 12v to it, it applies extra heat to the wax in the thermostat and lowers its goal temperature down to 85 degrees. Using PWM or similar, once calibrated you can pick a goal temperature within this range which is awesome. Which of course begs the question for why you would ever want to run an engine at 100+ degrees. The answer is that it's damn good for fuel economy, when you are at very low load you can run the engine hot and you lose less heat from combustion into the cylinder/head/etc I think. And fuel vaporizes better I guess. Then when engine load is high, you need the extra cooling over a lower goal temperature. I dont like that the failure mode of this, is for the thermostat to stick at 105 degrees if a wire breaks or similar - But the gimmick factor is high so I'm gonna run with it haha. I would still be hesitant if not for that I can flash some warning lights on the dash if the pump speed is not within % of what is expected at any point. I've learned enough from the dash etc that I'm confident I could make a canbus based pump/thermostat controller that would work well. Interestingly the new thermostat and EWP is approximately weight neutral with the mechanical setup. Just a lot bulkier but that's fine I've got space. Gonna be awesome! 22 Quote Link to comment Share on other sites More sharing options...
Roman Posted September 28, 2018 Author Share Posted September 28, 2018 Sooooo After about a year and half break, made it back out to a trackday. It was stunningly awesome fun! Excuse the camera angle and shitty audio etc first time using my crappy gopro type camera (reminds me why I hate these things) Something funny, for about the last... forever I've had this issue where the front left of the car dives under braking. Have double checked all of the bushes, brakes, alignment, etc... Turns out that one of the handbrake cables has been jammed so its been pulling the right rear handbrake about 1/3rd of the way on all of the time! After fixing this, hooooly shit my braking distances have shortened up sooo much! Such an awesome difference. Only issues I had on the day were a piston jamming in one of the front calipers when trying to switch pads (time for a caliper rebuilt perhaps) and at the end of the day I broke teeth off another e-throttle gear. But then I realised a while back I turned off all of my smoothing in the ECU to stop that from happening. woops! Will turn that back on and should stop any further dramas hopefully. All said and done A+++++++ will trackday again 9 Quote Link to comment Share on other sites More sharing options...
Roman Posted December 8, 2018 Author Share Posted December 8, 2018 Some last minute drag day prep... 5 3 Quote Link to comment Share on other sites More sharing options...
Roman Posted December 8, 2018 Author Share Posted December 8, 2018 Super fun day at the drags, I brought my little brother along to drive. He's much more of a sensible adult than me, with family responsibilities and so on so I thought he'd enjoy having a drag day experience. He had a blast! Driving fairly conservatively as he'd never driven the car or at the drags before. But he managed to scrub 2 seconds off his best time through the day. He said "Hey ahhh when do you change gear?" "About 8000 or so" "Oh shit I was changing at five! haha" I only got two runs in myself, as with some ahhhh more aggressive launching etc the car developed some sort of drivetrain vibration. Seems like it might have just been a piece of rubber or something off track picked up on one of the semi slicks but didnt want to take my chances. So trundled back home and put the washing back on it. Hopefully its just something simple but thankfully doesnt seem engine or gearbox related. Suspecting driveshaft or tyres, the noise changes with speed but not with load. Hopefully easy fix. There's a meeeeaaannnn set of photos from the day over at DCG Photography 9 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted December 8, 2018 Author Popular Post Share Posted December 8, 2018 Digidash is coming along slowly too. Just need to figure out what to put on the sides. Waiting on some parts so my circuit board can interface with the 12v stuff from the loom plugs like lights, indicators etc. Still might change the design around a bit but I want to look 80s obnoxious / look like it belongs in the car / still be nice and readable. Currently only receives canbus info from ECU, and has an internal bulb to make the alternator work haha. Getting there but a fair bit of work left to do. Excuse the yuck graphics, work in progress: 27 Quote Link to comment Share on other sites More sharing options...
