Roman

To be honest I've gone a bit arse about face with my suspension... I spent $$$ on things like rosejointed castor arms, big brakes etc but then my springs and shocks are utter junk! Skimped on probably the most important parts which is a bit silly. The front springs are random items found in random Mazda coilovers by my neighbour, front shocks are unknown and my rear shocks are from a hilux or something. The front of the car doesnt dip - the back raises up. This was the first thing that I asked, to people who were watching it. It rides a little harshly and I'm sure it could be better while also handling better - it's on the to-do list. The front swaybar is 24mm I think, I got it made to 1 or 2mm bigger diameter than standard. Although it's length is a lot longer as it needs to go around the front of the Altezza sump. Not running a rear swaybar at all. Front springs are at a guess somewhere in the region of 6kgmm ( 335lb) and rear springs I had made to 3.5kgmm (195lb) The spring rates feel nice, a lot nicer than when the car was super stiff all around. But I think my shocks are what's letting it down at the moment, although I think 4 link angle changes will make the biggest difference out of anything right now.

Haha that was all a great read, +1 to that picture above being hilarious

SHOCKING NEWS I actually did something cool with my car apart from making it draw stupid graphs! This week's weekend started on Thursday, at Hampton. Like so: I managed a new best laptime of 1.24.0 which is a 2.7 second increase over last time. Mainly thanks to bravery on the brakes and learning the lines a bit better. It's still having trigger related problems which gives it an early rev cut which is a pain in the ass (Randomly cuts at 6000-8000rpm depending on when it decides to play up) However I've now got a proper trigger wheel to swap over to now. I also had the wideband cut out a bit, which I suspect is because it gets very hot. Possibly because of the exhaust wrap? But it seems to be a common-ish problem, and making a brass heat sink usually fixes it apparently. Kyteler was spectating and noticed that when I hit the brakes, the rear of the car lifts UP. After thinking about this, it's the same 4 link angle problem that gives me shitty traction off the line, and is fixable with revised 4 link geometry. So I need to stop procrastinating on that one, as I've known about the problem (and the fix) for a few years haha. After trackday, I drove it about 650kms around the Coromandel for Nats, and didnt have any issues either. So super happy with that! Car's now safely back at home, awaiting the next round of pulling it to bits and wondering why I pulled it to bits.

Beams Weirdo, reporting in! Yeah you'll be in for a shitter of a time with the MAF sensor mounted like that. It needs to sit in exactly the correct diameter pipe, and having it before/after a bend makes it shit the bed too. If you want to save yourself a gigantic ball ache then you're best to get a factory airbox and cut the housing pipe part out of it. Or find a pipe that's exactly the same inside diameter, and fit it to that. It's best to have a decent length of straight pipe before and after it, to minimise turbulence. On what you've got there, I would see if you can fit it as close towards the pod filter as possible, rather than close to the bend. For what it's worth I have never been able to get my motor running properly with the factory ECU, with anything apart from a factory airbox. BUT it's mostly low load/low rpm where it causes problems, high rpm it more or less comes right so could be fine. However some people have success with using aftermarket kits by HKS or whatever which have a cast housing for the MAF sensor as part of it. They come up on trademe etc every once in a while but are a bit spendy when new. Cheapest/easiest way will be finding the correct diameter of the factory inlet, and getting a PVC pipe or something the same diameter and using that.

Any type of trying to expand the gas tank from the inside is going to end in tears. (And a volleyball shaped gas tank)

Since it's a car with big HP and so obviously grunty fuel pumps etc. Does it have any fuel cooling? If the fuel rail is getting ballzillions of heat into it, and it was tuned on cold fuel it might make it run a little leaner only when the motor gets super hot perhaps? http://www.linkecu.com/support/glossary/fuel-temp-def

There's a 10c "Fuck you" tax on Petrol for Aucklanders, remember.

