Something to think about;
1 degree change in cam timing works out to about 1.25 to 1.5 psi cylinder pressure. So a 3.5* change (about 1 cam size if both are straight up), is ~5 psi difference. To drop the pressure from 200 to 165 is 35psi. That's a lotta lotta degrees.How many teeth on a sprocket?
Yes it does make a difference.
with aluminum heads;
You are at the top of the scale there; the highest reported pressure I have seen on FABO is 200 on best pumpgas with aluminum heads.
I have run my 367 at up to 185 psi on 87E10 with full timing.