I got a 350 SB & was wondering if anyone knows the CC size factory 350 heads have? I don't have like $260 and up to spend on each side of the engine & thought about modifying the factory ones to work on a performance street engine. Thanks guys.

Joe

 

Depends on the year and model of the heads. They could be anywhere from 76cc down to 58cc.

 

is there a way I can tell?

Joe

 

Casting number. Get it and look it up here: http://www.mortec.com/castnum.htm

 

350's came with various factory cylinder heads.

low performance "smog motors from the 70's and 80's typically came with 76 to 80cc heads.

Most 76cc smog heads can be milled down to 68-70cc range.

"High performance" versions typically came with 64cc to 67cc heads. A 350 TPI head is an example (083)

"305 head" castings are typically 58cc's. {can be millled for less cc (52 to 56) or deshrouded to increase chamber size (62-66cc range)}

Lots of choices there for a budget performance motor.

Exactly what head casting are you dealing with (casting number) Some of the factory heads are not worth modifying for more power (like 882's and 624's and 191 and 193 swirl port TBI) when other, better stuff is readily and cheaply available.

What ever head you use, when combined with machining and block decking and gasket selection can be made to have the right compression ratio with flat top pistons on a 350.

What cylinder heads do you have now and what are you trying to achieve out of it? The right cylinder head will make or break the success of your project.

 

ok I found out 74-80 350-400 heads 76 cc chambers

I want to build a good street 383 outta the block, any suggestions.

Joe

 

The only suggestion would be toss those heads in the trash.