K my gtu is running 2 1/2in straight pipe straight from the header that leads to a 4in exhaust tip. I put 93 in the car and don't know why it's not flaming. It pops all the time but never any flames. Also oil pressure gauge doesn't work could it be that it's just disconnected or something else?

 

Well, higher octane fuel is actually a little more difficult to ignite & it's a pointless waste of money to use anything other than 87 in an NA car. If it doesn't backfire when you let off, who cares? That just means the dashpot is adjusted well, the anti-afterburn valve is working (if present) and the mixture isn't overly rich.

Oil pressure gauges can go bad, the wire to the sender could be broken/disconnected, or the sender could be bad. Check the FSM for testing procedures and look at the sender/wire. It's under the oil filter on the rear iron.

 

why do you need it to "flame"


Is it disconnected? because if it isn't diconnected then it is something else