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Old 03-17-2005 | 09:14 PM
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Default Re: Aluminum heads

Originally Posted by WETTE VETTE
The worst part is when getting a cam ground one of the questions will be what type of exhaust. In the boating world we spend 3+ grand on systems and in reality many of us should be telling the cam grinder our exhaust really suck compared to true headers and flow more like HP manifolds. Instead I'll bet a lot of guys tell the cam grinder "my exhaust system is top of the line and flow great" and then end up with an incorrect custom ground cam! My advice is to buy a cam from a reputable marine engine builder who knows what CMI E-top, Gils, etc. exhaust systems are.
you are right and with these exhaust systems you need to help even a good set of heads the cam may get it out of the head and that is it also on a blower motor pushing the exhaust also helps in cooling the exhaust valve and we all know that is a weak link with the heat of a blower motor
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Old 03-17-2005 | 09:23 PM
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Default Re: Aluminum heads

Anybody ever flow the big buck headers, I wasn't impressed. That's the reason I asked about a 12 to 14 degree seperation between intake and exhaust.
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Old 03-17-2005 | 10:10 PM
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Default Re: Aluminum heads

Give it a shot GPM!! At the RPM levels you turn you may just be on to something. I could see the added exhaust duration allowing some cylinder pressure to be lost in the lower RPM's, but at 7500 there isn't much time for too much to sneak out!!
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Old 03-17-2005 | 10:16 PM
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Default Re: Aluminum heads

Originally Posted by GPM
Anybody ever flow the big buck headers, I wasn't impressed. That's the reason I asked about a 12 to 14 degree seperation between intake and exhaust.
you might be surprised it works on my deal tried it both ways
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Old 03-18-2005 | 07:41 AM
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Default Re: Aluminum heads

I'm done. I'll just keep doing what I have been doing.

Chris
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Old 03-18-2005 | 10:47 AM
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Default Re: Aluminum heads

Originally Posted by GPM
Anybody ever flow the big buck headers, I wasn't impressed. That's the reason I asked about a 12 to 14 degree seperation between intake and exhaust.
Ah yes.. we have a winner!

However, to some, since it's not in any catalog, a camshaft with 12*-14* of exhaust bias must be wrong!



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Old 03-18-2005 | 01:05 PM
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Hey Mike: We talked several times in Miami, and I know your stuff works. Maybe you have tested a combination that answers my question from above.

Suppose you have good aftermarket heads with the kind of exhaust that most of us a using, e-tops or maybe sport tubes. Your flow numbers are in the 375/250 CFM range at .600 lift on intake/exhaust. You try increase exhaust flow by:

a) porting
b) duration
c) both porting and duration

What has been your experience if you have done this back to back? Of course I'm thinking blower engine. Not after specific trade secrets here, just whatever you can share.
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Old 03-18-2005 | 02:05 PM
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Tomcat,
You may also want to try www.speedtalk.com there is always good info on there with some of the HP gurus's frequenting the board. The board owner Don, is an X cup engine man.

Chris
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Old 03-18-2005 | 02:27 PM
  #59  
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Default Re: Aluminum heads

IF you're still interrested in Canfield Heads, let me know. I can get you a good price on them. I have 2 sets of 310 CC Intake, 119CCC Cumbuston Chamber, Inconel Exhaust Valves, all Feria valves, 2.25 Intake, 1.90 Exhaust in stock, ready to go, 1 year warranty. I can even deliver as far as Buffalo, or even meet you near closer to Rochester. They are as cast with a CNC'd Combustion Chamber. Good price. Better than edelbrock.
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Old 03-18-2005 | 04:47 PM
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Default Re: Aluminum heads

Not wanting to fuel any fires here. I was looking through the cam books today, and I noticed a lot of the Nitrus cams run 14 to 20 degrees between intake and exhaust. I'm guessing it's because of everything that's being forced into the cylinder needs to get out. My question is, what would be the difference between, Nos adding 400 hp, or boost adding 400hp.
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