Should I Tune With Stock Computer?

[Nothing(V)an]

I have an R33 gts-t which used to pop like crazy at 4.5rpm got irridium plugs which solved the problem. I recently got front mount and exhaust put it so naturally the car is boosting alot higher now and the popping/missfire is back. Alot of people have told me its just the timing and i should get it tuned up. The popping or missfire isnt as bad as before, it doesnt always happen or when it does if i hammer it and i keep the revs above 4.5grand within gear changes it doesnt do it either. I have been told that the stock ecu tunes itself and a tune would be pointless, is this true? Car is stock other than mods mentioned. Also could it be the fuel pump?

[mad082]

the stock ecu can't be tuned.

what heat range and gap were the plugs?

[jake33]

i have exactly the same problem as you. yeah the stock ECU cant be tuned.

however,

when boost is increased, it throws out the timing causing it to run rich. ive been told that ya can still fiddle with things, even if you got a stock ecu. im going to get my car dyno'd and the timing adjusted with to hopefully make it run a little more efficently. been told that it will eliminate pinging ect.. too (not that i have any)

Edited July 10, 2007 by jake33

[TurboX]

I seem to remember that Zoom had an article about a bleeder system that stops the FPR from seeing all the boost pressure which in turn reduces the Fuel Pressure and leans it out slightly under boost.

This may be a simple but effective option, but I would only do it on a dyno to keep track of the Air/Fuel Ratio.

Its similar to bleeding your wastegate for more boost, but in this case the opposite for less fuel pressure.

[ricsvtr]

Im not 100% sure but cant the timing be adjusted via the crank angle sensor?

[ricsvtr]

Im not 100% sure but cant the timing be adjusted via the crank angle sensor?

Sorry, double post

Edited July 10, 2007 by ricsvtr

[WRRR]

Yes you can adjust the base timing at the CAS but you are just advancing or retarding in a step form. ie if you reduce the timing to stop pinging using the CAS base timing you will just start your advance curve from a lower point and it will likely run like a dog (almost assured). The ECU runs preset maps for fuel, timing etc. based on an assumed base timing point - the one they tell you to tune to in the manual.

[JieLine]

I have the same problem. I serviced my car, and put in platinums gapped at 0.8 which made the car start popping at full throttle. I rang a few performance shops and found out that platniums suck for the car? So I brought copper ones, which stopped most of the popping. Still pops like once or twice, but yeh, ive got an SAFC Neo on the car, which is really out of tune so im hoping with that tuned, everything will be sweet...

Ive been told by my mate that it could be boost cut/fuel cut, but I still think its gotta do with my ignition, maybe my coil packs have had it

[R33silverS2]

I have an R33 gts-t which used to pop like crazy at 4.5rpm got irridium plugs which solved the problem. I recently got front mount and exhaust put it so naturally the car is boosting alot higher now and the popping/missfire is back. Alot of people have told me its just the timing and i should get it tuned up. The popping or missfire isnt as bad as before, it doesnt always happen or when it does if i hammer it and i keep the revs above 4.5grand within gear changes it doesnt do it either. I have been told that the stock ecu tunes itself and a tune would be pointless, is this true? Car is stock other than mods mentioned. Also could it be the fuel pump?

I'd take a look at your coilpacks. They probably have a fine crack in them causing the miss-fire. My car had this exact problem but i took the packs out and wrapped some duck tape around them and it went away for good. Can run 13psi fine with no miss-fire. there is plenty of info on coil pack issues, the diy section has the coil pack tapeing fix.

[Nothing(V)an]

i have irridium plugs gapped to .8 and i have checked my coils, they are fine. Its weird coz it never happens in 1st even when i redline, the higher the gear the more it pops. Im getting a boost guage installed on the weekend because my stock boost is almost getting to the +7 mark on my stock boost guage, which is alot of boost for just front mount and exhaust. Also my solenoid isnt connected to a nipple at the moment as the new kit didnt have one so its setup with some sort bypass at the moment.

[grandmasterb]

Pretty sure Dr Drift can tune RB25 ECU's now so might be worth giving him a call and discuss getting a tune???

Personally i would be getting rid of the iridiums and put in copper plugs and save your money. How long have you had the car and did the previous owner do the high boost mod with the stock solenoid???

GMB

[R33silverS2]

i have irridium plugs gapped to .8 and i have checked my coils, they are fine. Its weird coz it never happens in 1st even when i redline, the higher the gear the more it pops. Im getting a boost guage installed on the weekend because my stock boost is almost getting to the +7 mark on my stock boost guage, which is alot of boost for just front mount and exhaust. Also my solenoid isnt connected to a nipple at the moment as the new kit didnt have one so its setup with some sort bypass at the moment.

Your boost is way to high for those mods, you are prob hitting rich and retard as well. You need to either weld a nipple onto the piping to connect to the standard siolenoid or get one taped in with a thread. Where is the hose running from the solenoid t piece going to? Sounds just like my car when i got exhaust and cooler done. I coiuldn't see anything wrond with my packs either but taped em up and it went away. also i had a nipple tig welded onto the piping just before the crossover pipe which droped the boost back sown to normal levels about 9 i think from memory. With no -aftermarket management 14psi or so will make your car run bad with flat spots right in the middle of the rev range.

[Dr_Drift]

GMB is correct... 33s can now be done as well

[33gtst]

Sam will be doing a remap of my RB25 as soon as it's back from the machine shop & assembled

[RBwhatever]

I hear Independant motorsports can do remaps for R33's too. They're in Victoria though.

[The Mafia]

I can see many problems in this thread.

1 - Too much boost

2 - Iridium and Platnium plugs

3 - Lack of knowledge (The "She just neesd more boost" attitude)

Answers to the problems listed above:

1 - Find out how much boost you can run safely, and what actually happens when you increase the boost. (lots of things)

2 - They are shit plugs. Go and spend $20 on copper BKR7E NGK plugs. I run them at 300rwkw, with a 0.8mm gap. Perfect. Changed whenever.

3 - Read. Find out how the skyline works. Find out what happens with the factory ECU and too much boost. Find out before you break your car.

[Dr_Drift]

R33 Remap - Example

Standard R33

FMIC

040 Fuel Pump

3" Turbo Back Exhaust

HyperGear TR43

STD AFM

STD Inj

STD Air Box

Remapped R33 ECU - 45 mins of dyno time

More to come with upgraded injector and afm

[TailsTails]

R33 Remap - Example

Standard R33

FMIC

040 Fuel Pump

3" Turbo Back Exhaust

HyperGear TR43

STD AFM

STD Inj

STD Air Box

Remapped R33 ECU - 45 mins of dyno time

More to come with upgraded injector and afm

Who can perform a remap, what's required other than a dyno for a workshop to do something like this? I've currently got a fuel controler running very lean at low RPM to achieve a similar result, but that's far from perfect.

Edited September 8, 2007 by TailsTails