Been tinkering with a few new fun things. Firstly I got the accellerometer wired in. This is super senstive, and I think will be pretty handy for helping tune ignition or quantifying suspension changes etc on the track: So as an example of how this could be useful. Go on the sweeper at Hampton downs, get some average results for that corner. Fit a rear swaybar and do another 5 laps. Has the average cornering force increased or decreased? I'm not too good at judging these kinds of things by seat of the pants, so making iterative improvements in this manner works well for me. Also got a wideband knock sensor hooked up, not controlled by the ECU but just plugs into my laptop using the Mic jack, then turn on 'listen to device' and then can hear it using headphones. Works really well, can hear all sorts of weird and wonderful noises going on. This is what it sounds like when you're listening through the laptop: Annnnnddddd I've also been working on sifting through all of the junk in the datalogs to get some useful info. Since I'll be doing a shiieeettt load of driving for Nats weekend coming up I wanted to get an idea of fuel economy. So bodged some numbers together. But the useful part from here, is that I can change things around to see what improves/detracts from the economy and I've got an easy way to see the results. I just copy the formulas into the datalog sheet and it's good to go. Not quite as good as having real time results from OBD2 I guess, but at the same time what I'm looking for here are improvements to the average. So datalogging an hour or two first gives a good sample set. Next tasks coming up are making a proper alternator tensioner (Current one didnt work with Caldina alternator properly) Adding 5 or so switches to the centre console, running to ECU. (Can use these for wanky things like a pit lane speed limiter, turn fuel pump on/off, switch fuel maps, launch control, or whatever else) And wiring up a clutch switch.. It Looks as though there are the exact provisions to fit a standard Brake Light pedal switch to the clutch too. When the clutch switch is in, I can setup launch control and flat shifting. It would be cool to have flat shifting sorted before the OS Nats trackday! And have some fun with launch control next time the drags roll around

Take out the fuel drain plug and wind something in with same thread, give it a yank?

I datalogged a trip home from Hampton today - datalogging 10 ballzillion variables at 40hz makes for a big file! About 250mb for an hour's drive. However I've been looking into coming up with a fairly robust way to analyze log files for things which need complex calculations like fuel consumption. I think all of my maths works but I'll have to datalog a few more runs and see if it stands up to scrutiny. The Litres per 100km values are about on par with what I was seeing with the factory ECU on long trips, so that's a good start I guess. The following was running closed loop with 14.7 goal AFR, so it will be interesting to lean out the goal AFR and see if it actually improves the litres per 100km figure.

Is your Avatar from Interstate 76? Yeah I've heard good things about the HP Academy. I've been having a hell of a time trying to tune my engine, just nothing was making sense. So I decided to take a step back and check some physical things like spark plug condition... Found cyl 1 and 2 spark plug holes full of oil, was intermittently running on 3 or 2 cylinders. So a whole afternoon's worth of trying to fix up AFRs was for nothing... But glad to have found the problem and fixed it. Although I was having exactly the same symptoms when trying to tune my twin injector thingy, so it turns out that might be good afterall! I'll reinstall it and give it a round 2 hoon some time after nats. I also wired in an accellerometer, my laptop battery died before I could have a good play but this is AWESOMELY sensitive. I can see it being very useful for tuning and also measuring cornering etc at trackdays. So you'd start a run on a flat piece of road, datalog it. Loop back around, advance ignition a few degrees and datalog same again at same place. then overlay the two runs and compare which gave the highest accelleration rate at each rpm. Then combine the two to suit the best values. Then iteratively fine tune it from there to find the point of minimum timing that gives best accelleration. Only really works for WOT though I guess, unless you put a stopper on the throttle body to limit it's travel to 50% or something to tune some midrange bits.

Epic! Cant wait to see some trackday hoonage in this thing.

You're getting the bad luck out of the way early, to build up the resevoir of good luck we all need for Nats trackday

This is a recording of the knock sensor audio through the rev range for those that were curious: Picture unrelated but Youtube wont let you upload just a WAV file. Will need to get someone else to drive for a bit and introduce some knock at low load / rpm to get an idea of what frequency it happens at and how it sounds. One problem with using my laptop though... There's a noticable lag in the signal as it's software processed and my laptop sucks. Bugger! So I might end up going back to an electronic stand alone amplifier instead as that should result in no latency.

Yeah most are single wire because they just earth to the block. Which makes sense, but to use with headphones etc I think you need the earth coming back with the main wire. Using this one: http://www.aliexpress.com/item/GM-Knock-Sensor-Ignition-Knock-Detonation-Sensor-for-2013-Chevrolet-Malibu-12623095/1738801957.html I dont have it bolted on the motor yet, but it pretty much works like a stethescope when you put it up against things. It's Interesting to hear the injectors fire or you can hear the intake sucking through the side of the plenum and things like that. Most of those noises couldnt be heard from the side of the block where the knock sensor normally goes, which is a good thing I guess!

