Is there a difference in setting up a carb for e85. A buddy has a new carb that was just done for methanol. He's moving to efi. I figure by the 15% gas, it may not need to be so rich. 10:1 not enough compression to keep the alcohol in vapor form and combust efficiently? Iron head vs aluminum?

Everything in an alky carb is machined for more fuel flow. You can probably get it pretty close, but might still be a little rich under certain conditions. 10:1 compression should be fine for E85 on street. That's all production cars are, if not less.

A good alky carb will be way too rich on e85 without real work, and possibly changing boosters.

Just for a reference I run 150’s-152’s in my 850 on my small block

Some comparative numbers as well. Blown 572 E85 2X4 1250's 180's all 8, gasoline boosters

Nitrous 596 2x4 1250's E85 168's all 8, gasoline boosters

Blown 572 with 2x4 1050's with alky type boosters. ALKY 210's all 8

I tried once to jet down a pair of alky dominators to E85. Just way too much signal to ever get right. By the time I had them close I'd changed almost every aspect of the carb, including boosters, jets, emulsion jets, air bleed, squirts+cams, transfer slot, needles and seats, floats. Never again.

Way too rich

HP, and A/F,says on the money lol.

The best answer is fuel injection. EFI or mechanical