Cast Iron exaust manifolds for BB
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Pro
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From: phoenix az
Cast Iron exaust manifolds for BB
I have a set of iron manifolds out of an early 70s pickup truck. Both exit in the rear position (under #7 and #8) and have a 2.5 inch flange. Headers are such a pain and these manifolds should fit and still flow well. How much would I give up using these iron exuast manifolds with a 2.5 inch system as opposed to a set of headers with a 3 inch system. The motor is a high 12 second ride in my camaro with headers. I'm gathering up the parts to do the swap.
Safety Car
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From: Clymer PA
Re: Cast Iron exaust manifolds for BB (BubbaJJ)
IMO you will be giving up a good bit. The "How To Hot Rod Big Block Chevys" manual says that changing from cast iron exhaust manifolds to headers is good for around 50 HP (maybe more depending on how radical the motor is).
I'd say if you want to keep your Camaro a 12 second ride, stay with the headers.
I'd say if you want to keep your Camaro a 12 second ride, stay with the headers.
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Re: Cast Iron exaust manifolds for BB (BubbaJJ)
I agree with Bence. However, I'm considering the stock manifolds and 2.25 inch side exhaust as a comprimise over the Hookers.(wife :mad )
I don't think those stock manifolds will mate up to the stock Vette exhaust though. :(
I had a similar querry recently http://forums.corvetteforum.com/zerothread?id=403796
The end result was that the 454 manifolds are pretty model specific. To get the truck manifolds to work would require speciial pipe bending or fabricating at the manifold. I guess it could be done.
Len
[Modified by 1970 Stingray, 4:51 AM 10/23/2002]
I don't think those stock manifolds will mate up to the stock Vette exhaust though. :(
I had a similar querry recently http://forums.corvetteforum.com/zerothread?id=403796
The end result was that the 454 manifolds are pretty model specific. To get the truck manifolds to work would require speciial pipe bending or fabricating at the manifold. I guess it could be done.
Len
[Modified by 1970 Stingray, 4:51 AM 10/23/2002]
Le Mans Master
Joined: Sep 2000
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From: Orlando Floriduh
Re: Cast Iron exaust manifolds for BB (1970 Stingray)
Just a heads up here... Corvette BB manifolds are quite different. They are unique to Corvette and nothing else fits.. Headers from a Camaro may noy fit in a Corvette either.
Melting Slicks
Joined: Feb 2000
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From: Vancouver BC, Canada
Re: Cast Iron exaust manifolds for BB (silvervetteman)
'Corvette BB' manifolds are not the bottleneck on a stock engine, and can actually be modified to flow even better. On a modified BB, headers are required. Non-Corvette cast iron manifolds on a modifed engine is not a good idea.
Safety Car
Joined: Mar 1999
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From: VASS, NC, USA
Re: Cast Iron exaust manifolds for BB (Turbo-Jet)
Bence, I agree, the Corvette manifolds are a different fit. Truck/passnenger car BB manifolds of the same era may look the same, but will not fit in a corvette frame
However, the corvette BB manifolds were the best flowing STOCK exh manifolds of the time
However, the corvette BB manifolds were the best flowing STOCK exh manifolds of the time
Le Mans Master
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From: Orlando Floriduh
Re: Cast Iron exaust manifolds for BB (MELVIN)
Bence, I agree, the Corvette manifolds are a different fit. Truck/passnenger car BB manifolds of the same era may look the same, but will not fit in a corvette frame
However, the corvette BB manifolds were the best flowing STOCK exh manifolds of the time
However, the corvette BB manifolds were the best flowing STOCK exh manifolds of the time
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
Re: Cast Iron exaust manifolds for BB (guvnerwl)
I've got a set of vette BB manifolds laying around somewhere if you really want to go that way.
Len
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From: phoenix az
Re: Cast Iron exaust manifolds for BB (1970 Stingray)
Bence, Im putting the 454 thats in my camaro now in my vette, can't let you have all the fun :D . If it was a high twelve in my camaro, there's no reason to believe that it wont do the same in the vette. I'll just have to bite the bullet and get the headers.