BBC head swap
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BBC head swap Ok I have the 90SS engine with peanut ports Im looking at changing the heads. I've seen two that will work with the intake which is upgraded now.
14081052
14092359
both show that they work within the same year but what about performance over the peanut ports. This engine is putting out 340 hp with a cam and larger TBI unit. If i change the heads and put a copper head gasket in it will up compression and breathe better with better heads. This should put me into the 400 range nothing to crazy. Any comments on the heads or other suggestions?
14081052
14092359
both show that they work within the same year but what about performance over the peanut ports. This engine is putting out 340 hp with a cam and larger TBI unit. If i change the heads and put a copper head gasket in it will up compression and breathe better with better heads. This should put me into the 400 range nothing to crazy. Any comments on the heads or other suggestions?
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You have a lot to consider.
I'll assume the heads you have now have 118 CC chambers.
The first head you listed is a semi closed chamber, thats going to raise the compression, which is good.
But if your cam has you at 8:1 SCR and 6.8 DCR you might end up with too much DCR and run into detonation problems.
One thing that I can't make sense of is this. Of all the big block heads out there, why are you saying only two will work with your intake?
As long as the port size is the same all 9.8 deck BBC intakes interchange from the 60's all the way up to the 90's TBI intakes.
Same with heads, they all interchange from the 60's to 1991, and from 1992 and up you just need a different head gasket and rocker studs.
But going from peanut port to large oval, even if the comp stayed the same will see a noticeable difference, and if you raise compression to match the cam, even more of a difference.
I ran my truck with Large ovals and a peanut port TBI intake and had a big SOTP difference.
I'll assume the heads you have now have 118 CC chambers.
The first head you listed is a semi closed chamber, thats going to raise the compression, which is good.
But if your cam has you at 8:1 SCR and 6.8 DCR you might end up with too much DCR and run into detonation problems.
One thing that I can't make sense of is this. Of all the big block heads out there, why are you saying only two will work with your intake?
As long as the port size is the same all 9.8 deck BBC intakes interchange from the 60's all the way up to the 90's TBI intakes.
Same with heads, they all interchange from the 60's to 1991, and from 1992 and up you just need a different head gasket and rocker studs.
But going from peanut port to large oval, even if the comp stayed the same will see a noticeable difference, and if you raise compression to match the cam, even more of a difference.
I ran my truck with Large ovals and a peanut port TBI intake and had a big SOTP difference.
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Bad info is why I looked at the two heads shown. I've been told the vavle train is not adjustable and I need Tbi heads that will work with the Peanut port intake. The cam and the TBI have been updated to produce 340 Hp with the heads on it now from the the 225 it had. I don't want to spend the money for the Edelbrock heads so if there is a set that would work better please advice. I can change the gasket to increase the comp but still unclear about the head choice from what is currently available. The current heads are 113cc
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Bad info is why I looked at the two heads shown. I've been told the vavle train is not adjustable and I need Tbi heads that will work with the Peanut port intake. The cam and the TBI have been updated to produce 340 Hp with the heads on it now from the the 225 it had. I don't want to spend the money for the Edelbrock heads so if there is a set that would work better please advice. I can change the gasket to increase the comp but still unclear about the head choice from what is currently available. The current heads are 113cc
If you have 1990 heads they have an adjustable valvetrain.
I'd look for any large oval head with combustion chambers no bigger than what you have.
Some more common numbers (last three digits is what most people go by) are:
702
290
063
It's getting hard to find good, factory, large oval closed chamber heads.
You might consider vortec big block heads, they have a small chamber, lg oval ports. You just need the right head gaskets to put GEN V heads on a MARK IV block, and rocker studs to adapt to adjustable valvetrain.
I have had my peanut port TBI intake and all the brackets off my 1992 GEN V (non adjustable valvetrain) on a 1984 454 with 781 heads. Everything bolted right up.
Right now my truck has all the TBI and brackets on a 1987 454, I removed a carbed intake and put my TBI in it's place.
Last edited by All Black SS; Dec 14, 2008 at 03:47 PM.