Hey thanks, Yes I saw those but problem is that I want to make sure my engine isnt knocking before Nats trackday and possibly Trackday this weekend too. So didnt really have time to wait for Ebay stuff. I had a scout at Zebra, but even if there were any there, knock sensors are the worst thing possible to try and get at haha. So I depinned a factory loom plug that slotted onto the pins, then epoxied the bejezus out of the whole lot. Just like a bought one... Hah. Stoked that I've got a way to check for knock now though, I can have a bit more of a play with the timing as it's been on the conservative side.

Quick question about shielded earths, Since the standard knock sensor normally has a shielded wire, but is only single wire and new knock sensor is 2 wire. I'm using a spare loom's crank angle sensor wiring instead, as that's two wires shielded. However what do I do with the shielded earth, do I just earth it to the chassis somewhere? Not sure if they need something special.

Haha! Yeah it is awesome, thanks for the suggestion. My laptop cant charge from the car so no worries there.

Ahhh so I bought a cheap GM style wideband knock sensor. However it needs a PITA plug (not included, damn you) that you can only find on a late model LS2 or something, bugger. Just going to epoxy some crimped ends in and run a remote plug end on it. However I bodge wired it up to a Mic jack into the laptop, then as suggested used Audacity to crank it up a bit and output to Headphones. Works brilliantly! It's even better than just using knock sensor > amplifier > headphones, because this way I can record the whole lot as a WAV file and compare notes with the datalogging timestamps once I've filtered the results for the knock frequency. Tapping the knock sensor with a fork outputs a really clear sounding sound of... Well, a fork. So it shouldnt be too much interpretation required to figure out when it's knocking.

Awww damn could be keen for a pre nats shakedown at Meremere as well! Details, giz ze details!

The main thing to consider, is can you get away with widening your front track. If yes, then convert to discs running over the front face of the hub, like the bluebird ones. This will make your life sooo much easier as it adds the thickness of the top hat to the amount of room you have to fit everything. And there's a wider variety of potential matches for a disc that suits, like the bluebird ones. I've got some spare facelift SW20 calipers here if you want to test fit them. Although these are the bigger brakes compared to non facelift, it might suit you better getting the earlier / smaller / more common calipers.

You can get some nice small Wilwoods though. I'm running smallest of the Nissan 4 pots and it really limits my wheel choice because of spoke clearance. Bit of a pain.

Slightly different car, but I've had a few different brake setups in the front of my car. -Factory AA63 Celica struts/discs/calipers (Vented disc + single pot) -Same struts with SW20 twin pots and a thicker disc -Same struts with Nissan 4 pots and same disc After all that, my opinion... Look at the price and availability of consumables, and how easy it will be to maintain your car as the primary factors. Going to a wilwood 4 pot or Nissan 4 pot gives you HEAPS of brakepad options, they're about half the weight of cast steel twin pots, and are a zillion times quicker and easier to change brake pads on. It also gave a much more progressive braking feel, the single pot or twin pots gave a comparitively on/off sort of feel. On paper going to something like AE86 struts or Cressida struts with factory vented discs etc seems like an easy option but it can be difficult to get consumables for. It's a struggle to get GX61 front discs anymore I think. SW20 calipers are a bit better for consumables, can get some decent pad options. But dont expect people to have things readily in stock at the drop of a hat, if you need some new pads at the 11th hour... Like you can with most of the popular 4 pot options. Depending on your wheel choice, a Wilwood or similar 4 pot is probably the best option for a variety of reasons. But expensive too. Basically you need to decide, in this order: -Which strut you are going to run (Starlet size, AE86 size, Cressida size. All have pros and cons) -Which caliper you are going to run (Pick this first, make a bracket for it and then find a disc that fits available space) -Either way, you'll need to make a caliper bracket to fit anything decent... So if it's 90% the same amount of work to fit any of the options then you might as well start with something good I reckon, that will pay dividends in the long run with pad availability / choices / etc. Pretty hard to go past Wilwood or the likes.

Thanks Glenn! Good to know, my basemap looks to be 2-3 degrees advance behind all of that. Once I've got my knock monitoring stuff I'll set it to those figures and see how it goes.

Okay cool thanks, I'm guessing that minimal ignition timing at WOT happens at 6000rpm or there abouts (looks to be peak torque) and then tapers off a bit either side of that? One thing I dont get is that ignition timing doesnt seem to advance relative to rpm by very much. For example 6000rpm doesnt have twice as much advance as 3000rpm, so it's only got half of the time to ignite etc.