Superchargers and headers???
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Joined: Oct 2001
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Superchargers and headers???
When I was rebuilding a B&M 144 blower I bought the B&M book and they said with a proper overlap cam, which is just about any stock camshaft, that headers did not make any extra horse power. With the proper overlap the incoming charge would blow out the remaining exhaust.
Is this true on the LSx? If not what kind of extra power do we see with headers on a S/C engine?
Funny story after I got the re-build kit in I called B&M with a question and they said, "Well don't you have a blower lathe for the impellers?"
I could have gone through the phone and strangled the guy. 
So instead of buying a freakin blower lather I pasted sand paper to the work bench and hand sanded the seals and test fit the rotors for three days. 
Is this true on the LSx? If not what kind of extra power do we see with headers on a S/C engine?
Funny story after I got the re-build kit in I called B&M with a question and they said, "Well don't you have a blower lathe for the impellers?"
I could have gone through the phone and strangled the guy. So instead of buying a freakin blower lather I pasted sand paper to the work bench and hand sanded the seals and test fit the rotors for three days.
Melting Slicks
Joined: Aug 2006
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From: Powell TN
Cruise-In VIII Veteran
I may get blasted for this but it is my humble opinion:
Headers only have an effect up to a point. That point being where they stop being a restriction. Since a lot more air flows out of the exhaust with FI, headers will be an improvement over the stock exhaust. If the headers you choose are big enough to carry the entire amount of airflow then they are all you need. If, later on, you up the boost to 20 psi or change to a larger head unit, then going to a larger diameter header would improve horsepower since the smaller headers may now not be able to carry the new airflow.
Bottom line is it is about volume/smoothness with FI, not tube length, collector design, etc. All that is for N/A motors. This is why Powerlabs saw no improvement on same day, before and after dyno runs when he went from 1 3/4" headers to 1 7/8".
Headers only have an effect up to a point. That point being where they stop being a restriction. Since a lot more air flows out of the exhaust with FI, headers will be an improvement over the stock exhaust. If the headers you choose are big enough to carry the entire amount of airflow then they are all you need. If, later on, you up the boost to 20 psi or change to a larger head unit, then going to a larger diameter header would improve horsepower since the smaller headers may now not be able to carry the new airflow.
Bottom line is it is about volume/smoothness with FI, not tube length, collector design, etc. All that is for N/A motors. This is why Powerlabs saw no improvement on same day, before and after dyno runs when he went from 1 3/4" headers to 1 7/8".
Last edited by 'VETTE PHASE; Feb 1, 2011 at 08:52 PM.
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From: Central Jersey
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You dont need to run headers at all with a supercharger kit. It depends on what power you are looking for. We do pleanty of blowers on stock exhaust cars. Headers will add between 30-40 rwhp in most cases. It depends on if that extra HP is worth the money for the addition of the headers.
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Joined: Oct 2001
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You dont need to run headers at all with a supercharger kit. It depends on what power you are looking for. We do pleanty of blowers on stock exhaust cars. Headers will add between 30-40 rwhp in most cases. It depends on if that extra HP is worth the money for the addition of the headers.
Safety Car
Joined: Nov 2007
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From: Bethesda MD
Are you seeing the same gains on PD as for the centris? I seem to recall seeing that for whatever reason the lower pressure centris (e.g. 5-6lb of boost) respond well to headers while the lower pressure Maggies don't seem to gain much.
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B&M and Maggies are the same, a dedicated intake manifold for the blower, maybe the stock manifold is restrictive to boost and that is why headers help with external mounted blowers?
Race Director
Joined: Jan 2006
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I understand that headers will increase the volumetric efficiency of any engine, and will actually lower the running pressure of a forced induction engine. So, if your supercharger is pullied to produce 5 psi, the same combo using headers may make the equivilent of only 3.5 to 4 psi. So, slap a set of headers on your engine, use a smaller pulley to restore the original psi, and enjoy the additional power, while not stressing the engine any more than you originally intended to do.
Good luck.
Good luck.
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Brett Foote
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From: Amityville ny 631-608-1986
I understand that headers will increase the volumetric efficiency of any engine, and will actually lower the running pressure of a forced induction engine. So, if your supercharger is pullied to produce 5 psi, the same combo using headers may make the equivilent of only 3.5 to 4 psi. So, slap a set of headers on your engine, use a smaller pulley to restore the original psi, and enjoy the additional power, while not stressing the engine any more than you originally intended to do.
Good luck.
Good luck.
Nick
A.R. Headers
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