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Re: 10vt header

>	The "cost" of a header has little or nothing to do with (a) the 
>actual labor it takes to make A header, or (b) the SS used in the 
>header.  Obviously, the German piece referred to has profit built in.  
>HOWEVER, there is an enormous cost [or there should be] in R&D for an 
>honest to God high-quality SS header that helps, not hurts, performance 
>on a turbo motor.  If you don't believe me, call ANY honorable race shop 
>that builds one-off SS header[s] and tell them what you want.  Most will 
>be happy to work w/ you.  After they get done w/ you, $800 will seem like 
>chump change. There is just SOOOOO much that goes into the proper design 
>of a header.  From experience I can tell you that extensive testing [R&D] 
>goes into not only what most think of as the "header", but the collector 
>is a beast all its own.  That is, where the "header" dumps all pipes [5] 
>into one [1].  You have not only backpressure to contend with, but an 
>improper design will actually cause the exhaust to revert back on itself, 
>making temperatures and all the other monsters raise their ugly head.  
>Anti-reversion work is STILL a constant process at houses that do this 
>work all the time [Hedmann, Thorley, Hooker, etc.]  One-offing, which is 
>basically what you are talking about for the I5t, is very seldom [read 
>never] done cheaply.

Which is exactly why HONDA and RENAULT had AUDI design the headers for 
there F1 turbo 10cyl. engines.  Both engine groups felt that Audi figured 
it out....  Makes you wonder if someone in ther shop without a Dyno cell, 
and some SERIOUS computing power for the Fluid dynamics programs is going 
to come up with anything that is going to work any better or even close 
to stock....

Good luck, Let me know how they work, maybe then I'll get one.....


Eric Fletcher