Roman

Yeah should be fun. It'll be a few weeks away though as there's a few bits that I need to order. Getting stuff from the UK works out pretty decently at the moment haha.

PWM controllers do exist but they are shit. As the way you get down to 20hp is by having 50hp spray for only 40% of the time. Since they can only run at 20hz or there abouts you get say 100 engine cycles running rich and 100 engine cycles running crazy lean. This is why people blow up motors. Having two seperate stages is a better way to approach the issue.

If you have nozzles at each intake runner, at some point there's a junction where it splits the main high pressure line into 4. Or splits into 2, then 2 lots of 2. At these junctions, if they're not setup with careful consideration it's possible that flow gets biased to one pipe or the other. Which causes a lean condition on one cylinder, which is exactly what you're trying to avoid by moving away from a single pre-throttle setup. Since nitrous becomes a gas almost instantaneously after coming out of the nozzle, (state change happens at something like 250psi) I dont believe there's much issue in spraying from a single nozzle pre throttle body, it will just go where the air goes. However the same does not necessarily apply to fuel, if you're also spraying fuel pre-throttle body (which I am not) Another benefit of spraying pre throttle body, is that as soon as you shut the throttle, no more nitrous. If you plumb to each runner, because nitrous acts as a replacement for the air and there's still some in the lines back towards the solenoid after throttle snaps shut. I would imagine that there's the possibility of it causing the throttle run on a bit while the last of the nitrous comes out of any lines. Which, in my opinion, is less than ideal and possibly more of a compromise than spraying from a single nozzle. Ideally I'd have 4x EGT sensors on the exhaust already and a controller for them first, diyautotune has a cool CAN controller for multiple thermocouples that I've had my eye on for a while.

Yeah I saw that, seems easy enough! Nitrous has an insane amount of cooling when it changes state from a liquid to gas. Even just giving it a quick blip on the solenoid and the nozzle freezes up and all of the lines go super cold. If I decide to spray from a single nozzle pre-throttle body, I'll likely hook up the heater lines to throttle body again to avoid having it ice open or issues with the e-throttle getting too cold(?) Might just be better to go direct port and be done with it, but I think either option when you're running a dry setup has fewer dire consequences when you dont need to worry about the fuel falling out of the air. It comes out of the nozzle at something like -80deg Fahrenheit. So cools your intake charge well below ambient temps... Which helps with detonation suppression thankfully as you've got much less margin for error getting ignition timing right.

Not sure, I suspect its expensive which is why I tried to avoid finding this out before committing to the idea haha. As it might put me off. In the longer term, if it seems like fun. It might end up more cost effective to get a BOC account and rent a large bottle and then refill the smaller one myself. Not sure whats involved with having a big bottle at home, cant see why it would be any different to argon or CO2 etc though. But if you're running a reasonably sensible shot (say 50-60hp) and have some smarts around when its activated. A 10 pound bottle can last a fairly decent amount of time.

Bahaha! Nitrous gets a bad rap because it's sold in kits which are literally just hook it up then people "Spray and pray" when you go WOT. From a generic kit where there's zero fucks given about the particular engine etc its running on. And I believe there's a tendency for people to get greedy because its so easy to just upsize the jets and hope your motor doesnt blow up. (and then it does) In most of the above situations you've got zero consistency with activation rpm, zero compensation for bottle pressure, zero control over ignition timing/knock, zero control over a leanout, etc. With ECU wizardry, in my opinion, you can cirumvent all of these issues. (Once this is finished I will have used up nearly all of my inputs and outputs) Example: -Do not activate if bottle pressure is too low -have a fuel map based on rpm and bottle pressure -switch off if lean or knocking -leave nitrous fuel map on for "safety overrun" after nitrous has stopped spraying -have a minimum activation rpm -only use in 3rd gear onwards etc. With some understanding of its operation, and running as a dry setup (so injectors provide the fuel instead of a random spray from a nozzle) I think I will be able to get some fairly precise and repeatable results. Cant say for sure, but that's the fun part. I've got a good plan in my head already but I would say 90% of my time setting this up before first operation will be setitng up smarts in the ECU rather than the physical install.

