i've got a queston that has really piqued my interest.

i've got a roller cam 350 block sitting in the garage that i would like to build, and i'm starting to lay out the different parts on paper. i may not even keep this as a 350, i might build a 383 or a 396 stroker out of it

what's got me thinking would be related to cylinder heads. as a general rule, how much airflow is too much for street-driven small block? i'm looking to cross off a couple of heads from my list. i'm pretty sure that a 220cc intake runner wouldn't do me much good for the street, unless i built a stroker 383 or 396.

i haven't picked a camshaft yet, so i'm looking for a general rule for cylinder head flow for street use. something with a cnc runner option would be nice. i can save up more money for that

thanks!

 

Read this thread here.

 

That is a hard question to answer, depends on what you build, what you want, weight of the car..lot of variables that go along with that question. On a 383 a 300 cfm 220cc runner is good to around 7000 rpm, a 270 cfm 195/200cc runner is good on a 355 to the same rpm, a 330 cfm 235/240cc runner on a 396 to the same 7000 rpm....these are BALLPARK numbers....alt of it depends on the rest of the combination.



David

 

That thread should really be a sticky.

One of the best explanations of "practical" head porting I've ever read.

 

Ya can't put to much head on it. For a 383 ya need 300+CFM. 300CFM will make 615FWHP if everything else is spot on.Some of the SB2 headed ones are making 800+FWHP. Don't worry so much about the runner size and get the flow numbers. Ya don't loose low end from the head,ya loose it with a big stupid cam most people put in them.
BIG heads=Smaller cam for the same HP.
People are running SB2 heads on them that flow close to 400CFM and a hell of a lot more runner than a 220CC. Buy the largest head ya can afford and build your engine around them.