Roman Posted January 7, 2019 Author Share Posted January 7, 2019 Good news, I got my opto board all wired in and my dash computer is reading all of the on/off signals from the standard loom. Woot! But what sucked is that I cracked my LCD screen while trying to fix an issue with power wire. Damnit. I had to order a new one which has just arrived. I'm mostly ready to test the dash buuuutttt after investigating drivetrain issue from the Drags, my driveshaft is busted! The rear UJ on the rear half, is now totally stuffed. Quite lucky that I managed to drive it home from Meremere like that, although, since it would just break the shaft off directly at the diff at least it wouldnt make the same sort of racket like when the front broke. So! Obviously I need a better plan than taking out a flogged to shit 35 year old driveshaft, and replacing it with another 35 year old flogged to shit driveshaft. As this hasnt worked out too great so far. I've had some good recommendations for where I can get a new one made, which I will follow up on. But, also, I want to test my dash in the meantime and hopefully take the car on a camping adventure this week before work starts again. Does anyone have a stockpile of driveshafts kicking around? If so please let me know! Here are some deets of what I need 3 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted January 11, 2019 Author Popular Post Share Posted January 11, 2019 Got a driveshaft sorted until I can get something made up, so went on a roady to test out the dash. Drive up to Uretiti was good! As expected I really need to put some KMs on it and get a feel for what's good or whats annoying or so on. Very quickly a few things became apparent that they are fecken annoying! Also this thread has been severely lacking MSpaint so here we are: So on the plus side, the ~250? Nit screen seemed decent enough even with backlit conditions. I've got a 1000 Nit screen here to try too if I need to burn my eyeballs out! Most of the annoyance came from values flickering. Because you might be hovering on say 89.9kph and then 90.1kph... So it will flicker between 89 and 90. Options here are either that I take a rolling average of the last XYZ amount of speed results and smooth it. Or maybe only change the speedo value if the number goes up or down by 2kph or more. With the tacho, this was annoying for similar reasons in that it can read from the ECU down to a single RPM, so its a constantly moving number which is distracting. I'm thinking that I'll filter it so it only updates the screen in 100rpm increments, so will go 2400rpm, 2500rpm, etc. Because again, does it really matter, do you really need to know that the engine is doing 2451rpm? Not really. Maybe I could make it read in 50rpm increments below 2000rpm or something like that. Also when it was bright you cant actually see any of the outline lines, only the numbers and labels. So will make more sense to move labels closer to the values. I also realised that although a monochrome sort of look is nice. I setup some cruise control displays so that one button goes Red when you've activated CC, and then goes green when CC is turned on. With the colour differentiation you could instantly tell what status the cruise control was in. So I think more colours will make things easier to read. In fairness though this is essentially a low contrast colour scheme that is probably better for night time. Using a white or yellow or whatever text and it's blazingly brigher even with the same backlight settings. I'm also starting to question the merits of having the triangulated sort of face over the screen, when you're driving and it's bright you cant see any of it. Just the values on screen. So may as well just use the extra screen real estate. Good to be making some progress anyway! I'm looking forward to designing some of the more contextually aware screen functions now that the basics are sorted. First on the menu is a secondary screen for when Cruise Control is turned on. Then I'll look at some trackday related stuff and a few diagnostic pages to make life easier. It's cool having all of the standard dash info coming into this, because I can set it so (for example) if you flash the high beams, or push the brake, or whatever, in certain conditions (like while the car is stationary without engine running) you can use those car controls to navigate through menus or switch screens or whatever. Pretty chuffed to have reached that milestone of driving it with a fairly "finished" prototype though. 