too small
Those heads aren't even close for a 632", ..
the valve angle, chamber, portshape all make that a good head
for something 540" or smaller, .. but won't even come close
to hanging with current technology heads for big inch engines, ..
doubt you'd make close to 1000hp with them, .
Fully ported on my honest flow bench that head will flow about
430 cfm @ .9", .. FULLY ported with a 50* VJ, ..
I'm not really a fan of the Brodix oval ports unless you choose the largest
on they make, .. reason is the oval opening drives airspeed too
high, it's like using a head that's too small.
Curtis