Head casting number
#1
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Car: 86' IROC
Engine: 388
Transmission: Built 700r4
Axle/Gears: 3.08 non-posi
Head casting number
My head's casting number is 3947041, here is the info i got on the head 3947041....69-70...302/350......"Right angle" casting identifier, 64cc chamber, accessory holes, good HP head
my question is what is the size of the intake runners?...would it be the same as the 3947041X head (165cc intake runner)?...also i have google the casting number several times and i keep getting 64cc and 76cc combustion chamber sizes and im not sure which is right.
my question is what is the size of the intake runners?...would it be the same as the 3947041X head (165cc intake runner)?...also i have google the casting number several times and i keep getting 64cc and 76cc combustion chamber sizes and im not sure which is right.
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Car: 88 GTA "Cocaine"
Engine: 350 tpi
Transmission: 700r4
Axle/Gears: 3.27
Re: Head casting number
what did they come off of
most of the guys who are know this kind of stuff are not always looking to talk about that old of stuff on these boards
maybe a corvette site
I dont know
most of the guys who are know this kind of stuff are not always looking to talk about that old of stuff on these boards
maybe a corvette site
I dont know
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Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Re: Head casting number
They're pretty much identical to the 186 castings. Couple different intake valve sizes, either 1.94 or 2.02. 64cc chambers and 160cc intake ports. The "x" versions are same except +5cc's on the ports, if memory serves me correct.
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Car: 86 iroc
Engine: 383HSR
Transmission: custom 700r
Axle/Gears: moser 9" 3.90
Re: Head casting number
the runner vol btween the two heads is more than likely the same ,163cc as the factory heads almost all have pretty small runners!
as far as the combustion chamber vol. could be either only way to know would be to measure yourself. hope this helped
that is a great casting though with some clean up! i have a pair myself
as far as the combustion chamber vol. could be either only way to know would be to measure yourself. hope this helped
that is a great casting though with some clean up! i have a pair myself
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Car: 86' IROC
Engine: 388
Transmission: Built 700r4
Axle/Gears: 3.08 non-posi
Re: Head casting number
I plan on porting and polishing them hopefully get some more flow out of them...im building a 383 so do u think these heads will flow enough after the port and polish?
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Car: 88 GTA "Cocaine"
Engine: 350 tpi
Transmission: 700r4
Axle/Gears: 3.27
Re: Head casting number
man these guys know their shizzel
I dont know if I will ever get that technical with stuff
the guys on thirdgen.org
ROCK
I dont know if I will ever get that technical with stuff
the guys on thirdgen.org
ROCK
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