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why?

My Splitfire coils are less than a year old and I have had two die on me. Same thing, would mis like crazy when on full boost and up in the revs. put two stockers in and it runs perfect. easiest way to check is just put in stock ones, process of elimination!

My Splitfire coils are less than a year old and I have had two die on me. Same thing, would mis like crazy when on full boost and up in the revs. put two stockers in and it runs perfect. easiest way to check is just put in stock ones, process of elimination!

No I was asking why gap the plugs down? It's a stupid idea that people have got into their heads that it is MANDATORY to buy 0.8mm gapped plugs. Nonsense!. If you only have mild mods up to 250rwkw then you start at 1.1mm and work your way down slowly. If you need to run 0.6mm gap then there is something else wrong. I have cars running 400+ kw with more than 0.8mm gap and no issues.

I have had people come to me before with missfires, frig around with the coil packs, checking fuel pressure, replacing filters, plugs, other coil packs for hours and hours and find out the CAS has been wound forward. Causes the same issue.

Set your base timing first, then do the other checks.

The tuner says of there is something wrong with the CAS, during the tuning it would already pick it up. It should cause the timing to go all over the place during the tuning process. But since it did not happen he eliminates the problem CAS first.

what do you call high boost, could still be blowing out! even with splittfires I have to run a .6 gap to run any higher than 17 psi

Well that clearly shows you have a problem elsewhere… You know that ye?

I was 24psi, 350rwkw, stock RB25 coils - 15 years old. They were very good condition obviously - 0.8mm no problems.

I wouldn’t call 24psi "high" when I know of many over 30psi using either stockers or splitfires and not having to run a filthy 0.6mm gap.

So if on near new coils you're having to go down to 0.6mm you have other issues to look at.

Could be ignitor (depending on series), the loom, connections, plugs any anything else inbetween

So in saying that

No I was asking why gap the plugs down? It's a stupid idea that people have got into their heads that it is MANDATORY to buy 0.8mm gapped plugs. Nonsense!. If you only have mild mods up to 250rwkw then you start at 1.1mm and work your way down slowly. If you need to run 0.6mm gap then there is something else wrong. I have cars running 400+ kw with more than 0.8mm gap and no issues.

Here here. 400rwkw & 0.8mm = no problems in the world with SERIOUS boost, not some small mans 17psi :D

For less than 20psi you should have a very nice gap margin on PULP

Well that clearly shows you have a problem elsewhere… You know that ye?

I was 24psi, 350rwkw, stock RB25 coils - 15 years old. They were very good condition obviously - 0.8mm no problems.

I wouldn’t call 24psi "high" when I know of many over 30psi using either stockers or splitfires and not having to run a filthy 0.6mm gap.

So if on near new coils you're having to go down to 0.6mm you have other issues to look at.

Could be ignitor (depending on series), the loom, connections, plugs any anything else inbetween

So in saying that

Here here. 400rwkw & 0.8mm = no problems in the world with SERIOUS boost, not some small mans 17psi :D

For less than 20psi you should have a very nice gap margin on PULP

thanks nismoid you could be onto something, maybe it's my bad tuneing, maybe its not, since my car now runs 380 rwkw at 24 psi useing the same coils and same plugs! maybe it's more common a problem than you think!

That result honestly means nothing, unless of course you still need a gap of 0.6 to achieve it... in which case you still have a problem.

So indeed it is a common problem, a common problem in that people think 0.6 is acceptable (that is the problem).

Its hiding the fact there is something else in the setup letting the overall down.

fair enough, I was only offering an idea to try, I could possibly run a higher gap but i'm too lazy to try, it idles smooth, gets good economy, goes like stink and doesn't miss a beat, I have put on a larger turbo and havn't tried larger gap yet, maybe the inlet temps play a big part?

So indeed it is a common problem, a common problem in that people think 0.6 is acceptable (that is the problem).

Its hiding the fact there is something else in the setup letting the overall down.

I think I love you.

Probably not it, but ill ask anyway, what boost controller you running?

I had a similar issue on the dyno, car started sounding like it was missfiring anything over 18psi and couldnt work out why. Then i remembered that the Profec was set to a max boost cut of 18psi, anything over and it sounded like it was missfiring, turned it off and she was all sweet.

So it is 100% missfiring and not just sounding like it is?

Edited by PM-R33
mr benno is first in line i believe...

Yes, he broke the news to me tonight.....didn't even tell me to my face, bloody phone call.

He told me you are actually alright in person, I thought you were a flamin mongrel all these years :down:

Spark plugs an shit (just to keep it on topic)

Splitfires are shit these days, mine have done exactly the same, swapped them out for stockers and my intermittant miss magically disappeared. Although stockers still arnt good enough for higher boost so it's onto plan C...

Didn't the HKS Drag GTR use stockers?

No I was asking why gap the plugs down? It's a stupid idea that people have got into their heads that it is MANDATORY to buy 0.8mm gapped plugs. Nonsense!. If you only have mild mods up to 250rwkw then you start at 1.1mm and work your way down slowly. If you need to run 0.6mm gap then there is something else wrong. I have cars running 400+ kw with more than 0.8mm gap and no issues.

I have had people come to me before with missfires, frig around with the coil packs, checking fuel pressure, replacing filters, plugs, other coil packs for hours and hours and find out the CAS has been wound forward. Causes the same issue.

Set your base timing first, then do the other checks.

quick question in regards to base timing ...

my base timing is set to 17 degrees (R34 GTT) and I'm pretty sure that's not the factory base timing ... we only found out AFTER the ecu was remapped. The tuner said to leave it, it shouldn't be an issue ... but I have occasional misfires.

Could this be due to the base timing being set to 17 deg? I was told by the tuner if we change the base timing now, the remap tune would be useless and we'd have to do it again.

It all depends on how much timing correction he has put in on the tune.

Going back 2 degrees is not going to make a hell of a lot of difference to the power - although it can make 10hp difference in most cases. But where the timing is set too high, it can mean the difference between life and death for your engine. It's not a matter of whether 15 or 17 is right, it's a matter of it being correct everywhere.

I can't tell you whether your tune has been done correctly because 17 deg base timing is not exactly a bad thing, but check it out all the same, it may be causing your problem, it may not.

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