video/ qusetion

[supracrazy12]

Well I was watchin this video an noticed that when this gtr back fires/hits the rev limiter, it shoots a massive flame out. I was wondering is he running extreimly rich or is that just some type of aftermarket rev limiter (like msd) that was installed? http://rapidshare.de/files/678592/DAN.mpeg.html

[supracrazy12]

lookin at it again it cant be a rev limiter because it happends when he gets on the gas after he shifts it sound bad ***! but can you be running that rich that the unburnt fuel acctually explodes like that?

[JonPowell]

Its fairly normal for an engine with an atmospheric BOV....the air the ECU think is entering the engine is actually escaping through the BOV...that causes a SUPER rich condition and spits raw unburnt fuel int othe flaming hot exhaust...thus...fireballs.

[krayton]

Vid is down.

ill take my 2 guess though.

1. 2 step? or is he actually bouncing off the rev limiter.

2. Soft Rev limiter. Much better then the stock which would produe flames. (cuts ign and dumps fuel, not like stock where u cut fuel )

[kouki-gymkhana]

I remember seeing that vid posted in an Australian forum. I believe he has a launch control system in the car and that's what explains the initial fireballs when he revs before the launch. As for the subsequent fireballs, Jon Powell probably has it right...

[krayton]

well if he did it off the start. thats a 2 step

2 step: a secondary rev-limiter, commonly called a 2-Step limiter (Full Throttle, Clutch In, you use both feet, 2 step, get it?). With a user defined RPM value and Cut %, you have the ability to tune your launch to suit the track conditions.

NA cars use this to go full throttle off the line and the launch controls how much hp so they dont spin. Us turbo people use it to prespool the turbo (anti-lag system). Ive read of poeple getting 15psi build up.

its hard on the turbo mostly. AEM and most standalones have this feature. pretty cool, sounds like gun shots.

[Valley]

a little bit of everything and probably a test pipe.

[Imissmyturbo]

My RB25 used to shoot flames when I would shift. It was a combination of open BOV/off timing/overboosting on the stock ecu.