Hey guys I have a first gen. this ? is for a buddy of mine who has a second gen and hes back firing he doesnt have a cat. and the motor has about 17,000 miles on it. does anybody know what is making the car back fire ? (Im sure you do) thanks guys

 

You answered it...

 

the purpose of a cat is to burn off any unburnt fuel that remains in the exhaust. Without it, the unburt fuel vapor doesnt burn off clean like it should with a cat, but in the form of a nice fireball

 

here's your answer.. it's an RX-7

 

Backfires rule!

 

yea when i was running mine down the highway with open headers....it backfired a lot...now with everything back on....it just pops

but when it backfires....it shoots 2 little fireballs

 

Afterburn, as is the proper term for the effect you are noticing, is common on "unplugged" '7s and even some with high flow cats, although the quality with a cat is not as nice since the cat is actively combating it as much as possible. I know. I had cats. Had, because as soon as I take my baby back on the road, after emissions testing, they are coming off.

However, if its grossly excessive you may be running too rich.

 

I miss my old exhaust

 

Mine backfires with stock everything at high RPM shifting.

Slo7, you ran open HEADER on the HIGHWAY?!

 

hadauken!

 

My car backfired WITH a bonez high flow cat, now I have no cat (just a test pipe)

 

indeed i did...my ears are still ringing haha