I know I'm going to get a lot of opinions, but thats what I want. I have a 77 f250 and need to put in a new engine. What would you put in a truck for a powerful mud truck, something to turn some big tires and get her though the pits. Also what would you do with the diffs and transfer case. Ok try and do this with a modest budget in mind.

 

What do you consider "modest" in terms of budget and are you planning to use this as a competition truck or just for playing? If it's competition are you planning on mud bogs or mud drags? What axles/t-case/tranny is in it right now?

 

Well, is it strictly a mud truck?? If so, then you've got alot of options.

1. Engine- you're prob gonna want a big V8, like a 390, 429 or 460. MAybe upgrade the cam, and carb/intake. Exhaust is a definite upgrade, straight pipes all the way.

2. Diffs- From what I've read and learned from here, you're gonna want a real heavy solid diff, like a Dana 60 or 70. Something strong, solid and offroad proven. Be sure to have manual hubs, auto's suck. You're gonna want either a locker in the front/rear or both. Or you could just weld the spiders.

3. Transfer Case- A NP205 would be the best (I believe) option. If you can get a twinsticked one, all the better.

4. Tires- Well, heres where the most opinions/options came up. Big and fat, tall and skinny theres sooo many choices. Some big paddle tires mtd on good tough rims.

Ivan has a truck similar to yours (78 250), Im sure he and the other masters can help.

 

the terms, "Modest budget" and "big powerful mud truck" don't usually go together very well.
the cheapest way to go would be to drop in a used 460 with a C-6 and 205. these can usually be found in a junkyard for not to high of a price. who put the 302 in that thing? was it like that when you got it?
does it still have the stock axles? should be a D44 in the front and a D60 in the back. you could leave those in to save some money as long as you don't go to crazy in the motor dept.

 

WELL SAID. We get guys come in here all the time saying how they want to build the biggest and baddest. Well, thats fine and good but you gotta pay to play. I've got about 15k sitting in mine and thats with me doing all the work myself. So unless you think thats cheap...good luck.

 

If it is solely for competition, I recommend swapping the front hubs for half ton, and finding a 9" for the rear. Both are plenty strong for mud. Big Block for simplicity. Do all you can within the rules, headers , a good intake and carb, and ignition are almost mandatory. A C6, with a good stall, and a cooler, is your best bet tranny wise. If your gearing is relatively high, around 3.55 or so, it's better to leave the axle gearing alone, and go for an NP208. It's lighter, and with the deeper low range, makes 3.55's feel like 4.30's. You dont want a lot of gear, unless the motor can make power up high and is built to last at that RPM level. If you already have the 205, go with 4.10's. I prefer the (relatively) tall and skinny mentality, and choose to run 38x11-15 Boggers. They hook hard, and can work with many other, larger rear tires, should you develop the need(38x15, 39's, 44's). Lighter is better, but weak sucks.

As for just playing around, the tougher you build it Dana 60's, 70's, etc., the less often you break. For this, gear for however you want, and use the biggest baddest tires and axles you can find. the other guys are better at this than me, I'm just good at the first part.

 

Now i am part of the big 'n fat tires crowd, and on rigs with shorter lift i would go with either a 33x15 TSL (i think thats the one) or a 35x16 bogger (what i run). Now i am running a 400 in my mud only truck and to date i've done quite well. As for power for the 400 i'm going to use a set of cleveland 4v quench heads, nice juicy cleveland cam set from compe cams, get a set of intake spacers to adapt a cleveland intake to the 400 then run a torker intake on the top, i've also got headers (meant for a 460) that i'm turning into a set of zoomies for the 400, and i've also already got a holley dp carb for the motor too. Once said and done with i will have NO more than a thousand bucks (canadian) put into motor/tranny/t-case setup. But it will be built gradually. For you find either a 400 or a 429-460 that runs the best, do not pass up a perfect running rebuilt 400 for a 460 that runs, but thats all you know or vice versa.

Now the axles you have will get the job just fine and give you few worries if you sick with the 35" and under crowd (and you can beat on it too, ask me how i know). But if you can weld the rear up and leave the front open, or go with a rebuilt ls unit, again this helps with reliabilty of the front u-joints.

Then here's the part that will win you more bog then you think. Seal all the electrics the best you can, switch over to electric fans (search the forum theres a couple good threads), run all the breathers into the cab, mount the battery in cab, seal off the engine carparnment the best you can, get a K&N filter (or something of the like as i've seen paper filters disengrate and nearly get sucked into the motor), then the most important thing, LOSE as much weight as the rig possibly can, this means hackin the fenders out, removing the bed, put a racing type bucket seat in and get rid of the bench seat, replace the bumpers for pieces of 2x2 tubing, removing the front gas tank, and any other unnecessary items on the truck.

Oh you will not need a winch or anything of the like at the pits, just solid attach points (recievers are the best). Thats just my 2 cents from my project that is identical to yours.

 

Well, I should stay out of this thread but, you have heard both wide, and narrow tires, so here is a little more explaination. First if you are trying mud bogging go as wide as you can, and as tall as rules allow for the class you want to run in sometimes this can make or break you. second if you are looking at mud drags then go narrow dig harder and lauch better plus don't have to cut through as much mudso will be faster at half track and on (this rule changes when you start getting enough hp that you can't hook a skinny tire off the line) any case check the rules if superstock says 35, and smaller (pretty typical) then go with something like a 35x10.50 bogger (I run mud drags so the rest of this is dedicated to that type of racing) another one is the 34x9.50 swamper they are really good. Now some one mentioned twinsticking a np205 don't bother waste of money, and time plus added weight even if only a small amount in a pur mud truck you don't want it. Another thing someone mentioned manual hubs once again no, not in a compition only vehicle run with a full time drive flange (fewer parts to break). Next go with a big block if you can, small blocks can win but you better have it built strong, and really plan on turning some RPM's.. Next lighten the truck as much as the rules allow gutting everything you can no bumpers I even take the supports out of the hoood and cab. if yo never plan on running it on the street take out all the lights and wiring stock fuel tanks etc. Mustang started mentioning it but put your radiator in the bed and totally close off the engine compartment keeps the mud off the engine, and out of it. run a K&N filter with a nylon cover available for them this will keep stuff out of the intake. put your electronics inside the cab. If you are running straight line then lock both diffs either with spools or welding the spider gears. I ran stock 3.50 gears for a couple of years with a 208 transfer case and won a lot of races with it but don't try that with bigger than 35 in tires and always run low range. exhaust if rules allow run vertical exit headers through the hood.
Dang I didn't mean to write a book, but with that bieng said best bet on engine stroker big block with lots of hp, nitrous, and other adders like alum heads, and then of coarse cut boggers

 

This really is a good summary for the old "wide vs. skinny" debate. In the real world or at the bogs there often isn't a bottem to dig down to (ergo, 44" boggers rule), but for the mud drags the smaller skinny tires are where its at.

 

What's the difference beetween mud bogs and mud drags?

 

abouth 3ft of mud

 

And 50+ mph. Unless you're a skimmer playing puddle-jumper...
In the drags, you gotta break something pretty severe NOT to make it to the end of the track. In the bogs, the objective is simply to make it thru.

 

to further elaborate mud bogs the idea is to just get through the pit, or atleast as far as you can, in mud drags it's just like any other drag race it's a side by side (in 2 seperate mud pits ranging in length from 150 to 225ft) race in about 8-12inches of mud. first one to the finish line wins.

 

Rob, My truck better not get stuck when I go to Reasnor with you...I'll be pissed...

Just thought I'd add that.

 

Thats entirely the wrong attitude! If you didn't get stuck you didn't try hard enough