Pulling on a track compared to the road is two different things. To have a chance to run with these guys on a track you won't be able to run it on the road. You have to eliminate everything that is a drain on your engine. Everything that consumes HP. Alt,power steering pump,vacuum pump. Run an electric fan. Charge batteries and put them in the bed of the truck for a 2 wheel drive. I would not suggest an automatic because automatic transmissions take more hp to operate then a manual. You want all the available power you can get to your tires. You don't change gears while making your run. With that being said you need to run an after market button clutch, like bigtrucks use.. Stock clutches will die. Centrifugal clutches are what most pullers run. They are like a stall converter for an automatic.

You will have to run a turbo to make any power and play with those other engines.

If you aren't going to drive it on the road then lead the rear end. You don't need to buy a locker. What we do is fill the diff full of lead. It locks the spiders and side gears together. If you have to take it apart then melt it out. It will get loose after awhile but won't hurt anything. When you put your tires and wheels on point your valves stems at the same angle. When they get loose and twist you will be able to see it. Lead doesn't work on road trucks very well because it gets worked on so bad when you turn from one road to another it gets loose quick but for straight running on a track it is good.

You are going to have to play around and see what final ratio you can run. Thats going to be your engine rpm,trans gear and rear end ratio. You want to be able to play with weight from the front to the back so you can carry your front end on a two wheel drive. 4x4 everything goes to the front. There is allot to it and perfectly legal secrets that guys won't let out. I came up with a gearing scheme for a specific model of transmission that I won't tell. Perfectly legal because there are no after market cut gears in it.

It depends how far you want to go and people really need to be able to be to fab things their self.

 

Honestly, other than routine maintenance? Nothing.
Wobbly/loose D50, and a 10.25 running 3.55's. Haven't touched the IP/injectors.
The E40D can be your best friend or your worst nightmare, the roads out here are nothing but hills. I couldn't get the damn thing to go faster than 75 mph for months. Then after a bad, bad, BAD, AWFUL batch of diesel that had me stalling on the side of the road. I flushed her with Power Service's "Diesel 911", and just sat in the truck for like 20 min in neutral foot to the floor, and she's been purring like a kitten, better than she ever did as long as I've owned her. Once you get the shift points down, you can run her like a manual tranny, and shift when you want it to. I plan on getting my E40D beefed up in a month or two.
The engine was rebuilt 180k ago, so it's possible they worked it a bit in the shop, but thats PO stuff.
I've heard good things about the stock ford LS, if you don't offroad with it. But if your going to abuse your truck ARB, or Detroit seems to be the way to go.
My goal is to get my rear rebuilt with 4.10's, and a detroit, and run the same in a D60 up front.

Well obviously a 2WD will rarely outpull a 4WD truck that has all wheels spinning. I don't thing that was the point of the thread at all. I've pulled against 2WD trucks, who cares if I have 4wd or not, I pull in 2.

 

Not true. Have seen it to many times.

 

Well, they're accurate if not goofy facts. Good for a laugh.
Okay, so two trucks lets say both are identical and one in 2wd, one in 4WD.
That'll be a hard row unless you can adjust the hitch on the 2wd truck to do two things. 1, get all the weight of the truck on the rear wheels. 2, pick up as much weight from the sled as possible.

If you can't tweak the hitch the 4x4 will pull further. If you can you can get not only that say 3000 pounds from the front axle onto the rear tires and pick up another maybe 6000 in downforce from the hitch.

Watching the 4x4 class pull, there doesn't seem to be a lot of front wheel engagement on the ground unless they have the big stack of weight plates.

But same for same, yeah, loosing the front axle will reduce pulling.

 

I was talking about a redneck tug'o'war.

It happens, but it's a uphill battle for the 2WD guy.