2G backfiring at full boost

[swnkylaxplyr]

I've got a 98 GSX with an Evo3, intake, 3"catback, and Greddy RS. I think the previous owner removed the boost control restrictor solenoid because I can boost up to 18 psi. Most of the times I do however, the car will seriously backfire at about 18 psi/6k rpms. I'll be accelerating fine and then the car just bucks. He never upgraded the fuel pump or injectors, so I was considering fuel cut. Also, I had to rethread the blowoff valve screw so maybe it could be leaking? I have new plugs in it, but haven't replaced the original wires yet.

 

[Dsmx17]

You answered your own question. sounds like fuel cut.

 

[swnkylaxplyr]

Okay thanks. Just wanted to get confirmation from someone who knows more than me

 

[1fst2g]

I have new plugs in it, but haven't replaced the original wires yet.

meh, I doubt it's fuel cut...I'm going to go with your wires on this one - replace those and see what happens.

 

[viperlp01]

evo 3 at 18psi.. Im almost positive your car is reaching fuel cut... at about 6k your flowing some air... I bet you it pulls like a raped ape before it hits the cut though ... If you simply do a rewire on the fuel pump your might beable to get rid of the cut... But you should consider turning the boost down somehow..

 

[swnkylaxplyr]

Thanks for the input guys I'll give it a shot. Also, I was told that the proper gap for the plugs was .44 - aren't they supposed to be gapped at .28? Thats a pretty big gap difference - could that be giving me problems? I know thats not necessarily the cause of this specific problem, but is that a big enough difference to be bad?

 

[airmail96]

As far as I know they are suppose to be gapped to .28.

 

[Hubbell91Tsi]

gap the plugs around .28-.30 and get some 7es plugs