This sentence requires some amending: Alright alright, so maybe this doesnt make much sense compared to turbo or supercharger or whatever. And maybe some pessimistic people will say "Carrying both fuel and oxidizer in an old car is an idiotic idea and you're going to blow up" Well guess what? Lots of other things have carried both fuel and oxidizer on board without major issues. The Messerschmidt 163 Komet carried Hydrogen Peroxide as an oxidizer. It featured an impressively low rate of dissolving its pilots (less than 1 in 10) which was better than any other rocket powered aircraft in service at time (none, therefore it was the best) The Challenger spacecraft flew NINE successful missions with both on board, before having a minor fuel/oxidizer interaction issue on the 10th: Also lets stop and consider that the titanic didnt carry an oxidizer on board, and yet it killed way more people than both the Komet Challenger combined... And didnt even do anything cool like shoot down bombers or fly around the planet. 0% success rate! As you can see from the above evidence, Nitrous is not only highly entertaining, but also has only a very limited probability of causing your vehicle to explode. It's far from a certainty!

Selling an Innovate LC2 if anyone needs/wants one. As mentioned in thread, I swapped to another wideband controller but still blew up sensors... The actual fault was turning on the wideband before the engine has started, not the sensor or controller. So this is now surplus. $100 comes with the upgrade kit to 4.9 sensor and firmware updated. (No sensor though unless you want one of the ones I blew up...) //oldschool.co.nz/index.php?/topic/53342-fs-innovate-lc2-wideband-controller-for-bosch-49-100/#entry1724130

Someones got a steady hand alright!

Repost/spam from the photography thread, but thought this was interesting / slightly relevant to thread. Macro photo I took of the end of a 6 hole Toyota Altezza injector.

My car's wiring is a good analogy here. I have always hated doing wiring, so I outsourced a lot of the wiring to get relays, fuses, etc etc all setup to convert the car from carb to EFI many years ago. (Thanks Dad) The problem is, for a long time I didnt have a bloody clue what any of it did, or even where some of it was. It always terrified me that I'd get to a trackday, or be on a road trip a long way from home and have some issues with the wiring. And then not have the first clue on how to resolve the issue. Since then, even though I hated every minute of it, I persisted and learned more about it and now I understand where it all goes and what it all does. Unfortunately a lot of people are in this exact same situation with their EFI / tune. They ship their car away, and get back a little box full of smoke and mirrors that makes their car go. Then when their car doesnt go anymore, or they get to Taupo where the elevation affects their tune and it runs like shit. They cant do anything but shrug their shoulders. There's no need for anyone here to be one of these people, when the only barrier to understanding something is spending the time to learn about it.

Ran some tests on injector timing this afternoon. So looking for the setting that gives the richest AFR. As that means more of the fuel is actually going into the cylinder and burning properly. Surprsingly/not surprisingly looks like theres a clear trend there. Only thing I dont understand is why it wants LESS advance as RPM increases? I would have thought because RPM increases and there's less time between events, you'd want to start spraying earlier. Anyway... So looks like ~400 deg BTDC combustion (end of injection), then up to 450, then eventually down to 250 for high rpm. Disregarding the 8025rpm one will just set to 250. So looking at this graph from the Link documentation: It looks at though before 5500rpm it finishes spraying its fuel BEFORE the intake valves open. Then after 7000rpm it's mainly spraying fuel while valves are already open.

I prefer AFR to Lambda, just because that's what I'm used to. But yeah if using flex fuel then Lambda is the way to do it.

Hahahaha good lord this is going to be epic. I think I've learned that for all of the fucking around and wasting money that I've done with replacing second hand junk with more second hand junk. I could have just bought everything brand new instead and had zero headaches. Love your work pie man.

New coilpacks and plugs fitted, awesome. Old coilpacks on the left, new coilpacks on the right: The top of the coilpacks are filled with a cooling fluid (which frigging stinks if you ever cut one open) So the new design has more cooling fluid in the top by the looks, and flatter plug design which is a bit of a pain. However near the bottom of the coilpack the new one is also ribbed for my blocks pleasure, I think this is so if you have an oil leak down into a spark plug well, it holds the oil up instead of falling down around the spark plug. Good idea I guess. So new coilpacks fitted, idle seems nicer and car's running well but the bloody ticking/knocking noise is still there! With some help once more from the DIYEFI thread, found it seems to be happening on the verge of VVTI starting to engage. Then, thinking about it, the VVTI pulley is whats probably been making that rattle at idle thats been driving me nuts for god knows how long! Decided to bit the bullet and buy a brand new pulley, no point in mucking around with second hand stuff that's gonna do the same thing. I got the pulley installed, and then also found that my previous pulley was jamming at a minimum of 12 degrees advance, this new one now goes right down to zero. Which could possibly mean a little extra top end power, awesome. It's been a crazy expensive last few months though, the new tires were exciting but the rest has been on replacements or consumables or fixups, rather than fun stuff. I bought a brass bush for the gearbox shifter as well, I think the plastic one in mine is starting to wear a bit. Hopefully this might help a bit to prevent accidentally shifting out of the gate when trying to get 2nd gear (Going into the void where reverse exists!) Not too long till some Taupo trackdays, hopefully some of this effort pays off and I have some fun and reliable days at the track.

