i put shorty headers on my 91 305 camaro(its a TBI motor). it was running ok before, fairly smooth, but now that i have the headers on its running rough, backfiring when i downshift and let the engine slow me down, I adjusted the timing alittle but it didnt seem to help a whole lot. I dont have a muffler on yet and i dont have the smog pump hooked to the converter yet-soon though. Its got new plugs, new wires, cap and rotor. If anyone has some advice I’d appreciate it. thanks
intake, carb, cam, take all emissions shit off, good muffler, vaccum advance hei. and your set!
newb… why did you pick shortys and i dont want to sound like a dick and dont build a 305…
Without that smog pump you may be confusing the o2 sensor and upsetting the a/f. I can’t remember if that system is closed loop on the o2, haven’t dealt with one in a while.
Put it back together so it is all the same as it was when it ran right (except the headers) and go from there. The headers in and of themselves should not cause drivability issues.
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backfiring when i downshift and let the engine slow me down,
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Does it run ok when your not downshifting it? If you have no muffler, sometimes it is normal to hear a snap or pop when downshifting and letting it rev down. Especially if a car does not have have a convertor or muffler.
i got the converter on but it still pops way too much for it to be normal. it didnt pop last year when the old exhaust rotted off and all i had was a converter. i think one of the headers has a small leak and is sucking air or something and causing it to pop, but its just a guess.