i was wondering if anyone could tell me what the intake and exhaust flow numbers (cfm) were for the iron centerbolt L98 heads, and the combustion chamber size.

im building a motor w/ forged bottom end, and plan on running the new 206cc vortecs, but was wondering if it would be in my best interest to run these L98's i have to save me some money for now; w/o scimping out on quality in the long run.
thanks.

 

The iron "083" TPI heads flow 202 and 141cfm in stock form.
The Bowtie vortecs are way ahead of this. The Nominal chamber size is 64cc.. You have to cc yours.

If you want to put in the effort you can expect around 230 to 240cfm from a honest complete "home port" effort on these heads.
That means fully ported, W/2.02x 1.60 valves, not a little bowl work.
Pros with a flow bench get more but you should be able to make a decent 425hp head out of them.

The bowtie vortecs are very good heads.

rhuarc30 is the TGO resident expert on porting 083 heads.
Here are the links for his threads on these heads
https://www.thirdgen.org/techbb2/sho...&threadid=96065
part 2 https://www.thirdgen.org/techbb2/sho...&threadid=97882
part 3 https://www.thirdgen.org/techbb2/sho...threadid=101489

 

thanks very much ffor the quick reply

 

Vortecs are awesome budget motor heads. I see a lot of vortec headed 5.7L cars running high 11s. Just great heads.

 

There are, I think, three sets of flow numbers on stock 083 iron TPI heads here:

https://www.thirdgen.org/forums/tbi/...-headflow.html

IIWY I would look at the average numbers across the heads rather than focus on one set of numbers... because the data comes from different sources & flowbenches.

There's also several ported examples, plus flow data from other contemporary GM heads. HTH.