Pelican Parts Forums

Pelican Parts Forums (http://forums.pelicanparts.com/)
-   Porsche 911 Technical Forum (http://forums.pelicanparts.com/porsche-911-technical-forum/)
-   -   This is one for you mechanical engineer types (http://forums.pelicanparts.com/porsche-911-technical-forum/93846-one-you-mechanical-engineer-types.html)

scoll911 01-11-2003 09:58 AM

This is one for you mechanical engineer types
 
I'm watching racing on the speed channel and I'm curious -- what causes flaming out of the exhaust pipes

Randy Webb 01-11-2003 10:15 AM

hot, unburned fuel meeting O2 -- tuning for max power doesn't mean all the fuel gets burned.

Doug Zielke 01-11-2003 10:17 AM

Unburned fuel igniting in the (hot) exhaust pipes.
This usually happens on the overrun. Motors with large amounts of cam overlap contribute to this phenomenon.

Wayne 962 01-11-2003 10:56 AM

They have cool flame-throwers installed just for the cameras!

-Wayne

A Quiet Boom 01-11-2003 12:18 PM

Dougs got it right in the case of Gasoline powered cars, Randy would be partially correct on NitroMethane and some Methanol cars. Actually the NitroMethane is still burning as it exits the pipes.

Kevin Stewart 01-11-2003 12:50 PM

Running a msd will do this the msd's spak stays lite a bunch longer, and will happen when there is a Y pipe in the system, Kevin

Jack Olsen 01-11-2003 01:02 PM

It's most common on Turbos, but even an ordinary rev limiter will do it sometimes.

Kevin Stewart 01-11-2003 01:08 PM

Running a msd will do this the msd's spak stays lite a bunch longer, and will happen when there is a Y pipe in the system, Kevin

Milu 01-11-2003 01:27 PM

fitting a sparkplug to your tailpipe connected to the battery with a switch in the cabin also helps flaming from the exhaust;)

widebody911 01-11-2003 01:50 PM

I'm told that when I lift at the end of the straight @ Thunderhill, my car shoots about 5' of flame out of each pipe. It also shoots flames on the dyno at the end of each test, when the tech lets up.

stlrj 01-12-2003 07:25 AM

The reason it's most common on turbos is because the K-jetronic is not equiped with the fuel shut off on decel feature that motronic incorporates to prevent this from happening.

Cheers,

Joe


All times are GMT -8. The time now is 10:49 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website


DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.