I am getting ready to start my motor build up but have a few questions on piston selection. I am building a 750 using 695/800 heads, they have 900 size valves. I know a few members hear have put 900 cams and valves into the 750 heads, I want to make sure that they did not run into any piston to valve clearance issues. Also I was thinking of checking the clearance with clay during assembly just to be sure, would the base gaskets have to be repalced after torquing to check clearance, or are they ok to reuse?
The only part of your question I'm sure of is the gaskets are reusable.
you should have plenty given you'll have to run a very high comp 750 piston to allow for the much larger chamber and most high comps have deeper cut aways. but you'll have to try it and see. the 800 cams are not as long as the 900 ones either so that will also help. and it depends on what cam timing you want to run as well.
your choice of pistons off the shelf is not large so i'm guess ferracci 12:1 will be it.
Thanks for the info I'm hoping to get started on this project soon