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since I fitted the 3" dump pipe, when I go full throttle to the redline I get a pop/miss between about 5000rpm and 6000rpm, then it smoothes out and revs freely to the redline.

If I use half to 3/4 throttle it revs smoothly to redline without any problems.

Any idea what might be causing this and what I need to do to resolve?

since I fitted the 3" dump pipe, when I go full throttle to the redline I get a pop/miss between about 5000rpm and 6000rpm, then it smoothes out and revs freely to the redline.

If I use half to 3/4 throttle it revs smoothly to redline without any problems.

Any idea what might be causing this and what I need to do to resolve?

That would be boost cut (or excessive air flow cut as it is properly known...)

Your AFM is maxing out at those revs...

Few solutions... Lean the SAFC out at those revs... Fuel cut defender... Z32 AFM... Less boost... 0.8mm gap on the plugs may help but I doubt it in this case...

That would be boost cut (or excessive air flow cut as it is properly known...)

 

Your AFM is maxing out at those revs...

 

Few solutions...  Lean the SAFC out at those revs...  Fuel cut defender...  Z32 AFM...  Less boost...  0.8mm gap on the plugs may help but I doubt it in this case...

hmmm....OK....will have a look at the plugs first, but the previous owner reckons they are iridiums and gapped to 0.7

If that doesn't help I'll clean the AFM coz it looks pretty dirty (what about removing the mesh?....you think that would help?)

THEN I will try lowering the boost a tad, and if all else fails have the SAFC retuned on a dyno by someone who knows what they are doing.

Thanks for the info Adrian

well thats what my problem was, couple of solutions for different problems there :D

Yeah, thanks....I think I'll change the plugs to some plain old NGK coppers anyway and see if that helps.

Has anyone tried the electrical tape on the coil packs trick I read in a thread somewhere which is supposed to resolve some coil issues?

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