31 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted February 2, 2019 Author Popular Post Share Posted February 2, 2019 Okay so I've always been a big proponent for the factory inlet manifold, as, well, it's a bloody good design and most people just get rid of it because they cant fit it, or they think its ugly. Both of which are valid reasons, but both of which do not apply to me because it fits and I dont care. However! The GC @NicT has a 3D printing company called https://www.facebook.com/volumetricNZ, and makes some nifty manifolds and trumpets, printed from some fancy pants Carbon Fibre Nylon material. So here we are: The saddest part was having to unplug about 6 sensors in order to make this work haha. So the basic gist of the setup now, is: -Modelled fuel equation, differential fuel pressure taken from fuel pressure sensor and MAP sensor -MAP sensor connected to one throttle body only -FPR connected to one throttle body only -Brake booster currently disconnected from vaccuum (This shall change because its bloody scary) -No MAF or Ethrottle or cruise control (Blargh) So first impressions are that this has increased the volume of my car by at least double It's unsociable to say the least, hahaha. You can hear exactly when the cam starts to advance and introduce overlap as it gets about twice as loud again! Which I guess makes sense as there's an accoustically open path to the exhaust manifold when overlap is present. So I've given it a quick tune up, and there are some interesting observations. (By which I mean uninteresting graphs) Firstly, having the MAP sensor connected to just one TB is an absolute shit show. Because of the individual pulses in it, the MAP signal under steady conditions looks like this: Since this is something that happens once every 720 degrees, the severity of the pulses diminishes with RPM, and also goes away as the throttle opens (which makes sense as this reduces the amplitude of the pulses when there's less vaccum) So on this graph the bigger the bulge is up and down, the worse the problem is... Can see it's mostly stable by say 30% throttle Then if we look at an RPM plot we can see we're needing to go to around 5000rpm+ in order to get a stable MAP signal. It was quite funny, my Closed Loop Lambda wasnt working because it has a TPS delta threshold, it would only start working above around 6000rpm. So if wanting to do a TPS / MAP blend, I guess you'd need to only use the MAP in high RPM or high load regions. What is also interesting is that people report that with ITB you dont get very good vacuum signal generally speaking, which is why MAP sensor sucks with it. When connected to 1 runner only this is very much not the case, it pulls better vaccum than my plenum does. Right down to ~20kpa! But as per above it's MAP quality that's the issue. When teeing all 4 into a vaccum cannister you average out the signal but it also ends up a lot lower I guess. Also, I've had to forgo my lovely smooth looking MAF based fuel map, and go back to an Alpha N abomination which I guess you could just say is typically ugly for that load axis. Still very much a work in progress, but you can see pretty clearly how with ITB above a certain throttle position you're almost getting a full amount of air already. In this case the kink happens somewhere around 40% throttle, so I'll add some more resolution to that area so I can smooth the curve a bit nicer. Another unexpected thing is that it looks like max torque is now around 5500rpm, previously 6500ish with the plenum. People talk about ITB being for high rpm power but this looks like either it makes good midrange :OR: it's a mass flow restriction at higher rpm and power tapers off at that point. Still cant draw any conclusions on that one until I've refined the map a bit. One thing that's clear from looking at the logs though is that the cam timing wants to change. I see dips in the fuel logs which correspond to high amounts of intake cam advance. The standard plenum loves having right up to 50 deg cam timing it looks like this is going to want 35-40 max. All of the places with the high overlap/advance and it starts losing power. I think this is why there's the dip after 5500rpm onwards, too much cam timing everywhere. Not sure why yet. But I'll do a full sweep of cam angles and see what it shows. Maybe draw a graph? Who knows. According to Virtual Dyno, at current point in time it's making somewhere in the region of 180hp ATW at 8100rpm and max torque at 5300rpm. Which seems about right . Will see how it pans out with some cam timing optimization, looks like there's still something left in it yet. The overwhelmingly standout thing about this though is just the absolute bloody racket it makes. haha! It drives surprisingly nice at part throttle, but if I'm going to keep ITB I'll need to figure out an E-throttle solution. Cant go back from having cruise control then losing it. TL;DR: Added some things and make a bloody racket. Engine bay still looks like shit. Car still draws graphs. 18 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted February 7, 2019 Author Popular Post Share Posted February 7, 2019 I still havent had much time to play with the tune more, but got it tidied up a bit. Basically it still just falls on its face at around 5500rpm. After refining the existing map a bit more though I am less convinced that cam timing is going to help that hugely. After its peak at 5500rpm it loses about 11% cylinder fill by 7500rpm, which is an uncharacteristically aggressive drop in torque. I'm getting more convinced the throttles themselves are a mass flow restriction, and this is why torque drops after this point. But it could be something else too. Possibly the stupid inlet/outlet shape on the blacktop throttles causing turbulence or something. So thought I'd head to the internetz and see if there are similar trends on other beams ITB setups using