308 Vs 915 exhaust ports

[67/6barracuda]

I have read through out the years how superior the 308 heads are compared to the 915. I just removed a set of 308’s off my new to me 360 project, one head is cracked for sure the other would need to be fluxed and pressure tested. I see the combusting chamber is slightly better in that it’s visually smaller, but so is the intake and exhaust ports by a significant margin. The bowls appear to be better in the 308’s, but i would need to do some serous hogging to get the exhaust ports to open up compared to the J’s. Those 308’s ports appear to be 318 exhaust port size to me. I will run the 1.88 J’s they should clean up nice.

 

[yellow rose]

Bigger usually isn’t better on the exhaust port.

 

[MOPAROFFICIAL]

I have read through out the years how superior the 308 heads are compared to the 915. I just removed a set of 308’s off my new to me 360 project, one head is cracked for sure the other would need to be fluxed and pressure tested. I see the combusting chamber is slightly better in that it’s visually smaller, but so is the intake and exhaust ports by a significant margin. The bowls appear to be better in the 308’s, but i would need to do some serous hogging to get the exhaust ports to open up compared to the J’s. Those 308’s ports appear to be 318 exhaust port size to me. I will run the 1.88 J’s they should clean up nice. View attachment 1715608036View attachment 1715608039View attachment 1715608040View attachment 1715608042

Maybe use stainless valves and no hard seats, round the ssr and do a good bowl job with a hair of venturing on the far side.
They both will do good, 308 better. In the end I'd love to see a identical 260 cfm from both @.500 and then the diff exhaust flow of each on the dyno..