Turbo Spark plug gap

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yeyo_racing
Posts: 36
Joined: Wed Jan 18, 2006 7:11 pm
Location: Puerto Rico

Turbo Spark plug gap

Post by yeyo_racing »

What spark plug gap are you guys running for 8psi on a 2.8 turbo? My engine it's cutting off past 5k rpm and I think it's the plugs.

ECM has been chiped for 2bar map by Sinister, has MSD 6a box and MSD coil, cap and rotor and Magnecor wires. New module, new pickup, stock timing. Running 1 range colder Autolite plugs (number 23) @ .34

The engine was tuned on a dyno with BEGI FMU and Apexi but haven't been able to go past 5k ish

It feels as and ECM cut off but it isn't cuz it's kinda gradual. It's making full boost @ 3500 and keeps on going hard until it reaches 5K and starts to feel slower then around 5200 to 5300 rpms it cuts off. :bad:
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Shaun41178(2)
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Location: Ben Phelps is an alleged scammer

Re: Turbo Spark plug gap

Post by Shaun41178(2) »

That gap seems a little high. I think I was running around .025-.028 on mine. i would have to pull my plug gap gauge to know for sure though. I do know I had to come down quite a bit from stock even with my aftermarket ignition.

What does your dyno graph look like when the spark cuts out?
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL

530 whp is greater than 312
yeyo_racing
Posts: 36
Joined: Wed Jan 18, 2006 7:11 pm
Location: Puerto Rico

Re: Turbo Spark plug gap

Post by yeyo_racing »

Thanks for replying Shaun. I was really hoping for you to chime in.

You know I didn't get a dyno snapshot but it looked like this

Image
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Shaun41178(2)
Posts: 8358
Joined: Fri Nov 19, 2004 7:12 pm
Location: Ben Phelps is an alleged scammer

Re: Turbo Spark plug gap

Post by Shaun41178(2) »

Put the gap down to .025 and see what happens. If it still cuts out at 5200 then I am pretty sure I know what your problem is. I was having a similar problem when I first got my setup running. keep me updated
FieroPhrek working on that ls4 swap for 18 years and counting now. 18 years!!!!! LOL

530 whp is greater than 312
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