The Tuning Talk Thread - Forced Induction EFI & JZ Tuning.

[mr1jz]

Is the heat soak in regards to the fuel. I found that when i have run a fuel cooler on previous cars, i have much more accurate and stable AFR's

[thechuckster]

Wilbo wasn't sure what the problem but was postulating it could be the injectors. He's logging fuel pressure as part of his dynamic dead-time calcs, and it has a good FPR.

He found that after heat soaking the motor (e.g. turn off after long/hard drive, then start up shortly after) his idle AFRs had gone from slightly rich to ~17:1.

The injector duty time and fuel pressure would be the same as when cold when it was showing better (richer) AFRs - hence the theory that the Sard's had significant changes in opening-time as temps changed.

The working solution was to run the fuel map rich and use ARF-targeting to pull the fuel out while it was cold (a sort of reverse warm-up map). When he left for Brisbane, the ECU with cool motor was at -10% trim.


oh ... and his in-tank 040 pump is rather noisy (but healthy).

[mr1jz]

Does he have a surge tank because i found that this was the problem in the past. The hot unused fuel returns to the surge and the cyle continues to the point where the surge is hot to touch.. By fitting a fuel cooler on the return side, the temps dropped dramatically

[thechuckster]

stock fuel lines and tank only

[JP]

Wilbo's car was at my place for the afternoon getting the fuel system sorted. The bosch 044 pump was cavitating and aerating the fuel, a second pump was tried and it acted the same way. I modded his pump hanger to accept two walbro's, got all that fitted and working but then the stock 2J reg couldn't handle the pressure and was running 70psi base.... Turbosmart FPR800 fitted with 3/8 inlet and 5/16 outlet and the pressure is now stable with no more random pressure drops.

[ecko]

not sure if this is the best place but
1jz/2jz coil pack connectors
you need 5 housings and 10 teminals



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[nuk1ear]

wow this is awesome, i just noticed this thread. Im a bit new to tuning but its what i wanna do myself too. I do basically all mechanical work i have the tools to do on my turbo Mr2, and it has a POS microtech on it atm (MT8) and im putting on a V4+ Wolf3d soon which will be much better and allow a tonne more control over more parts of the car. Installing an XF ISCV and i have LS2 coil packs to go on along with some custom high tension leads ill whip up soon. Glad to see theres a thread for self tuning, something im very interested in about learning

[jdm93]

Great read - but one question >< .. whats one to do when they have auto ... I'm looking to self tune mine not to ofar down the track (still deciding on turbo - posted here -

I was thinking along the lines of keeping it simple with an Apexi Neo ?

my thoughts were:

with the larger turbo, bigger injectors - trick the ecu into thinking there's less load on the engine, which would make it run richer and thereby increase timing??

(newbie do excuse any silly comments ...)

I've just seen that auto Jzx have issues with the mentioned ecus in this thread ,, (something about shift points of the auto) - well only really seen an Emanage Ultimate work ok with the auto.. hrmm

[JP]

when the stock ECU see's less load, it will run leaner

[jdm93]

just did the Neo :

97 Chaser, 1jz vvti
3" mild steel exhaust with high flow cat
K&N pod intake
Walbro 342 fuel pump
AUTO

final settings I left it at were:

low end has +'s to stop any knock at full boost around peak torque and top end is trimmed: feels stronger from 5000rpm =D

1500 = +1
2000 = +2
2500 = +3
3000 = +3
3500 = +1
4000 = 0
4500 = -2
5000 = -5
5500 = -5
6000 = -5
6500 = -5
7000 = -5
7500 = -5
8000 = -5

[1JZ-Rolla]

Tuned my 1JZ quickly on the dyno yesterday after fitting a GT3582 and new 6-1 exhaust manifold to replace the previous Y-pipe & GT3076, interestingly it had quite a good resistance to knock on 98RON pump fuel, settled on 19 degrees of timing at peak torque & 20psi boost. Interestingly, it could wear an extra 4 degrees timing (23 degrees total) without any sign of knock, however low-midrange power dropped noticeably, supporting the MBT tuning theory.

Anyone else got comparitive ignition maps for a tuned 1JZ (single turbo etc)? Seems the major limiting factor on OEM twin turbo setups is the inefficiency/backpressure/high IAT holding back ignition advance?

Cheers
Phil

[loop it]

1jz mx83 made 306 rwkw on 22psi with this tune i know its heaps coarse i have another map that i propose to use but i dont have time for the dyno anytime soon so ill post it up soon too... maybe someone can give me their opinion on it
cheers

[loop it]

this is the timing for above mentioned power

[loop it]

proposed maps

[Indelible]

no offence but is there any point posting blurry or small images that no one can read any info off to help?