91interceptorZ

iTrader: (3)

hey guys, I'm having an annoying exhaust problem with a 'popping' sound during accerleration at 1700-1900 or so and also on deceleration when close back to idle. I don't think it's a tuning issue, i've tried different combinations and still always there. I'm running short tube headers into 2 1/2" pipes and then Y's (where the cats used to be) into a 3 1/2" pipe. All the pipes are mandrel bent and go into a 3 1/2" center in center out hooker aerochamber muffler out through a single tip.

Are my pipe design too big or what the heck?? any ideas.

Thanks in advance.

Fyrstorm

iTrader: (1)

Any white smoke out the back? I once had a car that had a cracked cyl. head and water collected in the muffler and made a popping sound. I'm not saying thats what you have but maybe there's some water in the muffler sloshing around when you accellerate and slow down - and cover the input-output pipes for a second.

KNBlazer

check your timing... any SES light ?

91interceptorZ

iTrader: (3)

No water in pipes, pretty new motor, no SES light, no codes, timing correct, I actually run stock timing numbers, slight advance built into chip. Sounds like a glass pack exhaust pop almost, very annoying. When I ran it with stock chip it did it, but car ran rich, so I thought unburnt fuel in pipes lighting off, but have tuned car, and still does it. It almost like it wants to resonate (like most camaros humm about 1700-2100 rpm steady cruise), but I get no resonance, just popping.

iroc stangs

i could be totaly wrong but check the muffler. metal baffles can come off and stay in the muffler and make that popping. i had this problem in my muffler and at idle it wouldnt be to bad not very noticable but when you rev at around 2k it was a really annoying pop. try hitting agaist your muffler to see if anything is jumping around in there. good luck.

a/fool

I've seen exhaust leaks do that.

Frenchfroy

I recently bought an '84 z28 and had a buddy swap out the stock 305 for a 350. I noticed later my car had problems staying on at a steady rpm or choking out at some points of acceleration, giving off a raw gas stench. I've been told it used to be fuel injected and now it has a carburetor and there's a loud pop sometimes during deceleration. Can anyone help on what this problem might be? Or where I could start to solve this problem?

dek1285

iTrader: (3)

Hope this aint to old of a thread to respond to but i wanted to find out if the op ever figured out the source of the problem. I am having an issue and sounds almost exactly like what was stated. thanks

91interceptorZ

iTrader: (3)

now this is a really old thread. but no. ..I never did figure out the issue. I removed the exhaust up to the headers, changed the tune, but still there...I'm thinking it's something still with the tune or in the head port shape itself...perhaps even the cam. car runs very strong and no driveabliity issues, just that noise

ASE doc

I just heard a brand new Mustang with aftermarket exhaust do this same popping thing. I call it exhaust report. I really want figure out what causes it. I plan on going to dual 3" in preparation for a larger motor and I don't want to end up with that issue. I've thought maybe it's valve train or unburned fuel hitting the exhaust and firing. Maybe air reaching the exhaust valve through a leak or too short pipe. When I heard a brand new stock engine do it, it really puzzled me.