Another Motor Oil Thread

[Jetaholic]

I just built a 454 for my jet boat. The cam has already been broken in and I'm giving her an oil change before she goes in for upholstery.
My question is, what weight/type oil should I run in this thing? This motor is calculated to be close to a 500HP/500 ft lbs motor with a max RPM of 6000 (probably only see about 5200-5300 RPMs though). Here are the specs on the motor.
454 + .030" over (460)
TRW L2465F forged pistons
Stock crank and rods
Clevite bearings (std size)
Melling M77G oil pump
Comp Cams double roller timing chain
Iskendarian 280H Mega cam -
280 Seat-Seat duration
232 .050" duration
.549" lift (1.7 rocker ratio)
60* overlap seat-seat
12* .050" overlap
Cam degreed 4* advanced
MSD Ready To Run marine distributor
Holley mechanical fuel pump
353049 heads w/ 2.19" intake/1.88" exhaust valves
Isky super lifters (anti pump up)
Comp Cams magnum push rods
Scorpion roller rockers
Edelbrock Performer RPM Air Gap intake manifold
Marine Holley 750DP Carburetor

[River Rat 005]

I got a motor that specs about the same. When I was running it, I ran 10w30 and some times 20w40 Valvoline. Never tried synthetic back then. In the race motor, I run 5w30 Mobil1. Haven't had any trouble with either. I think it's more run what you want after you read all theses threads.

[ck7684]

Run the lightest oil you can while maintaining good oil pressure. I would think 5W30 on a fresh motor would be fine. There's no benefit to pumping thicker oil through then you need to...