I was told they flow about 265cfm out of the box. I was wondering how accurate that statement is. I'm trying to decide if I should spend the money to get my heads ported and polished before I stick them on the block which is getting a TSP 228R.
My thinking was to not waste the money porting stock heads, and just get the springs I want, and then later I can just buy some Dart heads or some other aftermarket head that will outflow an expensive port job on stock heads. What do you guys think?
Save the money and do a L92 head swap.
Gone, but not forgotten!
317s flow well stock. They have 71-72cc CC size and and D-shaped ports.
Going on a 6.0L?
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Yes sir. Forged internals, a TSP 228R, the 317's, an LS6 intake, and longtubes.Originally Posted by txarkitekt
a good set of heads are worth about 40-50hp to the wheels, see if that's worth it when compared to your budget.
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That number is about 15 CFM high. Stock 243/317 heads flow enough air to support 525-550 NA crank HP.
ive seent about 250 i believe for CFM
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it ain't that I'm too big to listen to the rumors, It's just that I'm too damn big to pay attention to 'em..That's the difference
They flow alot more if you force the air in!
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My stock 317's flow about 1028cfm lol
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That's the problem I'm facing. If you port the 317's you already drop well below 10:1 C/R with flat top pistons (have to factor in the valve reliefs). I'll have to find out how much they can be planed, and what to do about pushrods at that point.
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