Just in case some of you don't look around at all the other places relevant racing technologies develop:

http://www.yoshimura-rd.com/products.asp

http://www.muzzys.com/catalog/sportbike_exs.html

There's a Silkolene ad in the latest "Sport Rider" that's got a photo of a works Kawasaki Superbike motor with a set of 4-2-1 headers that have primaries with about 6 inches off the head, then a step up cone, 3 small balance tubes between pairs of primaries, then what looks to be the typical medium short secondary collectors. Sorry I can't find a link to a pic of it. It's sinister looking, and would make an excellent practical joke if it didn't in fact work.

Scott, who's still interested in all this header stuff just for fun........

 

I don't see how this has to deal with ITRs, maybe how the exhuasts work but those are for Bikes and they do work different.

 

I'll spell it out for you:

Here on the ITR forum there have been countless header posts over the last year that center on the specific design of headers. Some of those that I've participated in have become VERY contentious (and I've certainly done my share of work making them so).

I've taken it upon myself to look for and share information that bears on the subject. I do this in part because it's entirely possible that someday something that looks like these things will appear on an ITR on this board and someone will be making imperious claims.

And finally, an ITR has an inline 4 cylinder motor. So do typical 600-750 MC's for which these exhausts are built. Please explain how they work so differently that there is no relevance between them.

Scott, who loves his ITR but knows it's a machine not unlike any other.....

 

My question would be what is the purpose of those tubes that connect the primaries? Seems like they are paired in firing order?

Edit: Found out what the hell those things are...now to see if there is space to put 'em in a JDM 4-1...curious if they'll do anything at all.

-Geo


[Modified by geometro, 10:02 PM 9/2/2002]

 

I'd like to know too. We should all be familiar with the crossover tubes typical on V8's about the collectors - it's some kind of cross talk thing.

One of the sites has some dyno charts comparing the presumed to be typical 4-1 stock system to the trick 4-2-1 giving maybe 5 hp across the band on an approx 160hp motor. The torque curves show large low end gains (well below the useful powerband though).

Scott, who'll probably gasp and tip over if anyone ever writes a really good description of what's going on with this stuff......