That 450 horse you're after is awfully different in a TF than a late model car. With a straight axle, these trucks drive like.....a truck. Very easy to get into trouble and not get out of it before it's too late. Can you build an engine and drop it in that will meet that number? Yes, easy. But it won't likely be enjoyable. Especially if you're pulling it out of a 350 cubic inch engine. That puts it to probably 500-525 horse at the crank, assuming a manual transmission. That's 1.5 hp per cube. Figure idle speed will be 1000 rpm, don't expect to drive it below 2500 honestly, even light throttle, it will buck and stumble, it will require lots of tuning to get dialed in properly, be high maintnance, and drink lots of gas.
I'd build something more moderate, focus on torque and low speed power, regardless of engine size. That will give you the seat of the pants feel you're after without breaking the bank, and be much more enjoyable to drive in an old truck.
Devin
