The oem motor was the 5.7L 2brl, 210HP at prop. If I recall correctly, it touched on 51mph. I added vortec heads, dual plane, 4brl. GM/Merc roller cam, etc. I figured it was equivelent to the 5.7L EFI Gen+. Sold it last year and replaced it with a pontoon boat. 1st grand child was born...