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Bad Miss At Hi Rpm

yellow34gtt
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yellow34gtt Apprentice

yellow34gtt

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Posted

Hi to all,

i need some advice on a problem which by other post sounds quite common in 34's

let me first infom you what i have had done recently to my 34gtt $ 6500.00 later i have my turbo hiflowed with trust internals from GCG, 550 cc injectors, apexi power fc computer,full hks super drager exaust,front mount, dump pipe, runnin 16 psi,walbro 255 lt pump, only just put in thinking this may fix my problem.

ok here is my problem when at hi rpm say 3500 upwards and anything above 10 psi i get pap pap pap sound like a boost cut sound some times it runs good and some times it runs bad, it was tuned in brisbane and all went fine untill i return home I'm about 900 mtrs above sea level a bit colder temp as per say.

if anybody can help me with a solution or advice my mechainc says it now could be coil packs and recomends split fire items at a Cool $ 1000.00

any help would be great thanks heaps ...... :

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yellow34gtt Apprentice

yellow34gtt

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  • Author
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could be a coil pack issue.. i have the same thing happening

try dropping your spark plug gap to like 0.6mm and see if it helps

mmm good point, i will have to try that thanks...

it is set at 0.8 at the moment from 1.1

it is a pain in the butt hey...

Bass Junky Grand Master

Bass Junky

Posted
Posted

Yep.

It's coil packs.

I wouldn't go much further than 0.8mm gap though.

Don't buy the Splitfires at $1000 though.

You should be able to get them for about $600 odd from Greenline, Nengun or Kudos Motorsport (group buy specialists who I got mine through).

Souonds like you have done the right stuff with your mods.

Where's you dyno chart? We want numbers!

yellow34gtt Apprentice

yellow34gtt

Posted
  • Author
Posted
Yep.

It's coil packs.

I wouldn't go much further than 0.8mm gap though.

Don't buy the Splitfires at $1000 though.

You should be able to get them for about $600 odd from Greenline, Nengun or Kudos Motorsport (group buy specialists who I got mine through).

Souonds like you have done the right stuff with your mods.

Where's you dyno chart? We want numbers!

thanks bass junky for the info,

did you get your coil packs local with local people or did you order them from an over seas mob and then sent to you. i looked at the 3 you said and i think kudos boys are local to order from gold coast i think..

any help on the matter .. im trying to get them in AU at the best price if possible. :D

thanks heaps

insu Rising Star

insu

Posted
Posted

Gapping down the spark plugs is a cheap fix, it just makes the spark work across the plug because the path of least resistance again becomes the spark plug, rather than the block where the coilpack usually arcs out when they're not working properly. By gapping down the spark plug you're reducing the area of burn and this can be seen as an inefficent use of burning fuel. In the long run, you're much better off changing coil-packs and running the gap as close to 1.0 as you can.

Abo Bob Grand Master

Abo Bob

Posted
Posted

Those of us who have been around a while have seen this exact problem many times. I could have told you the answer to your query just from the title of your thread.

If you gap them down to 0.6 the best you will have is a temporary solution.

Get the Splitfires and be done with it. Stock GTT coils are shit. $1000 is a rip off. Should be able to find them for around $600ish.

Oh and ditch that crappy fuel pump. You are playing with fire there. I'd hate to see you lose an engine through trying to save $100 on a the fuel pump. Someone with lower power aspirations will buy it off you as I would still recommend it up to about 230rwkw.

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