blacktop throttles. This is the first result I find... 180hp ATW with the peak torque at 5500rpm falling on its face after that. And comparatively garbage below 4000rpm too. Almost exactly how my setup has responded! I'd describe as "small to medium length" trumpets fitted on this one: Second result that I looked up looked almost identical to the above... Hmmm. Around about same length trumpets too. Found another link which didnt have RPM scale on the dyno, only KPH as was rolling road so cant tell what RPM things are happening at. But it looked to have initially results similar to the above. But then they put on longer and longer trumpets made more power everywhere. Ended up with a 17kw gain using 110mm trumpets after starting with 35mm. So I think I'll try print some trumpets as long as will fit. Will add a curve if need be. Another thing which is quite different to the plenum setup. On a stinking hot day with the air being drawn from right at the back of the hot engine bay it lost considerably more power to heat soak. Like, Virtual Dyno and fuel map says 25-30hp kind of loss. Really flat power from then onwards yuck. I'm not sure if that can be completely accounted for just from reduced air density, but somethings making it lose a lot of power when very hot! Is this all dissapointing so far? No way, all the indicators are there that there are good results to be found with some further testing. I know the engine has the cams etc capable of making max torque up to at least 6500rpm - There's likely just one variable holding it back currently. It might be the throttle ID, it might be the trumpet shape, it might be the overall intake tract length, or lack of airbox, or something else. All of these things I will be able to test and prove/disprove one by one. What a time to be alive / have a 3D printer 15 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted February 12, 2019 Author Popular Post Share Posted February 12, 2019 Soooooo for a while now I've had an obsession with getting a "proper" bellmouth geometry on something. I successfully made a big one for the big single throttle but I really need a different radiator arrangement to make it work so its been on the back burner. But the geometry to give completely straight flow is massively massive compared to what is usually used, so its a problem when you have 4x throttles close together. With the space that is available, you have to trim down the sides of each trumpet by this much to fit 4 alongside each other. (Obviously dont need to trim front or rear but lazy modelling) So it looks like you lose most of the useful area of the bell... And looks like it would be prone to "stealing" air and maybe fuel from adjacent cylinders? Not so good. Probably better just having a smaller radius on each. Either way, I printed out a full sized bellmouth (without trimmed sides) so I can size it up in the engine bay. As it turns out that thanks to having a brake booster I've got zero room for a trumpet this big anyway on the rear and hitting the bonnet on the front will be a problem too. I've seen those cool kits where people have all of those parts you can clip together to help build an exhaust manifold. So I thought I'd try the same thing here but for an intake. So printed some parts so I can try some combos for a single runner. Base piece, a bell, 3 x straight 20mm sections and 3 x 10 degree sections. Also pictured is the bellmouth provided with the ITB kit, for an indication on how rediculous the bigger one is haha. Unlike those fancy exhaust kits though mine doesnt actually clip together because aint nobody got time for that. Also, turns out printing the straight ones was a waste of time as there's not even enough room for just the bends. Neither front or rear really fits. pooz. So I'm reprinting the bend parts with 15 degrees per segment and a bit tighter radius to see how much that helps. Based on what looks like will fit though, tipping the trumpets slightly towards the front of the engine bay is actually pretty cool because it allows more useful bellmouth area per runner. A lot more! Most of the air comes from around the sides rather than straight ahead so will be interesting to see how this goes. The question is, is the efficiency gain of the big bell worth the efficiency loss from the bend. And is the bend worth the extra runner length gained. And does any of this make a difference when you're trying to wheeze through a 45mm throttle. And the biggest question of all, will I actually finish making any of this? Some preliminary nerding seems to look like the bellmouth partially shrouding the entrance shouldnt be an issue so long as there's a bit of gap. The colour scale on this, red is 101.3kpa and green is 101.0kpa so pretty minimal loss hopefully EDIT: Just found what the factory BMW S14 engine runners look like, makes me feel like I might be on the right track. Even if the big bellmouth isnt necessary, perhaps there is a real life benefit to having them staggered to allow more clear air around each runner than you can get with straight pipes that are butted up to each other. 