Exhaust pops on down rev.
09-30-2005, 03:36 PM
#1
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Exhaust pops on down rev.
Afer getting my cutout I have noticed that my exhaust pops a ton when you bring it above 4k and let it down rev you get a few pops which are pretty loud. One of my friends said it was because it was dumping fuel on the downrev. Could this be true?
09-30-2005, 04:39 PM
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Re: Exhaust pops on down rev.
Originally Posted by lookingforwheels
My car does the same thing, sometimes everytime I shift it will pop or backfire, I think it has something to do with the backpressure.
09-30-2005, 04:42 PM
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Re: Exhaust pops on down rev.
Originally Posted by Jazsun
Really? So would getting new headers/ypipe/high flow cat, get rid off the popping?
09-30-2005, 04:45 PM
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Re: Exhaust pops on down rev.
Originally Posted by Jazsun
Really? So would getting new headers/ypipe/high flow cat, get rid off the popping?
I think it pops and backfires like that because of low backpressure.
09-30-2005, 06:48 PM
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Re: Exhaust pops on down rev.
I could totally have my head up my a**, but I think the computer on these cars takes it to zero fuel on decell, which obviously creates a lean condition. My carburated cars never did this.
I thought I read somewhere that having a tune, like from madz28 would fix it, because he will fix the zero fuel biz.
I thought I read somewhere that having a tune, like from madz28 would fix it, because he will fix the zero fuel biz.
09-30-2005, 07:36 PM
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Re: Exhaust pops on down rev.
Originally Posted by birdman1
I could totally have my head up my a**, but I think the computer on these cars takes it to zero fuel on decell, which obviously creates a lean condition. My carburated cars never did this.
I thought I read somewhere that having a tune, like from madz28 would fix it, because he will fix the zero fuel biz.
I thought I read somewhere that having a tune, like from madz28 would fix it, because he will fix the zero fuel biz.
09-30-2005, 07:37 PM
#12
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Re: Exhaust pops on down rev.
Originally Posted by Future_Z_Owner
Noone likes the sound? I think its cool.
09-30-2005, 07:37 PM
#13
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Re: Exhaust pops on down rev.
my flowmaster 40 does this. i drove another camaro with a flowmaster 40 and it did the same thing. I think it just doesnt have enough backpressure so it creates a bubble like pocket in the exhaust then it "pops" when it exits. But yet that's just my thinking.
09-30-2005, 10:18 PM
#14
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Re: Exhaust pops on down rev.
I think it sounds friggin sick 
My idea of why it pops is this:
When the car is up in the rpms, its dumping loads of fuel/air and exhausting that same amount... well when you suddenly decellerate, it isn't pushing as much exhaust out, so it creates a sort of vacuum... well something must fill that void, so either exhaust gases or ambient air fill it and the pops result from the vacuum being filled suddenly.
Like when you turn a soda bottle full of water upside down, it must go chug chug chug so the air can fill the space between each releasing of water. Notice that when you turn the bottle on it's side so that water flows out smoothly it doesn't chug like before... this would simulate keeping a steady, low, rpm.
or something
My idea of why it pops is this:
When the car is up in the rpms, its dumping loads of fuel/air and exhausting that same amount... well when you suddenly decellerate, it isn't pushing as much exhaust out, so it creates a sort of vacuum... well something must fill that void, so either exhaust gases or ambient air fill it and the pops result from the vacuum being filled suddenly.
Like when you turn a soda bottle full of water upside down, it must go chug chug chug so the air can fill the space between each releasing of water. Notice that when you turn the bottle on it's side so that water flows out smoothly it doesn't chug like before... this would simulate keeping a steady, low, rpm.
or something
