BBC Cylinder head & Intake manifold

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amc fan
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BBC Cylinder head & Intake manifold

Post by amc fan »

I was walking around the pits at the Penna Dutch classic this weekend, looking at the cars and I saw a 68-70 Nova A/S with new Gm Performance repo heads and intake. My question is are the new heads closed or open chamber? Is NHRA going to let them use open chamber heads? I would also be interested to know if the new intake is the same as the old one, or an enhanced/improved flow version of the 163. Any one know or care to guess the flow on the new GM parts?
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Re: BBC Cylinder head & Intake manifold

Post by 1980RS »

amc fan wrote: Tue Sep 21, 2021 10:36 am I was walking around the pits at the Penna Dutch classic this weekend, looking at the cars and I saw a 68-70 Nova A/S with new Gm Performance repo heads and intake. My question is are the new heads closed or open chamber? Is NHRA going to let them use open chamber heads? I would also be interested to know if the new intake is the same as the old one, or an enhanced/improved flow version of the 163. Any one know or care to guess the flow on the new GM parts?
My good friend races an A/Stocker '69 Camaro and he uses the NHRA approved 401 heads and the GM Bowtie intake, the heads I think are 118cc chambers and are an open chambered design. As for the intake it looks just like an RPM performer but on the dyno he says it's worth a tenth over the 163 intake and most use them now.
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Re: BBC Cylinder head & Intake manifold

Post by amc fan »

I remember about 20 years or so ago a friend was restoring a 69 RS / SS and he had L89 heads with the "snowflakes" and they were setting in an unheated garage for some time and the aluminum threads became "crumbly" or corroded and we had to Helicoil all the sparkplug holes and wound up doing the carb pad , rocker studs, and valve covers holes also. I think it is great GM re popped the heads, and intake. Mopar and Ford should do the same. You can only do so many valve jobs and head resurfacings and the heads start to loose performance.
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Re: BBC Cylinder head & Intake manifold

Post by Ron Miller »

FYI, the NHRA approved heads and intake are casted by Edelbrock for GM. =D>
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Re: BBC Cylinder head & Intake manifold

Post by DCal »

Ron Miller wrote: Wed Sep 22, 2021 4:54 pm FYI, the NHRA approved heads and intake are casted by Edelbrock for GM. =D>
Those 401 heads are much smaller cc wise, maybe 105cc I can't remember exactly. The spark plug is relocated closer toward the center of the bore and the plug boss is enlarged and of course also moved. In fact it's moved so much that a normal hollow dome BBC forging can't be used.
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Re: BBC Cylinder head & Intake manifold

Post by 1980RS »

DCal wrote: Wed Sep 22, 2021 5:21 pm
Ron Miller wrote: Wed Sep 22, 2021 4:54 pm FYI, the NHRA approved heads and intake are casted by Edelbrock for GM. =D>
Those 401 heads are much smaller cc wise, maybe 105cc I can't remember exactly. The spark plug is relocated closer toward the center of the bore and the plug boss is enlarged and of course also moved. In fact it's moved so much that a normal hollow dome BBC forging can't be used.
The ones my friend used was telling me his are 118cc's, but like a lot of guys who race in those classes they are not to honest about what they are building. :lol: I have his old ones I got for $400 after he said the head guy ruined them, they sure look good to me and flow some great numbers. I cleaned up all the junk in the ports from the factory and have to redo the exhaust seats but for that price I can sink a buck or two in them to try out on something.
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Re: BBC Cylinder head & Intake manifold

Post by DCal »

1980RS wrote: Thu Sep 23, 2021 1:37 am
DCal wrote: Wed Sep 22, 2021 5:21 pm
Ron Miller wrote: Wed Sep 22, 2021 4:54 pm FYI, the NHRA approved heads and intake are casted by Edelbrock for GM. =D>
Those 401 heads are much smaller cc wise, maybe 105cc I can't remember exactly. The spark plug is relocated closer toward the center of the bore and the plug boss is enlarged and of course also moved. In fact it's moved so much that a normal hollow dome BBC forging can't be used.
The ones my friend used was telling me his are 118cc's, but like a lot of guys who race in those classes they are not to honest about what they are building. :lol: I have his old ones I got for $400 after he said the head guy ruined them, they sure look good to me and flow some great numbers. I cleaned up all the junk in the ports from the factory and have to redo the exhaust seats but for that price I can sink a buck or two in them to try out on something.
Well I stand corrected. I called a few A/S guys and the heads are 103cc AFTER they flat and angle mill the heads to get close to the closed chamber head ccs. They are 117-118 as delivered. sorry guys
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