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Old 11th March 2012, 05:24 PM
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Davey Davey is offline
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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.
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Old 11th March 2012, 06:20 PM
wylliezx9r wylliezx9r is offline
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Seems like their using the theory that "bullshit baffles brains"
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Old 11th March 2012, 07:20 PM
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Quote:
Originally Posted by wylliezx9r View Post
Seems like their using the theory that "bullshit baffles brains"
I reckon so. Look at their extensivelist of dealers.

D.
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Old 11th March 2012, 08:08 PM
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Quote:
Originally Posted by Davey View Post
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
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Last edited by robo : 12th March 2012 at 08:35 AM.
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Old 12th March 2012, 07:34 AM
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deezee deezee is offline
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I could waste hours debunking this nonsense. But if people want to waste their time reading this rubbish, than an actual buying a book on engine and exhaust development and learning something, let em. Just makes them look like they have an incredibly poor understanding of engineering.
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Old 12th March 2012, 08:25 AM
robo robo is offline
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What your all saying then is that its a load of bxxlocks. Oh well!

http://www.turnermotorsport.com/p-38...e-exhaust.aspx


Bob
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Last edited by robo : 12th March 2012 at 08:34 AM.
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Old 12th March 2012, 08:52 AM
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Arm chair experts will always know best......
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Old 13th March 2012, 12:38 PM
flyerncle flyerncle is offline
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Why waste large amounts of money on an exhaust to gain little amounts of power and then fit an amp and boom box that draws mega amps from the battery and lose 10 bhp !

Their add sounds good untill you add up all the factors.
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