470 going to the dyno - HP/TQ estimates
Looking the exhaust numbers over further…….
While the high lift numbers are certainly reasonable, the low lift numbers(thru .400) are better by a bit than what I usually see…….particularly .200 lift.
But none are over 100% c/d.
Indy changed the cnc program on the exhaust port for the SR head a few years ago.
It used to be the same port as the cnc 325 and 345 -1 heads, and now it uses a unique program that has a smaller opening.