I ported a set of 416 heads. Had them flowed at a local shop. I think it may be wrong. I have ported a lot of heads but have never flowed any. Studied porting for 8 years but still never flowed any. Here are the numbers they showed.
lift in/ex
.100- 71/53
.200- 133/96
.300- 178/121
.400- 213/159
.500- 243/180
.550- 249/191
.600- 258/194

That don't seem possible. Those are really high numbers. They had tubes bolted to them. Would that make a difference? I am looking for advice, is this even possible. I want to find another place to flow them. I have full race 2.02/1.625 valves with unshrouded polished chambers. I did everything I have ever read (from all the pro in the world) to them. But, still that don't seem possible. What do you think? Thanks to all in advance.

 

That looks BEYOND outrageous.

I'd be expecting to see numbers in the low-mid 230s.

This sort of thing is like dyno numbers: the ABSOLUTE reading you get is almost irrelevant, what matters is HOW MUCH WHAT YOU DID CHANGED THEM. So I'd be expecting that had they flowed those same heads on the same bench with the same setup the same the same the same BEFORE porting and then again AFTER, they would have got the usual 20% or thereabouts of change, instead of 35% from known stock numbers to ... that.