Whats the most economical way to make 400 hp, 302 or 351

Tagged to see results.

A '96 5.8 should be a roller.

Do you want 400hp at the crank, or at the wheels? There's a big difference there. 400hp at the crank is easier to get than at the wheels...obviously. You can throw a well match h/c/i on a stock 302 and get really close to 400hp at the crank, whereas it'll probably take a stroker to make 400hp at the wheels. The difference in 5.0 vs. 5.8 is gonna be how far you can go with it, since the 5.8 can be stroked up to a 426, and stroker kits and block machining pretty much cost the same so do you wanna spend X amount of money on a 347 or that same or close to the same money on a 400+ci engine? Keep in mind that you may need to spend extra cash for the 351 swap parts, but IMO that's the way to go if you want that power...as i've seen well built h/c/i 408's make 500hp easy.

Most economical, period? You have a good motor. Install a 150 shot on it, few hundred bucks. My 89 motored 86 went 11.40's with an unopened(not even a valve cover came off) 5.0 with a 150 NOS kit(and a bunch of chassis work/practice). I would recommend rebuilding it anyhow, its old, but you won't necessarily get more power from a bigger motor.