built engine on regular pump gas?

[riz]

What's the highest HP a guy can get when building an engine and still be able to run regular pump gas?

RIZ

[BigBlocksRule]

How big? I have a 565 on a stand that should make around 725 - 750.
If that's not enough, you can go with a tall deck block for a 665 and be closer to 900.
The only thing better than cubic inches is rectangular dollars

[406 Q-ship]

Well if your going for regular fuel engine, I am going to assume that MPG might be a consideration too. There is no reason you can't do a nice 9.5 compression 350 with aluminum heads that will get 400 lbs/ft of torque. Forget HP numbers that is just advertizing number, torque is what moves you. If your real careful and play with quence areas the compression can be bumped up to 10.5 and picking up more torque. A 400 SBC when done right makes big block torque and pulls down small block mileage. The 406 in my Monte Carlo gets 17 hwy and is not set up for mileage at all (it will run 12.90's at 106 MPH weighting 4000 lbs).