mx5cartalk.com

Apparently it works. I defy anyone to explain it.

tanner wrote:When push came to shove, Tanner decided to create a completely custom exhaust system to suit the unique engine. "I used pool hose to work out the basic routing, then improved on that with a header prototyping system from Icengineworks that I like to call "header Lego". It's 1-inch pieces of tube that snap together into whatever shape I need," he says.

http://www.speedcenter.tv/content/2008/10/tanners-flyin-finish.html?p=2

Less restriction and more length for the pulses from each cylinder to combine in a magical way and produce more power.

Where's Pete? He's been reading up on all this.

Some weird pulse effect to do with the length of the runners before the main join I think. I'm sure there's an engineer around somewhere who can explain it far, far better (possibly thought of it a long long time ago too )

Edit: I see Dave beat me to it by about 45minutes. See kids, that's why you don't hit the post reply button then get "distracted" by homework...

IT's to produce the extracting scavenging effect. When one cylinder fires, you want the exhaust pulse to pass the join exactly as the next cylinder is exhausting. It assists in pulling out and helping the other cylinder due to the venturi effect created due to the tuned length. Dollar per horsepower it doesn't seem that good though. It's a hard thing to research, fit and experiment with for little gains...but if your going ten tenths it does look a bit special. I think Brian Ferrabee in QLD had a similar set of extractors on his crazy NA8.

Hellmun wrote:I think Brian Ferrabee in QLD had a similar set of extractors on his crazy NA8.

He does; as does Geoff Fane. They look fantastic (especially Geoff's, 'cause his are shiny).

Reminds me of those strange people who grow their fingernails really long.