feelthesweetbea

I just went to look at a '90 rx-7 gxl with a rebuilt engine and gutted cats, it ran damn nice but it backfired when i let off the gas after hitting the redline. Is that normal??

xxxbadassfoxxxx

it could have an exhaust leak, mine did that when i had an exhaust leak, but im not sure, it could hav to do with the cats but i dunno

NOS FC3S

iTrader: (1)

No big deal. Its normal for that to happen with modded or leaking exhaust.

I kinda like it

dr0x

You probably threw a flame or two out the tail pipes.

Gutted cats + redline + sudden relief of load = flames

Drifter101

Maybe you lucked out and hes got a testpipe on it.... i wudnt complain tho, my friends dads truck shot 4 foot flames out of the back when you let off the gas, good ole sierra classics lol

KNONFS

iTrader: (14)

Normal without cats and redline in a rotary engine

den

my cats still on and i backfire, dunno about flames though. only started to happen when new bov was fitted ?!

Aaron Cake

iTrader: (1)

That is because the BOV is venting to the atmosphere, resulting in a momentarily rich condition. Puts lots of fuel into the exhaust, and then "bang".

Swift_7

That's exactly what gutting the cats were intended to do.

Ryde _Or_Die

Ya, you got some flames more than likely. I got some 6 footers the other day

Swift_7

Fu*kin Shweet Man!!! Gotta love the flames!

crazyjim

with any engine haha, I used to have an old '80 f-150 that I beat to hell offroad... jumped it and broke the exhaust, so I cut it in front of the cat... open pipes, sounded badaaaaaass lol

but yea, it'd shoot flames when I came off the redline.