Yes, I'm no engine or cam selection guru, but if you think about it most of the old stuff had more than 9:1 compression originally and then they get rebuilt at 9:1 or less to survive on todays gas. Once you add an aftermarket cam with a bunch of duration you loose bottom end and gain more up top. Problem is if you use stock heads they nose over just when the cam starts to get going.

You can crutch the too big cam situation by adding steeper gearing and a high stall convertor to get the engine into the upper part of the power range faster, but that can kill streetability as well.

My brother has build several Oldsmobile engines at 10:1 with factory iron heads and a moderate cam and they run fine on 91 octane here. If you listen to the machine shop guys they will tell you not to even try it.