Merlin 320cc, grumpy special head flow?
 

Have a chance to buy these merlin 320cc iron heads, grumpy special casting. Ho does these heads flow? Going on top of 9.7 to 1 compression, 509cid engine with gm zz502 roller cam. Are these any better than merc stock rec-ports. These are virgin set but would be bowl ported with good seats.

bring a sbc 1.50" exhaust valve w/ you,if you can run it thru the exhaust port,they can be made good.just have to watch out for breaking into the water passage by the short side radius.

They need work, as cast they are barely better than stock,Id buy the EQs over them fwiw