Please Explain :)

[noise]

yo,

OK so when I got my GTT in from Japan I found it was misfiring at high revs. I did some research and decided to get new plugs and gap them to 0.8. This basically fixed all the misfiring.

The problem is that today I went and put the boost up to 12p and the misfiring came back just as bad as ever. I have had a mechanic friend look at all my coil packs and he said they look brand new, no hints of crack or problems.

He is running stock standard rb25 N/A coil packss in his 500+hp car with no misfire problems. Yet when I try to run 12p in a almost stock expect for exhaust car it was constant misfire problems at high boost.

Is it my coil packs?

Are stock r34 coil packs shit?

Are stock N/A r33 coil packs better?

Am I going to have to buy a expensive Splitfire coil pack set?

If so why?

help

cheers

[R33S2]

Have you tried new plugs?

Is the timing right?

Are you running standard intercooler?

On my car the misfire was the drive pulley keyway was loose, that took some time to figure out!

[ferni]

I've been told the R34 Ignition system is pretty crap compared to the R33.

Try gapping the plugs down to 0.5 or 0.6mm... see if it helps.

[noise]

Havnt tried new plugs as the iridiums in are only a few months old.

Pretty sure the timing is right, had a mechanic friend check that.

Yes running standard intercooler.

I will have to ask my mate to check the drive pulley keyway, what ever that is.

I might try gapping the plugs further, is that safe?

[Fly_With_Sky]

is this cutting up (misfire) a bit jerky when it happens. If so, have you considered that it may be fuel cutting since you have upped the boost...

[Sydneykid]

Sounds like the typical standard ECU rich and retard strategy (R&R). R34 ECU's are very agressive when they see outside the normal sensor inputs. Personally I wouldn't be running the standard turbo at 12psi, I did that for 3 laps at Oran Park and it got ceramic in the cat disease. Ben did the same in his R34 at Wakefield. Around 10psi would be my max and even then the ECU is pretty agreesive and jumps to R&R mapping very quickly.

cheers

[Sydneykid]

I've been told the R34 Ignition system is pretty crap compared to the R33.

Oh my, who told you that rubbish? What evidence do they have?

The R34 coil packs produce 15% higher voltage and have faster recovery times than an R33. We tested a set about 3 years ago, searching for a problem, but it sure wasn't the coil packs.

cheers:)

[Abo Bob]

And yet a large number of people with R34's have had misfiring issues after they up the boost which have been fixed by replacing the coilpacks.

It doesn't sound like R&R to me. From what I've found and heard the R34 R&R threshold is a little higher than the R33 one.

If you gap the plugs down from 1.1 to 0.8 then you are reducing the workload of the coils hence the improvement from doing this. Then you up the boost and the problem returns. It seems pretty obvious to me but I've only got one car and the rest of my knowledge comes from the internet so may not be entirely reliable.

I don't think anyone should be running 0.5 or 0.6 mm gaps in a Skyline. There is something else wrong if that helps - or you have eleventy million kw.

Standard intercooler is fine - Sydneykid has one in his Stagea.

[noise]

is this cutting up (misfire) a bit jerky when it happens. If so, have you considered that it may be fuel cutting since you have upped the boost...

<{POST_SNAPBACK}>

Hey Sydney kid thanks for the info.

So what is the max boost I can run with standard coil packs without misfiring? 10psi?

[BLKSKY]

ive got some new splitfire coil packs if anyone is interested?

will stop misfire for good and up to 10kw extra.

tonight i will check what part number they are and then post.

i know i definately have a 008 to suit R34 GTT

cheers

[BLKSKY]

yeah they are brand new SPLITFIRE SF-DIS-008 suit R34 GTT

my mate bought them for his R33 but they dont fit.

He said $850