The data I found stated that the testing was done at 28" H20 or 28in H20= 2.060 in Hg
Dynomation only accepts 1.5 or 3.0 inHg, since that is how 2 bl and 4 bl carburetors are rated.
Lets keep it set to 1.5 inHg since that is closest.
Simulation programs are better at spotting trends and not so much at predicting absolute
numbers. Another words, better at comparing engines.
I also noticed that the combustion volume you listed was 84.3cc while mine was calculated at 84.0cc (not sure if this is big enough to make a difference)
It's not going to make much difference, but just to prove it to myself I made the necessary changes. Then
I compared to two graphs and they were essentially on top of each other, so maybe 1 or 2 HP difference.
I also saw that you listed the intake running diameter as 1.890 inches which matches the intake valve size, but the exhaust running diameter is listed as 1.500 when the exhaust valve diameter is 1.550
OK, I looked over the settings in Dynomation and I don't have a way to control that. Evidently it was telling
you the assumptions that it was making. But that was good catch, you are paying attention !!!
I believe there is a lot of room for improvement on these heads and plan on porting and polishing them. The flow numbers I had were for stock un-ported/un-polished heads. Although I am not sure how much improvement I can expect (especially as this will be my first set of heads I port and polish).
@Grumpy may have an opinion on this, let see what he has to say.
You say Port & Polish .... what exactly do you have planned ?
I went through the report line by line and the numbers look good (see post above for what I did notice). I am not sure if those things are a big deal or not.
Thanks for doing that, not everyone goes to the trouble ! It shows your attention to details and an interest
in getting this engine built correctly.