23 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted March 4, 2019 Author Popular Post Share Posted March 4, 2019 Some more sharns without finishing anything. Possibly some repeats sorry. But here's a pic of the Altezza touring cars that did really well in NZ many moons ago: Notice the ITBs fitted to factory runners. Or I guess you could say, factory plenum fitted to ITBs. These had class limited 10:1 compression, no VVTI (Banned?), big cams, and ITBs welded/mounted into the factory plenum. They made around 250hp with this config. Not sure if it was just class mandated that they had to stick to the original plenum/intake, or if there were other reasons for this setup. I managed to track down one of the guys that helped make these and he had some yarns to share: Quote Fitting throttle bodies in the runners helps the top end flow while the plenum from Toyota keeps the pulse tuning right to keep the torque curve as full as possible for as long as possible. We have seen a few copies of the Toyota plenums used but they destroy themselves as often they aren't built strong enough to handle all the pressure pulses coming up the runners and back down again. The toyota cast plenum is quite rigid and thickwalled. Quote I believe Lynn found the Toyota plenums worked really well for pulse tuning with Toyota already sorting volumes etc. Quote Lots of plenum testing was done before committing to putting the ITB's into the runners. We went through this with him not long ago for a rally 3sge we built last year Quote The rally motor we built last year is looking at around 250-270HP with jenvey itbs and a biggish plenum. It will depend where we set the cams on the dyno and how peaky we want the usable rev range set. Cams are the key along with porting to suit the designed hp and application Interesting that use of the standard plenum wasnt just because it was mandated. Although maybe that's why the factory throttle body is still in place. Race car rules can be weird haha. 13 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted June 27, 2019 Author Popular Post Share Posted June 27, 2019 A few different yarns here, start with the gearbox. 12 or 13 years ago, I bought, attempted to repair, a virtually brand new Altezza gearbox. It was pulled out of a car under warranty when supposedly it had only done 30(!) kilometers. Or something to that effect. The only catch - reverse didnt work, and I could never get it working. So after a bunch of frustration and dissapointment, I sold it on. Roll on to a few weeks ago where I'm moaning about how most 6 speed boxes are high kms junk now, and I remember back to this gearbox. I track down the gent I sold it to, he's still got it... it's just been in dry storage all this time, and I can buy it back! awesome. So I've stripped it all down, no faults found but I've got the service manual and more patience so I can check every single thing for the right amount of clearance, play, etc. The difference is that now I've got a full service manual with instructions for reassembly, and a lot more patience that's come with age. So I'm confident I'll get it working. Even if it takes a few attempts and part swaps to isolate the issue, it'll be worth it for sake of having essentially brand new synchros and bearings, and awesome gear shifts. It's also going to get some treats in the form of a Silvia 6th gear, and I might fix the "fourth gear circlip issue" as pictured below: What happens is imagine that the gear in the background, when the helical gears get loaded up with lots of torque, it pushes the thrust washer onto the side of that smaller gear in front of it - Which is only resting up against the outer half of the teeth on that gear. So give it enough torque, and the teeth break off that front gear and it blows itself to high hell. So some people weld that clip in place, or cut the groove deeper and make a new one, or, whatever. Apparently fixing this more than doubles the torque holding capacity of the gearbox. So I might do something about it while it's apart, maybe. Also, I bought another low km gearbox that he's had sitting in storage for 10+ years too. So that'll go back into the car in the meantime while I fix up this one. End of gearbox yarn. (for now) 13 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted June 27, 2019 Author Popular Post Share Posted June 27, 2019 Next thing - My redtop engine has finally started to make an engine rattle that I cant diagnose without taking the head off - and I cant take the head off without taking the cambelt off. I cant take the camblet off, because I've ugga dugga'd the front pulley onto the crank because I stripped the threads on it doing something stupid. So this is all a big enough clusterfuck to warrant switching over to the dual vvti engine that I've had sitting in the corner for a while. Putting this in has a few advantages, that I think I've already blathered on about. It's lighter, more powerful, tidier, and less complicated. win. Redtop engine had sentimental value as it's taken a hammering for a long time but it's earned its retirement! Rather than just doing a basic engine swap and getting the car running with minimal effort, (pfffttt) I've scope creeped this into oblivion by deciding to push the engine back as far as I can in the bay and will remake new engine