hashman626

I recently got the corksport power series exhaust cat-back for my 91 coupe na. including apex power intake those are the only mods on my car. The backfiring only occurs at a certain time, when the clutch is engaged at the redline (8k) and when i press back on to the gas after moving up to the next gear following a red line and i continue to floor the gas. I don't think it is because I have the clutch and gas pressed down at the same time and I don't think it is because i come back onto the gas too early after the gear change. My exhaust before the corksport was a stock dual exhaust and the backfiring never occured when redlining

point-blank

iTrader: (9)

Raw fuel is getting into your exhaust pipe then burning off, shooting a fireball out of the tail pipe.
It is normal on rotaries with open exhaust

RotaryEvolution

iTrader: (30)

"after burn" is the technical term. after a high RPM pull raw fuel is dumped into the exhaust, you can figure out the rest.

j9fd3s

iTrader: (3)

+1 for karak.

"backfire" is one of those terms like "turning over" that's almost totally meaningless. i have never turned over a car, although i have crashed a couple.

technically a "backfire" is when the engine can fire back in to the intake. its kind of an old timey thing, from back when you had to change the timing (usually on the steering wheel) to start it (picture a hand crank). in that case backfires are bad, cause it takes your arm off.

most "backfiring" is probably gone by the mid 1920's, unless you have a porsche.

i did actually get my PP to spit fire out of the intake, but this required timing that was at least 1 tooth retarded

"afterburn" i guess would technically be fuel that is burned AFTER leaving the engine. the rotary has no exhaust valves, and there is a small amount of unburned gas that is pushed out of the port after every cycle, so they are a little notorious for this. if you're lucky that noise you're hearing is fire coming out of the tailpipe....

RotaryRocket88

iTrader: (7)

I can see this catching on. "Yeah, my rotary is equipped with an afterburner STOCK!"

arghx

iTrader: (3)

There is an anti afterburn valve in the ACV as well as a dashpot for the throttle to stop the afterburn. Honestly it's an old rotary, I wouldn't worry about it.

lunardeathgod

Cool I learned something new. I always thought it was called a backfire.

SpeedOfLife

iTrader: (16)

thirded, fourthed, whatever on 'afterburn'.

3vil

iTrader: (4)

as long as your bumper isn't melting it shouldn't be an issue

hashman626

well i was surprised it was happening because i have a cat and it's not high flow, just 170$ or so priced model from schucks

SilHaro

iTrader: (2)

You should be proud.

oakback

Do it at night (rev it up in neutral then let off quickly) and have someone watch, it's impressive.

Black Knight RX7 FC3S

iTrader: (7)

reminds me of my brothers 240 bumper burning while I was driving on the highway. Damn thing shot flames as I lifted and burnt the entire driver side rear. Was doing body work in that section too....there was also paint thinner in the hatch near the fire...glad the fire truck came quick :P