Hi.

Whats the deal with race cars throwing flames out of their mufflers? I read somewhere that flames come out of cars that are running rich on fuel. Especialy Turbo cars and the ones equipped with mis-firing systems. So why flames? How is it that the extra gas flames-up, comming out of the muffler on these cars? Can I have this effect without the flame-thrower kit (the one Buddah got) and just by tweaking the fuel curves a bit?

 

my 1st gen crx would pop fireballs out the exhaust on down shifts or inbetween shifts when at WOT...I had the carb race prepped and it was a pretty free flowing exhaust...it ran hella rich!

and the fire is from unburn fuel in the hot exhaust thats all

 

hot exhaust is right, gas doesn't NEED spark to combust

 

dont u have to have a gutted or no cat to shoot flames out of ur exhaust?

 

you can shoot flames from an open header

my buddy's Golf shoots flames, no cat but full exahust...

we were trying to shoot flames from an open downpipe from a turbo B20 but it didn't work Guess it depends on your state of tune.

 

u guys are nuts!!!

 

Yah I used to shoot flames with my old dsm.

lol my civic backfired on a shift the other day,,, sounded like a gunshot.

 

my crx had no cat cuz it didnt need one for that year cuz it wasnt fuel injected...straight pipe to performance muffler!

 

HAHA my crx didnt have a cat either, mine was an 86 i put a 2 inch exhaust on it, that thing was fkn loud lol, so much bloddy backpressure, even without the cat that car passed emmisions so good to lol, my friend told me today he saw some dude driving my old car haha he said he was fixing it up now i gotta try and find this guy

 

the new SRT-4 will do that......

 

Your man is Buddah.

 

 

FIrst you need to be running slightly rich. Even if your car doesn't usually run rich, often when you take your foot of from wide open throttle, there was a lot of fuel being dumped and suddenly your car doesn't need it, so it exits through the exhaust creating a temporary rich condition. This is why you'll often see this happening to racecars when they shift or just before or into a corner, since they are lifting their foot off the throttle. Second, it needs heat. The heat is provided by the heat of the exhaust, and once again, a car that has a higher exhaust gas temperature will more likely cause ignition of unburnt fuel exiting the system. Often, turbo cars are the ones with flames because they not only have a lot of fuel and run a richer air/fuel ratio, but also have hotter exhaust temperatures. But still, any car can do it. Catalytics don't help because they basically slow down the time it takes for the rich fuel to exit the exhaust and give it time to vaporize of burn and particularly because the catalytic gets WAY hotter than the rest of the exhaust for emissions purposes, it tend to burn off any extra fuel leaving the exhaust before it finally gets out. Lastly, the final ingredient is oxygen. The extra fuel enrichment leaving your exhaust, even when hot, usually does not ignite until it either comes close to exiting your exhaust or actually exits your exhaust when it is exposed to oxygen (since combustion or creating flames requires oxygen as a key ingredient).
If you wanna be a goof, you can hook up a spark plug to the tip of your muffler and turn up your fuel pressure to create a fuel rich environment, but then you'd just be a goof.

 

...ok who actually read that last post hahaha

 

I did it was informative...

 

i read it

 

hey i hahve a 1986 CRX Carb(ugh, damn DX!)


what can i do to add some performance gain

I know exhasut cat boro CAI but what can i do to get the car to be a bit quicker in the motor departmen

What do you mean by race prepping

 

1986CRX - You have an EW2 motor.. CDM 12 valve head (non cvcc) responds very well to port and polish. Colt Cams in Langley BC makes great regrinds for your car. Your car does not come with a cat. CAI is unavailable to you since you have a carb. Exhaust - header - low restriction resonator, 2" piping - low restriction muffler.If you stick to the stock kehin 2bbl carb, you will get about 115-120hp. If you weber 32/36 you can get 130hp. I ditched my 32/36 as it was a total pain to tune...and that is all you will be able to make...which isn't so bad since your car weighs about 1800 lbs...

 

we light smokes off the exhaust of my friends dirt bikes when we're in the trails... no flames though