[Scotch]

Originally Posted by 4OfaKind

The application is for a street driven car that will see time on road courses. So the rev range will vary. No endurance stuff, maybe 5 laps at the most. The vehicle will be heavy about 3500lbs.


So a low-rpm torque monster is really what you're after. Pump gas, lots of throttle response, and no need to go past 6,500 rpm or so. How's that sound?


The heads are a whole different story that will require another thread, so for now assume they are big enough and exotic enough to feed the need. My focus is the ability to stuff a large crank in a small block and how long it will stay in there. Basicly doing it because I can (if I can ).

I get it. While I appreciate your angle, the capabilities of the big-inch small-block crate engines out there serve the need. Otherwise, if you really want to build this within the confines of a stock small-block, there's plenty of potential in a 406 to make the kind of power you're looking at.

The thing is...once you decide to go after that other 40-50ci, you really want the raised cam/taller deck to make it work for you. You need to give that crank room to swing and you want to run good connecting rods, and they need clearance too! You don't want to be grinding the rod bolts down or notching the bottom of the cylinder bores if you don't have to. To get a bunch of stroke into a stock block would require these kind of clearancing techniques and while they've been done before, they are also the reason the aftermarket tall-deck/raised cam blocks were engineered in the first place!

So, I'd have to recommend either a very serious 406 or an aftermarket block-based 450-ish inch setup. Based on what I know, which ain't as much as lots of other guys, but is a little more than most, building torque will not be your challenge here. Putting it to the ground will be. I think if you've got 500-550 ft-lbs being put down without tire spin, you will be a happy guy. You can make that kind of power with a very serious 383 or a very good 406. A mild aftermarket block-based 450-plus inch SBC can do even better at lower rpm.

~SP~