mounts, gearbox mount, exhaust, driveshaft to suit. This has a bunch of benefits, mostly to do with weight savings: -I can ditch my gigantic heavy swaybar for a normal one, so no big loop around front of the engine. -Oil filter will finally fit properly! This has annoyed me for at least a decade. -Switch to alloy Altezza mounts which save a fair few kg over the utterly shit spec factory 1S mounts. -Switch to a pedal box so I've got space for the intake scheming, and get some better brake balance at trackdays. -Tip the engine slightly to one side, so intake is lower and exhaust is higher. so both fit better. -Engine as far back as is practical without cutting firewall etc. -Less engine rocking with some much better mounts, so clearances can be a little tighter. (Better road clearance to exhaust) -considering using a FWD sump with the motor tipped slightly (say 10-15deg) as this would allow the motor to sit a little lower, and the front part of the pan is much further back. -I could now make a strut brace that's dead flat across the top rather than having to bend up over the engine. -Much better alternator location, and a few kg lighter with the SQ engineering kit to use the Vitz alternator. I'm copying Truenotch by using the Landrover mount rubbers, and for now I've 3d printed some upstands while I fiddle with the engine position to see what I can get away with. Hopefully this weekend get some metal mounts made up, and since I live in the Waikato now (morrinsville) hopefully find someone local-ish who can weld the steel ones in place for me. (Should really learn this for myself one day...) Then work on the gearbox crossmember, then I can finalize dimensions for the driveshaft so I can go get a brand new one made up without having to worry about shitty old UJs breaking. The basics of the car will be largely the same, but just pretty much fixing up shitty things I did 10+ years ago when I had much less patience. 14 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted June 27, 2019 Author Popular Post Share Posted June 27, 2019 Ramble #3: Since forever, I've always had this exhaust manifold on which is a copy of the HKS 4-2-1. Altezza manifolds sit super bloody low when swapped into different cars, so fitting the likes of the beautiful TRD pipes is problematic. With the HKS pipes, the 4-2 section finishes right down by the firewall, which meant I (by which I mean someone competent, Denham) could cut the 2-1 pipes and reangle them to suit. I've always wanted to see how a 4-1 manifold would respond in comparison but I've always thought there's no chance of making them fit, and it would be difficult to modify. But since I'm currently redoing the engine mounts, I could tip the engine over to suit fitting factory Altezza options, and then I'd have more things to play with. So had a look around and I found a shitty looking second hand FGK 4-1 manifold. The FGK site says that over the factory manifold, dyno back to back swap to standard. It gains 7hp and more torque at a lower rpm. When I went and picked it up, I chortled at how bloody tiny it is! It's only 7kg and has really neat cast flanges which dont have any material where it doenst need to be. Ideal. The HKS 4-2-1 vs the FGK 4-1: The 4-1 isnt even as long as the 4-2 section on the HKS one haha. So I can have a nice transitioning bend to the under the car part, rather than my 2-1 section which has been chopped and angled about 10 degrees maybe, right by the flange. probably not ideal. The weight difference is massive though! I'm going to design my mounts etc so that I can fit both. So I can do some comparative nerding and see whats best. I'm thinking that perhaps with exhaust side VVTI now, some of the downsides of a 4-1 design (narrow high powerband) can be mitigated a little by moving the cam around. It will be interesting to see if any improvements to the powerband from the exhaust, happens because of better cylinder clearing of exhaust gas, or other mechanisms... If it's better clearing residual gas, and allowing more fresh air in, then I'll be able to quantify the differences in powerband from each simply by looking at which gives higher airflow numbers at full throttle, via the MAF sensor. I've never had any changes to the exhaust side while I've had this ECU so it'll be interesting to look at what changes. (or not) 19 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted August 13, 2019 Author Popular Post Share Posted August 13, 2019 Slow progress, because winter time insanity. Made a prototype for a new gearbox crossmember/mount arrangement. That uses much stiffer bushes and ends up with waayyyyy more ground clearance than the big standard mount. Also, if I got it cast from aluminium the entire assembly is lighter than just the rubber bush part from the standard setup. win. Not sure how to make the final version yet, but it's good to have the gearbox sitting in the right place. And have a decent set of accurate dimensions for making a proper one. Hopefully soon figure out my driveshaft and exhaust situation. I'm on the lookout for a standard 2-1 part of an Altezza exhaust if anyone's got one kicking around? 12 Quote Link to comment Share on other sites More sharing options...
