so i have a 72 350 with the 7a heads and the garbage low compression original pistons--the cam in the engine is a crane 272H with 216 228 duration at .050 and .484 .512 lift---the engine is currently overcammed with that low compression---i was thinking about putting the speed pro l2320f flat top pistons in it to match the cam better. it has a edelbrock 3711 performer intake. would this be a streetable combo? its in a 72 delta 88 convertible

 

With the deck averaging about .025 on stock blocks if the heads are un milled and the deck surface untouched. With a .040 head gasket. Your compression will fall in the high 9's. 9.7x ish. Give or take. It's close

 

I have those L2320F pistons (.030) in my '72 7a head motor as well and my compression is right in that 9.7-ish range. Using a Howards CL510011-12 street cam and E-brock 2711 intake . They're not the newest or lightest SBO piston upgrade available but they still make for a solid improvement over stock.

 

If you don't have a lot of wear in the cylinders but want to clean it up a bit then you could even consider the new 4.065 bore Mahle piston.
It has a more modern ring pack and 10cc valve reliefs but is taller than most other aftermarket pistons. With a stock 7a head you’d have about 9.25:1. I’d say pretty ideal in your combination.

 

As cutlassefi suggested, have a good machine shop check the bores and "machine hone" for those Mahle 4.065 pistons. I got a set from him and they are quality and night and day difference from the Speed Pro's I always used. Jmo.