Hey guys,, When I creep up to 6K RPM on first, I can hear my exhuas making a popping sound when I shift to 2nd. Sometimes 2nd to 3rd gear. It's at the upper RPM. Sounds like it's backfiring.

I have no major mods. Just SRI, and ASpec axle back.

What you guys think?

-Tomi

 

lol, mine did thart all the time i loved it made me think i was driving a race car!!!....lol, didnt realy think it was anything....didnt pay attention to it...

 

Mine does that too. It also happens when I punch and take my foot off the pedal sudenly at any RPM above 2k. I'm pretty sure it has something to do with the back pressure. (as you've heared it between shifts, as have I) Sounds pretty cool though IMHO.

 

Whew I thought I was the only one. Hell yeah it sounds cool as shit. Hitting the RPMs really quick and letting go the gas. pop pop pop.. vroom.. haha..

 

So... nothing bad right?

 

shoot! i love the popping sound (on my automatic!!) but i'm kinda disappointed that flames don't shoot out. maybe i should remove my cat lol.

 

yeah the poping sound is also the back pressure like James said. and yeah james the exhaust will pop loud at times hahaha. and i dont think its soo much the anit surge valve....the bursts of pops after letting off the gas like james described is all coming from the back....if it was the valve wouldnt the noise come form the front of the car?

in any matter sounds good and nothing to worry about in my opinion.....unless of course you DONT have an exhaust and your making them pop sounds haha

 

Our Fits has gas...

So I'm assuming its safe. Only happens when we hit high rpm and rapidly backing off the throttle.

 

All cars that have an exhaust do that, its normal. Most likely the unburnt fuel igniting in your cat. converter (or hot exhaust piping). Sounds cool too!

Probably a combination of intake, which causes the car to dump more fuel into the engine.

No idea what an anti-surge valve is.

 

So then it sounds like we're running a little rich.

I know for sure on my 90 CRX, it pops like no other. Very low deep tone exhuast. Pretty loud, but not a fart can. boy does it pop.. haha

 

my saab pops every time it does i try to look in the side or rearview mirrors to see if i see flames at night...lol ah EJ20 growl!!...so sexy

 

EJ20's sound great. I have an 02 wrx with an apexi n1. Man does she growl. I see you have a well dressed impreza or should I say a saabaru! All in all its still a subaru. Yes this popping is backfiring. My auto sport does it as well.

 

Ive got my Fit to actually backfire a few times. It'll do it when I down shift.
I think it sounds great.

 

I've got the 50mm skunk2 system on mine and I get the pops when I downshift or let off the throttle some. It's growing on me, kind of reminds me of a scaled down version of the sound of my '84 vette when I do the same.

 

Sounds like your anti-surge valve releasing pressure nothing to worry about.

 

Yeah it definitly sounds like backpressure, you would know if its backfire. My 240 had a bad case of backfire, sounded like a shotgun.

 

haha. I can get my automatic to backfire. It happens when i downshift w/ the paddles and rev-match the tranny. It got louder now that i have a midpipe. I freaking love it!

 

its the backpressure causing a violent mix of airs inside your exhaust, basically the stock pipe size is perfect for the car you are driving, you increase the size of piping, the air will exit at different speeds, causing a pop. so far ive had a 92 sierra, 05 civic, 87 crx, and the fit all popping since i upped the pipe sizes. If it was the waste fuel being combusted in a hot cat wouldnt it do it stock considering all we have changed is the piping after the cat?

and for future reference, and this comes straight from my ASE manual, backfiring consists of the combustion cycle not being completely finished when your intake valve re-opens causing the flames to shoot up your intake and out. kinda funny, i burnt a hole in my crx's filter doing this while messing with the timing XD

 

man i love the sound. thats why i changed my exhuast to the buddyclub exhuast becuase of it. other wise i would rather rock the hks super drager that i had. heh