Exhaust popping on deceeration

J

jonesy3194

Member
Hi guys,
I
was driving behind an awesome integra the otherday and its exhaust was 'popping' on deceleration or when changing gears (had a cannon so it wasnt straight through),

Is there anyway to replicate this in a lancer? I think i know the principle behind it (unburnt fuel entering the exhaust) but how would one achieve this if its not harmful to the engine? would you need to advance the timing or run straight through pipes or whatnot

Cheers Mat
 
but would that cause it to be excessively loud? This integra wasnt overly loud or anything. Also would it be better to get a glass pack exhaust or cannon?
 
usually a messed up cat will do this, as well as uneven (might be even) header pipes i believe can do the popping sound too. Backpressure has something to do with it too

EDIT: uneven header length's will more then likely cause burbling
 
jonesy3194 said:
So it wont occur with stock headers?
Click to expand...

according to my quick googling, the sound also happened when you stab at the accel pedal quickly, so that the outside air rushes in once the exhaust gas leaves, and makes the burbling. I think, that if you are able to make your intake/exhaust system a lot more free-flowing, it will make that sound

EDIT: my friend's camry does it (rad000 on here) a lot, from the looks of it he has a catback with larger piping and a straight through muffler and twin tip.
 
jonesy3194 said:
I already have a complete CAI and i dont get anything as of yet, so i might head off to the wreckers and see if i can get my hands on an old lancer exhaust system and ill take the cat and muffler off of it and give it a go?

Also would this work for the cannon, as it is a glass packed resonator
http://www.ebay.com.au/itm/2-5-STAINLES ... 1170wt_905
Click to expand...

thats an idea. you might even want to just get the cat from the wreckers. its not really legal at all, and EPA fines arent soft, but i dont think a lancer would get done for emmisions.


http://www.ehow.com/how-does_5545351_ex ... auses.html
 
Popping on deceleration is usually when the engine is running a bit rich. and you get excess fuel, at the moment it may be happening in your lancer but your cat and resonator and muffler are all suppressing it. Since your cat converter is mainly oxidizing hydrocarbons and carbon monoxide, id say is using of alot of the available oxygen in the exhaust and leaving your fuel with nothing to burn with aswell.

My guess is remove your cat (mind you that is illegal and carries a nice fine if you get caught without one) see what happens, then maybe remove your cat and muffler if you cant hear anything.
 
What if i just got an old cat from the wreckers and drilled out the internals so it looks like the stock cat but its inconspicuously not a cat?
 
My exhaust does it all the time since ive had extractors put on, i love it. All ive got is cai, throttle body upgrade and extractors with a muffler, if i let the gear pull me down from about 3/3.5k revs itll crackle.
 
jonesy3194 said:
What if i just got an old cat from the wreckers and drilled out the internals so it looks like the stock cat but its inconspicuously not a cat?
Click to expand...

a few people may or may not do this :shh:


burbling i think is got to do with the piping, Popping and banging has to do with fuel in the exhaust because fuel wouldnt burn slowly(?)
 
jonesy3194 said:
I was looking for something similar to the sound old V8's make when they decelerate, the whole popping or backfiring sound
Click to expand...

Old V8s probably didnt have a cat, coz they were old LOL.

But seriously, just unbolt your cat, and give it a rev, see what it sounds like, just jjack your car up and undo the bolt in front of the cat. Itll cost you nothing and will learn alot more about your exhaust noise rather than speculation.
 
Yeah I've got a tune which shouldnt be making the A/F ratio too rich, headers and one resonator cut out plus a straight -through magnaflow rear muffler and mine does it sometimes. A while after getting the headers I also get a catalyst under-efficiency check engine light code up. Car still runs fine though and with great fuel economy so I just ignore my warning light...one day I'll get a high flow cat and the rear O2 sensor tricked into thinking everything is alright :lol:

Actually when I was on Narellan Rd coming into an RBT I heard the cops commenting on the burbling of the exhaust, they didnt seem too worried though...
 
My lancer pops on decelartion but i have to slightly put my foot on the accelerator (a tiny bit)
My car is running aftermarket headers to the cat and a 2.5 pipe to a very small res then to the cannon.
But heads up cops/epa will get u. its a $48 testing fee and if u dont have the stock exhaust expect bout $280 if u get done.
 
without the cat there is pops on deceleration, but they are only rare, is there anyway to increase the 'pops'? would advancing the timing achieve this?
 
You must log in or register to reply here.
Back
Top