Highest LIft cam with 68 340 with stock intake and carb

You can get a bunch of power out of the stock 340 intake. I run a 800 cfm thunder series on my 410 ci stroker through the stock intake and exhaust manifolds. Other than the stock carb being small from the get go gor the 340. The exhaust manifolds are the bottle neck. My lift is .558 on a cast iron x head. Its tough to go big lift on sbm heads that aren't w's