Popular Post Roman Posted January 14, 2020 Author Popular Post Share Posted January 14, 2020 Aahhhhhhhhh eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa the sounds of stress of feeling like making no progress / too many things going on at once and being overwhelmed. I'm trying to put some effort into making the engine bay and wiring look tidy this time around. Its an extra layer of effort that makes things feel a lot harder. Like, there are 20 ways to do something functionally that works. Previously I'd take the path of most convenience and call it a day. But then trying to make it look good - It feels like you need to explore 10 of the options that look like shit to find 1 option that looks okay. Then you find an option that looks good but then it's impractical for working on, and you know you're gonna hate it later. Gotta find that balance. Anyway, after much deliberation I settled on a brand of lithium battery to get. Bought an EarthX unit for a few different reasons. It has a 2 year warranty where as others were only 6 months. Gives me a bit more confidence that they themselves are confident in the product. It also has a built in battery management thingy which will protect it from over/under voltage, short circuiting and a few other safety things. Since it's going back in the engine bay and I'm trying to make things look nice I've been scheming a battery box for it. So it's got a battery switch, a 100 amp fuse to run the alternator and general power circuit. Then was thinking about having a few fuses and relays in there for high current items that are close to the front of the car, like the radiator fan. But not sure on that one yet. Including battery, should be somewhere around 3kg when finished. Thinking a thin PETG printed box, so its non conductive. With an outer layer of CF for strength/heat protection/peace of mind. To go with this, trying to push all of my relays and fans to a single center mounted box. So bought one of the big sized bussmann boxes like so. Hoping to have it somewhere easy to access in the cabin, without looking obnoxious. Center console area is seeming like best choice at the minute. But it will be nice to tidy up random half empty fuse boxes and relays around the place. I bought a few kilometers of TXL wire in different gauges and colours so I've been making a new engine and body loom from scratch. It's a bit of work, but considerably easier than last time. Having all of the right tools and crimp terminals etc makes life a whole lot easier. I have learned heaps from my first time making a loom from scratch, some things I'd do differently next time for sure. I'd imagine it's considerably easier making an engine for a person that isnt obsessed with having sensors on every friggen thing. But it's been fun. Hopefully it all works without any major issues. The only problem I've had is with the Bosch e-throttle, the pins are so small and you only get 6 terminals to crimp, no spares... I overcrimped some so it pinched the wire off. So think I'll buy one with a pigtail loom and splice it on, as I'm not confident I'll be able to get 6 out of 6 on next try either if I just buy another unterminated plug. The fuel lines are easy to tidy up. As it's easy to reroute them to hide under other stuff. I wasnt happy with how heavy and yuck looking the existing fuel filter bracket is/was, which is a 2 piece metal crapola from an SW20 like so: Look at all of those wasteful 10s of grams of ugly metal bracket! Disgusting. So some internet research came up with this fella, which has a light bracket spot welded directly to the filter. God damn look at that minimalist efficiency. Scales say previously 497 grams vs 255 grams. That means another 1/4 kg of pies that I can eat. Excellent. I also impulse purchased a plenum and shaved down engine cover, because, reasons. The plenum is likely not much use on an NA setup but it was going for a steal and looked awesome. Made by Mike at MSPEC who is a maximum GC does some amazing work. To be honest I dont think I'll use any of it, apart from testing to see how it goes. But genuinely decently made parts for a beams engine are hard to come by, outside of exhaust manifolds and ITB adapters. So, hoarder reasons basically. Might sell it on after I've had a play around with it. No doubt there will be someone with a turbo setup who could give it a good home at some point. Also got Bosch e-throttle which is a nice unit. and Spartan 3 wideband with the LSU-ADV sensor. Looking forward to seeing how much difference the fast response sensor makes. Hopefully doesnt blow up either like 4.8s do. I think that sums up my "cant draw graphs with car because it doesnt go" existential crisis for now. Thanks for reading 23 Quote Link to comment Share on other sites More sharing options...
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