Great Exhaust article.
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Joined: Sep 2004
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From: Murphy Texas
Great Exhaust article.
There is a great article about the complete exhaust system, from headers sizes, flow rate, X and H-pipes in the most recent HotRoding Magazine. Thought this was a good article because I am researching X pipe for my 71. And by the way just FYI, I was told that an H-pipe would be a bad idea behind the crossmember because anything more than 7.5" to 8"in of a gap would actually be worse than no pipe. An X pipe is the solution, just a bit more work, and the article said it will give you a HP increase by equalizing the system. Just FYI.
P.S. A weird fact about air and its actual mass from the article. 1 100ft square cube of air would have the weight of 38 tons! Whoa...
P.S. A weird fact about air and its actual mass from the article. 1 100ft square cube of air would have the weight of 38 tons! Whoa...
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Joined: Jul 1999
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From: Huntersville NC
Originally Posted by jake1
P.S. A weird fact about air and its actual mass from the article. 1 100ft square cube of air would have the weight of 38 tons! Whoa...
but then i put on my thinking cap... which makes me real smart, and I checked out some blimp stats...http://www.goodyearblimp.com/b_stars_stripes.html and I see that a 100X100X100 cube is actually about twice the volume of the goodyear blimp and the blimp isnt EMPTY, it is full of a gas that is lighter than air but still weighs something, and the blimp has a gw of more than 6 tons... so 38 tons is not unreasonable!!
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From: Foxfield CO 1970 Convertible
I'm following the suggestions in that article also. The way I read it, it said that an H-pipe was about as good as an X-pipe and placement wasn't very important.
My big concern is that to get a system configured correctly, you need resonators just after the collectors. This would place them right under your legs or maybe the seats. (I would like to avoid side pipes due to the noise). Has anyone done this? Has anyone seen resonators that are just big, hollow chambers without anything in them?
Bottom line - it was an excellent article and puts away a bunch of myths regarding exhaust systems.
My big concern is that to get a system configured correctly, you need resonators just after the collectors. This would place them right under your legs or maybe the seats. (I would like to avoid side pipes due to the noise). Has anyone done this? Has anyone seen resonators that are just big, hollow chambers without anything in them?
Bottom line - it was an excellent article and puts away a bunch of myths regarding exhaust systems.
C6 the C5 of tomorrow
Joined: Nov 2000
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From: Twin Cities Minnesota
Is that the article by David Vizard in Popular Hot Rodding?
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
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From: Foxfield CO 1970 Convertible
Originally Posted by 427V8
Is that the article by David Vizard in Popular Hot Rodding?
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
I do like the picture of the Vette exhaust that was put together for a 700hp NA small block. I wonder where that resonator came from???
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Joined: Dec 1999
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From: Sierra Foothills CA
Originally Posted by 427V8
Is that the article by David Vizard in Popular Hot Rodding?
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
If it is it's an old article and there are things in it that are misleading and or contradictory. I have his book where all the information comes from. And it's good.
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm
C6 the C5 of tomorrow
Joined: Nov 2000
Posts: 6,665
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From: Twin Cities Minnesota
I see what you are saying and I suppose it does make sense.
One thing I do know is that when I went from very unequal length headers to equal length headers it became very easy to tune my carb. Before the idle screws made no difference, now they are nice and sensitive.
Ed of Headers by Ed makes this point. He also is a big proponent of equal length primaries, at least within 1/2". The reason for this it that then all clyinders are getting the same mixture at the same RPM. With unequal length headers some clyinders are lean, some are rich, making it hard to tune and while it doesn't effect the power much it matters when you start running Nitrous. That lean clyinder is the first to go boom.
As far as measuring primary length, comon it's not that hard
One thing I do know is that when I went from very unequal length headers to equal length headers it became very easy to tune my carb. Before the idle screws made no difference, now they are nice and sensitive.
Ed of Headers by Ed makes this point. He also is a big proponent of equal length primaries, at least within 1/2". The reason for this it that then all clyinders are getting the same mixture at the same RPM. With unequal length headers some clyinders are lean, some are rich, making it hard to tune and while it doesn't effect the power much it matters when you start running Nitrous. That lean clyinder is the first to go boom.
As far as measuring primary length, comon it's not that hard
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For what this study is worth:
http://www.mustangexhaust.com/tech/HvsX/HvsX.htm
Seems the point here is where you want the gain,low end or high end.Interesting about "average" results,however.
http://www.mustangexhaust.com/tech/HvsX/HvsX.htm
Seems the point here is where you want the gain,low end or high end.Interesting about "average" results,however.
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From: Scottsdale Arizona
Originally Posted by 427V8
He says that the exhaust design contributes 100 times more to the intake cycle than the intake manifold design, but then goes on to say that primary tube equal lengthness in un important.
Hmmmm