Still Get A Missfire With Splitfires

[WogsRus]

Ok so some time ago i took my car to teh tuners, it turned out my splitfire coils were NG, so i had them replaced under warranty and so forth.

New set in, has been for about 2 moths, and i still have some issues. I am running 14 psi and the car will have a slight pop/misfire, literaly like 1 cylinder only, at about 4500 rpm, when under hard throtle in second gear.

I am runing a .75 gap, as i am trying to have the bigest gap for the best complete burn.

I am running the car as per my sig. I am hesitant to try a different gap as i think with splitfires they really should finer a bigger gap no poroblems.

I also tried a PFC with the car on a base map at 14 psi and the car seamed a LOT better with the issue, is it possible that the ecu might be cousing it.

ALSO

with a PFC, can what are the optimal setting for the coil dwell and charge time?

[WogsRus]

dam it i knew it was a hard question but come on.

[made_guy]

your boost is too high for the stock turbo.

[R31Nismoid]

1. Too much boost on the stock turbo which is just sending around hot air.

2. Your still persisting with that silly remap ECU - get rid of it

3. You probably have some bad wiring somewhere, which isnt helping

[Evil34]

Hey mate,

I had the same problem and it turned out to be that my car wasnt tuned properly. I put the splitfires in and regapped the plugs and then i had my boost controller and car tuned on the dyno and now i have no issues.

Did you put the split fires in before or after you had the missfire? If not you need to do the plugs and gap them to somewhere between .75 and .8

Also what type of plugs are you running? I had to change my plugs from Iridiums to platinums and am getting much better spark.

My car now makes 184rwkw on .75 bar as the tuner found that anymore boost than that with the factory computer the car was loosing power due to the stock computer dumping fuel and timing.

Hope this give you a little help.

[jeffworld2]

if it runs fine with a stock ecu or power fc base map, then it may be misfiring because of fuel not spark. check your dyno printout to see if its leaning out.

i dont trust your ecu. what sort of "pop" does it make, can you feel it or just hear it?

[lighty01]

Yeah, too much boost on the stock turbo which is just sending around hot air.

Sorry to hijack,

but wouldnt having a good FMIC cool down the air?

[jeffworld2]

basically when its that hot you cant fit it through the turbo, so it wont get to the front mount

1 bar is probably fine airflow wie, but you may lose your turbine wheel

Edited October 23, 2007 by jeffworld2

[STATUS]

piss off the central 20 ecu.

[IDO 11S R32]

The boost level you are running is fine, my car had a similar problem, take it to a good tuner and they will sort it out for you. It could be a number of things. With my car it was found that the coils were stuffed, they were replaced, still not 100%, then they checked the fuel pressure and found it was dropping under load, this was a simple fix as it was just the pump not earthing properly, ran a new earth wire, then fixed a couple of air leakes and the car ran perfectly! Your car may have different issues but you should take it to someone who knows GTR's like Hills Motorsport or CRD, they are abit pricey but they know what they are doing, if you take it to someone who is not familier with the car then you are just paying them to experiment on it! And it will probably cost you more in the long run. I know this from experience, I once took a car I owned to a tuner who was cheap, but because he was unsure of what he was doing he ended up spending more time on the car and ended up costing more then the well know guy who quoted me more but was more of a specialist on that particular car. So do it right the 1st time.

[PHaT MR30]

yeh another R33 owner I know made 229rwkw on 15psi with std turbo, turbo back, front mount, Mine ECU and splitfires.

That was a one off dyno run, however only runs 12psi normally.

Wogs are you sure your ECU doesn't have a boost cut and its spiking in second gear? I don't know much about those Gizzmo things though.

Where are you getting power to the coils from?

I agree with ash though, bin the ECU and get a PFC and give summers a call

[R31Nismoid]

Sorry IDO 11S R32 - but 14psi is not safe at all. Saying so is quite incorrect.

[WogsRus]

dam from no replies to 10.

1) The stock turbo of mine is indestructable, the dam thing won't let go. LOL. it has seen 16 psi for about 30 minuts almost constant and nothing. LOL. But the FMIC and the Inlet sheilding and CAI takes care of keeping the air inlet temps low. So i am preatty sure that is OK.

2) Yeah i keep persisiting with teh Central 20, as PFC cost are high, but thanks to Blake i have one but now need to do everything else before i tune it.

3) ECU definatly has no R&R or boost cut all unlikited and so forth.

4) Gizzm EBC rock, spikes are 1 psi as the wastegate has been oversized.

5) Power and so forth to the coils is stock is there anythign to check there, earth appears to be good.

6) The pop is a funny one, it's like what happens when the coils break down. I do my own tunig with the laptop and the AFR appear to be OK, the pop is still there if i add extra fuel and so forht. I also have a aftermarket fuel pressure regulator and the stock in line, so fuel pressure seams ok.

Other thing to note is that the dam AFM is maxing out at 6300 rpm in high geras . LOL.

[WogsRus]

14 psi is fine if your trying to BLOW it up. LOL>

[The Mafia]

pops are probably detonation......

14psi+ out of a stock turbo is absolutley stupid, the wheel will go to dust and its simply right out of its efficiency range. They aren't designed to go that high on boost, as they just turn into a blowdryer. Too much hot air.

Do you want to kill your engine?

[WogsRus]

mate my inlet temps are well below 50 deg C, intercooler runs water sprays to activate above 60 deg C. Detonation would keep on hapening, this is a pop and then nothing. Detonation normally aoocurs continualy.

In regards to engine it hasn't done it any harm yet, been like that for 1 year. AFR are safe and detonation was never there when on the dyno ect.

[WogsRus]

BUT i will check it out, thanks Mafia, my computer stuffed up.