loud backfire

[Snaps]

1990, previous owner installed aftermarket mufflers. When i turn the key to full and lay into it, between shifts or when i let off i get a very loud somtimes violent sounding backfire. Also usually my dipstick is a quarter of an inch popped out. Im thinking crankcase pressures? Should i be worried?

[We Gone]

Does it have headers? or an aftermarket e-prom?

[Snaps]

Might have a prom, skip shift is eliminated

[Kevin]

Probably needs a tune

[KILLSHOTS]

There's an anti-backfire feature (forgot the actual technical term) that Marc enables on his PROMs when you install headers. When I had mine installed, I sent him my PROM for an update and when I got it back and installed it, it was backfiring so hard I thought it would blow the exhaust off. I contacted Marc and he checked his records and noticed that he had forgotten to enable this feature and he took care of it right away.

Short answer: contact Marc and order a PROM with anti-backfire enabled. Good luck.