Thoughts on Valve size?

I'm not actually sure what the car would weigh.
Thanks for your input Frosty.
The "next" engine will get a pair of J heads with 2.02's etc. (I actually have the heads already) This build is to use up the other parts I have first. I really want to run forgies in the next build. but keep the CR low so as to run Barametric compensators/amplifiers on it.
I have so much on with a young family, and too many projects that build might be a while off.