why do rotaries spit so much flames?
 

i know the rotary engines are notorious for spitting out flames. why is this so? does the air fuel mixture have anything to do with it or is it just the overlap that occurs?

they run rich

Uh yeah, just because a car runs rich doesn't mean its going to spit flames. That just means its going to smell like gas, and burn eyes.

The rotary engine, by design, is imperfect. The combustion chamber is long and narrow, HORRIBLE if you are trying to get a complete burn.

I think it is because of the very high exhaust gas temperature which makes the exhaust sytem hot enough to ignite any raw/unburnt fuel that leaves the exhaust port.

Possibly that and they are inefficent in burning all the a/f mixture.

it has to do with a number of factors. The incomplete burn on most turbo rotaries, the tuning, the temperature of the exhaust, the sometimes retarded amount of overlap, the wasted spark ignition... I think a lot of it starts with the factory engine management. The factory computers don't cut the fuel on decel from what i remember, they just run it very lean for better throttle transition. this typically causes a pooling in the exhaust pipes where the heat is generally high enough light it off. now... we all know that we need 3 parts for compbustion - ignition, fuel, and AIR - you see the flames when that cocktail reaches the air.

Ray

i remember reading that a large part of why this happens is due to oil being present in the combustion chamber to lubricate the apex seals. don't know for sure though its just something i remember reading on the forum.

what's more flammable, oil or gas?

maybe it's a combination of everything you guys have mentioned.......

maybe its magic

It has to do with just about everything that was mentioned already.

Most RXs that throw flames have a free flowing exhaust with no cats. This causes the unburnt fuel (from running rich) and noctious (sp?) gasses from combustion (that would normally get burned by the cat) to combust at the tailpipe. This happens because inside the ehaust there is no oxygen, and you can't have a flame without some oxygen present. When this coctail of unburnt gasses hits the atmoshpere outside the exhaust...bam... a flame.

ay it keeps tailgaters away and sure makes a hell of a scare when poping flames flying at 100mph past a bus stop full of ppl lol

lol +1 funny^^^^^^^

Thats so funny

Harry potter get outta my exhaust system silly goose.

Agreed.....
Cuz I spit hot fire....