355 cu. in.
Carburetor: 600 vac secondary
Heads: GM L31 Vortecs,
Intake: Edelbrock Performer RPM Vortec
Camshaft: Comp Cams Xtreme Energy 268 , 224/230 of duration 0.050 (Corrected valve lift with 1.6:1 rockers is 0.508/0.512 in.)
Rockers: 1.6:1
Headers: 1 5/8 in.
Comp. Ratio: 8.75:1
MAX HP: 390 @ 6000
MAX Torque: 426 @ 4000

{{Taken from Ryans combo page}}


Here is a example of what you could close to do with your current engine, I would go a little smaller on the cam, a little less compression and use a roller cam to keep the torque number close to this and at a lower rpm.

Someone with a dyno sim could play with the numbers on compression and cams to get it narrowed down to a usable combo for your application.

I am betting with the right mix of parts you could still make 400 ftlbs at close to your crusing rpm at 65 to 70 mph.

I have no experiance with the load you wish to put on this engine...it looks like about 14,000 pounds in all, so I imagine the compression will have to be lowered to 8 to 1 or lower...I do not know.....

But with the right mix you can get 400 ftlbs or more I think and still not break the bank......step up to a 383 and I would guess at 450 ftlbs at about your current 65 mph rpm.......

I still say for about 2000 bucks you can do 400 ftlbs out of 350-355 no problem.

I would think once you went 383 and bought all the associated parts the budgett would be more than that..... possibly 3000 or less

I am sure pat could set you up with a mean big block towing engine that would smoke the tires on that thing for a good deal also.....

Not really sure what that would cost or what the other options you mentioned would cost........they all sound like plausable ideas to me.

Just boils down to how much money and time you want to spend on it and what makes you happy...........