We did a basically stock 383 last year.Stock 906 heads, 8 to 1, torker intake , comp 230 dur. 480 lift hydro cam. Using stock exhaust manifolds. B/W 475 turbo. Holley 750 homebrew carb.
Made 586 hp. And 690 ft. lbs. torque at 4500 rpm.

I believe Dizusters 360 is making aprox. 800hp using stock manifolds.