http://www.gt40s.com/ubbthreads/showflat.p...o=&fpart=1&vc=1



sorta kinda applicable

moi!



this one is applicable



http://www.gt40s.com/ubbthreads/showflat.p...e//fpart/1/vc/1

What were you doing in a GT40 forum?



Mark

um it was a link from the miata forum

I suppose that's ok then.



Mark

Oooh man. Talk about irony.



I don't know about Formula None, but the NASCAR guys realized long ago that for headers that have to fit in an actual chassis, it's kind of pointless, since any bend in the tube will affect how pressure pulses travel and are reflected. They don't seem to care about things many people think are important, like equal length runners. As long as the tubes clear the chassis, and have as few bends as possible, that's all that seems to matter.



And then I see things like equal length shorty V8 headers that look like a knot of earthworms. The NASCAR guys seem to be right, since they rarely make any significant difference over a similar unequal length header.

Yeah, F1 just has very short headers with no resistance/backpressure at all so there's very little point in trying to tune them, but knowing F1 I'd imagine they still spend wads of money on it.



Mark

he drives an mx6!

i read somewhere that one of the teams (i wanna say ferrari) has one guy who builds all the headers, out of iconel, they take 50man hours EACH and are replaced every race (season before last they had a couple failures during the race).



they are a little "weird" BIG diameter primary tubes, and smallish collectors.



on one of his posts that adam fellow mentions tuning the exhaust doesnt matter until you're turning over 10,000 rpms

I think the reason the collectors are small is to cut down on the air disruption caused by bigger holes in the bodywork.



I'm not sure about exhaust tuning being worthless below 10k rpm, I'd like to see his reasoning on that one.



Mark