The conclusion is we were both correct.:tup:

I'd say your guess is right. Most (if not all) hydrocarbons burn with a bluish-whiteish flame when in normal to lean conditions and burn yellowish-orangeish when rich.

if you were to straight pipe a stock 370z, it will spit flames because its super rich from the factory(heck if you listen for it, you can hear some popping on deceleration on a stock 370z sometimes but there are no flames because the exhaust has a cat, resonator, and muffler)

exhaust flames(aka backfire) comes from unburnt fuel passing through the exhaust and igniting inside the exhaust from the extreme heat


EDIT:
Just read through the entire thread, so it seems lean and rich will cause backfire, i never thought a lean condition would cause backfire
I learned something new today :)

People do that to me all the time, and i hear what sounds like a noise that would be made if flame was spitting out. Almost rally style

like i wanna believe mine does but i'm pretty sure i'm on a good enough tune where i should not be running lean or rich enough to cause it but who knows.

Why did you open this thread?? Now I "NEED" my car to do that gosh :yum:

worst case go get this lol

Hot Licks Exhaust: Dual Exhaust Kit

https://fbcdn-sphotos-f-a.akamaihd.n...04814127_o.jpg

My car... sorry for the chitty quality. Reduce timing and/or add fuel and this is what you end up with :)

This is during a tuning session.

long time since last post but my car does na with fast intentions LTH and catback exhaust, stillen gen 3 intakes and ported manifold and tb, with uprev tune.