85 FB

Well, obviously the 12A's aren't the only engines notorious for backfire as I've seen a video clip of an FC doing it, and I'm sure an FD can do it as well, so obviously 13B's can do it as well. What I'm curious about is, how exactly is the backfire accomplished? Perfect exhaust (no leaks), can be standing still and rev up, while driving what RPMs to be at when deacclerating, or shifting, or whatever, etc...

I'm curious about this and could never get a straight answer. Give very good details, nothing vague, please, in any experiences of being able to do this on cue. I know a few people said that they could.

blwfly

iTrader: (4)

i coould make my blue 83 backfire in comarnd i thinks its caused by a exhaust leak plus exsive fuel

both my cats had lots of holes i could get it up to high reves like say 6-7000 as its slowing down turn the key off for bout 5-10 seconds then back on ild allways get a great bang
fun for scaring other drivers or peds

mazdaverx713b

iTrader: (91)

running rich and enough unburned fuel in the exhaust to ignite.

Randokuky

yeah just run really rich, when i first got my 7 the person you had the car be4 me broke the mixture screw and it ran REALLY rich. Any time i left off the gas it sounded like i was in a shoty drive by.

85 FB

What you all didn't mention was what engine you have when doing this. 12A or 13B? Like I said, "good details". Otherwise, I'll still be lost.

samtuck

I don't have any detals, just a report of a FD that was on the highway in front of me shoting blue flames as it pulled away, mid curve, from my friend in his subie 2.5RS who was losing traction at the time.

subaru: 0
RX-7s: 1

blwfly

iTrader: (4)

myns 12a with stock exhaust

gelkingt

I dunno if my situation will help any but in my 82 rx7, when i do a quick shift at 5000 plus rpms i will get the loud bang, but when i let off the gas slowly between shifts, i get nothing so i would say a rich condition would cause this. Plus it doesnt help that my exhaust is custom to come out infront of the rear tire on the right side which makes less backfire than when it was just running no exhaust, just cat. less restriction in the exhaust system?

blwfly

iTrader: (4)

i think the exsess fuel gets a lil trapped in the cats
on my other fb with a straight tho i cant get no bangs

fcdrifter13

Lots a fuel + no cat + 5k+ RPM = cool flames.

trochoid

iTrader: (6)

Best method I have found so far is to take it up near redline, let off for a second or 2, then give it 1/2 throttle.

85 FB

Would this work on a 13B no problem? And do I keep it in the same gear when I give it 1/2 throttle?

trochoid

iTrader: (6)

If you ever watch a race with a bunch of imports with modded bodies, and can't tell which one is the rotary, look for the flames, especially in the Japanese vids.

Short answer to you question, yes, but the FI engines don't always act the same. Keep it in the same gear. I can get get pops too when I do a high rpm rev matched down shift and a blip on the throttle.

85 FB

I have an exhaust leak near the header. Would that hinder a backfire?

trochoid

iTrader: (6)

Might even help it, now go out and practice. lol

85 FB

Well it is nighttime. And warm, so the windows'll definitely be down. *L* But, no, I am heading out tomorrow, I'll give it a try then. I'll probably give it a buzz in 2nd gear. Going near redline in 3rd would net me near 60 or higher I bet. I don't pay attention that well to what speed at what gear at redline. Bad me.

LokiRx7.1

iTrader: (1)

My car runs rich as hell, and has a leak where I bolted in a pipe to replace the cats. I didnt use lock washers, so it comes loose every now and then... I still dont get any big back-firing... a little popping and crackling, but no fire *****.... I am so disappointed...

blwfly

iTrader: (4)

i never got flames but super sonic booms