Specs on the 350 will tell us what it puts out. Actually 400 HP is extremely easy to make, mine will be there with a head swap and install my mild roller cam. Even 450 HP is the old 350 HP for these motors, just not cheap. Talking 9.6 to 1 with a modern 1mm ring pack, aluminum heads and decent sized roller cam. Actually rogue_ryder just did one with the same bottom end as me, bigger roller cam and 64cc Procomp heads, just under 450 HP, like 437 HP. The new Edelbrock heads released next month would have tipped him over. I broke a No Slip on the 7.5" on slicks and exploded stock spider gears on the street. What other parts do you have in 7.5". You need Moser 28 spline axles, a strong posi and girdle cover to have any hope to survive. Good luck, you will need it.