More VVTI related WTFs. Today I replaced the VVTI pulley with a brand new one. Now it follows orders perfectly and drops to zero degrees as it should. So it wasnt a problem with cam offset, and it wasnt a problem with minimum duty cycle on the solenoid. The problem was some crud stuck inside the old VVTI pulley or something like that. Soooooo this is interesting news as gaining 12 degrees more cam angle retard should help with top end power. If it makes more power, it should run a little leaner... Previously it has been +- 13:1 all the way to redline. Results: wtf! Mega lean now. Either I've just unlocked a shitload more power (skeptical) or this 12 degrees difference has now made injector timing critical at that sort of RPM range. Or maybe a bit of both. Interesting results anyway though, look forward to fixing up the fuel tomorrow and then seeing how it goes by comparison. Would be awesome to have unlocked some more doorts for trackday at that rpm.

I think I've managed to bodge it. I think the trick here though, is to never undo the pulley ever again, ever.

Does cross threading the thread in the end of your crankshaft, for the pulley, count as a form of masturbation? Because I think I just fucked myself

If you look to the right of the yellow vertical line on the time plot. When it applies 5% dc cam angle does drop to zero instead of 12 deg.

Thanks Dwlee, no I havent considered a custom PID as I've considered it beyond the scope of my abilities (especially since theres a VVTI preset already there) I think the high derivative gain is on account of that the pulley naturally tries to pull itself back to the most retarded position when the cambelt pulls on it? However, the plot thickens! Check this out: When my RPM drops below the minimum threshold that VVTI operates at, the cam angle does drop to zero. But when it comes to the VVTI operation rpm range, if I look at custom PID settings. The minimum duty cycle for the oil solenoid is currently set to 20%. Which causes... 12 degrees advance. Mind blown, have been driving the car for years like this and never bothered to check, just assumed 12 degrees was zero haha. It likely means more power up top by retarding the cam that extra 12 degrees. Will be interesting to see if my fuel map changes by much. Tomorrow I will reduce the minimum DC for the oil solenoid and see how it goes.

Oh god how have I managed to miss that cam angle offset haha. Thanks I'll get that done.

"Zero" degrees on that map is actually 12 degrees. Because I'm using the PID for VVTI control from an Altezza that has a different offset on the cam angle sensor I think (12 degrees different I'd imagine...) So it's maybe not as sharper transition as it would seem. However yes this is a good suggestion, thanks. Thinking about it, I've had a rattle at idle for frigging ages, and I've always thought it relates to valve clearances even though I've checked several times and they're all within spec. So I might have a good listen and see if it sounds like its coming from the pulley. If so I'll just replace it.

Phil is now one of those blokes, Who's quite sick of my mitsi jokes. He saw no potential, in fully sequential, As fuel isnt why his car smokes.

Went for a drive Previously my VVTI map looked like this: So I tried setting it all to zero between 2000 and 4000rpm except for full load area.... Seemed to sound the same once car had warmed up. So I went the other way, and set it all to 25 degrees including the low down areas where I'd always had zero. It looks as though this may have sorted it. Maybe the time that it clatters, is when its just coming off its base position, or is just above it. So set to stay well above it and so far so good. Will need to go for a longer drive to confirm though. Maybe this type of oil is contributing, recently started using a Penrite 5w30 when I've previously been using magnatec 5w30. I've noticed that oil pressure goes a fair bit lower at idle now, possibly running hotter oil temps or something. Sheesh I think I owe you a few beers by now Downtrail! And a few others here too. Thanks for the point in the right direction