MP 292H cam too big?

moper said

You have to look close at the details... The intake closing point should be 74° ABDC. The intake closing point at .050 is 37.5°. So you should be using 37.5+15= 52.5. Try that one...

Just to add... the calculated dynamic compression goes DOWN with a larger cam, not up. So if this cam was too large (I don't think it is...) then the dynamic would be low (in the 7s), not high (in the 9s).

Click to expand...

Thank you. That part makes a lot more sense now. I understand the CR goes down with larger cam. I originally meant to ask if this cam is too big for a street/strip car or for this build with iron, open chamber heads. Plugging 52.5 into the kb silvolite calculator I come up with: Effective dynamic CR 9.668. I must still be doing something wrong, otherwise why in the H would anyone ever buy the KB 191s with taller dome? I wish I had asked advice before purchasing (macnine shop recommended) pistons and paying to have all the machine work done. when I asked the machinist about using the 292H cam, he told me my cam was probably too big, that i needed to go home and get on kb silvolite web site and figure out CR (yes this is my first build). He told me that I was probably not making 10:1 static CR and therefore the cam would be too big.
It looks like (from browsing other posts) if I had just asked advice before beginning to spend money, the flat top kb 107s would have been, more often than not, recommended.
DYNAMIC EFFECTIVE COMPRESSION RATIO
9.668