what would be the best sbc for a mud truck
 

Im looking for some ideas . the truck runs in stock classes it is a full body right around 4300# it has a good th350 4200 stall and a np208 and 410s running 38s for the most part im open other then stock fuel pump and 3/8 line right now im running a 358 12.1 with world heads but now its come down to i need more motor i was thanking maybe a 397 or so thanks for any in put

Of course the bigger the motor the more hp and torque. Do you have any ci limits?
Go as big as you can. Most sbc guys go with a 434.
If you don't you'll just end up building a bigger motor sooner or later anyway. That's what happened to me. Started with a 509, then 548 then to a 632. Should have built the 632 in the begining.
1- Do you have to pull vaccum??
2- What type of mud do you run, Deep or fast Track?

These things will get you faster without working on the motor.

1- Loose some weight on the truck.
2-Ditch the 350 and get a Power glide
3 -With those gears you're still running the low side. High side is faster.
Tell me about the suspension and your limits. (rules).

I don't have a ci limit but i would like to stay with a sbc i don't need any more weight on the nose and my truck is cut as much as i can it has to be a full body full size truck and there is a few guys running 434 but believe it or not i can beat them and have from time to time my truck works great that most of how i get away with a 358 and win by the way its more of a bog truck with a little bit of side by side from time to time

i cant run a glide cuz its not what the truck came with i don't have to pull vac and my suspension is 4 leaves on each corner and with a 3 link out back other rules are must have a stock fuel pump and 3/8 line and iron headed and one carb

Can you post a copy of your class rules. Or just give me a link to you track. As you know mud bogging is so different in every area.
Just because you out run a 434 with a smaller motor deosn't mean 434's aren't good. It's all about the total combo. Just think how much faster you would you if you had the bigger motor.

Motor wise and stock fuel pump some of you guys help me out on that part too.

The truck part I can help no problem.

4,300lbs is still to heavy for a full size truck with a small block.
You should be able to get in the 3,900lb or less range with a 200lb driver.

You have to run a trans that came in the truck? Can you run a trans brake?
I need to know what you can and can't do with the rear leaf springs.
How many springs do you have to have?
Can you run adjustable shocks?
Can you run coil over shocks?

thank you so far im some what new to this sport you can see the rules at www.funrunmudrun.com i run the 35 stock and 38.5 stock let me know what u thank

I'll look into the rules and get back with you. Will probably be Monday or Tuesday before I have a chance to get back to you.