Clever exhaust

[robo]

Originally Posted by Davey

Only works properly when coupled with head work, new cams etc,etc,etc, look at the rest of the website, they sell it as a package. The exhaust manifold is a tiny part of the equation and probably accounts for less than 2% of the power output. Whem its that marginal primary collector lengths being equal count for at least 50% of the benefit of the extractor manifold's benefit so to not use equal length primaries is actually going to give negative results.

They can't even use proper scientific language, there is no such thing as negative pressure, pressure is simply a measurement of load acting on a surface. A total vacuum is actually zero pressure, therefore there is no such thing as -8psi (a figure they quote in their website). 0(zero) pounds per square inch is absolute vacuum, i.e. no pressure!

D.

You are right in part Honda tested some headers like these on the dyno and found 3hp with no engine mods so the gains are small. No one is going to re-invent the wheel here but the difference between a 1965 2ltr engines hp and the modern day version has been doubled and made up over many years of tiny bits like this. So if you are in the throws of knocking up some headers is it not worth pushing out the boat and grabbing that 3hp? If you were a race team you would be crazy to ignore it.

Bob