The Stovebolt Site Forums The Shop Area Engine Shop 454 in an AD

Hey everyone, I was thinking about swapping my old 216 for a 454 BBC and turbo 400 trans in my 48 3/4 ton. What will I have to do to my rear end to make this work; do I need a new drive shaft? Will the stock gears in the rear end work okay?
Also is there anyone out there that makes engine-trans mounts for this set up? Will I have trouble with my steering clearance?
What’s everyone’s general opinion on this swap? Would you do it? Is it hard to do?

This truck is a work truck for a woodworking/cabinet business, but I don’t actually use it that often so gas consumption is not a huge issue. I also want to be pinned to the seat every now and again when I step on it.

Find a '64-'72 3/4-ton with the 4.11 rear end, and swap that center section into your axle. I doubt that you're going to blow up an Eaton HOxx axle, unless you're going to put a huge supercharger on that 454. As far as I know, all AD 3/4 and 1-ton trucks had open drivelines.

For more on the gearing change, there is another thread active right now talking about it.

I put a 454 in my 49 suburban with Nova clip. Exhaust clearance is a gritch...Also box and stiffen frame as 454 will make it look like a pretzel if you have a heavy foot.

49 bourbon, did you use the stock exhaust manifolds? Would block huggers be any better do you think?

I was think I should change out my rear gears, but wanted to get opinions on it. I don’t drive on the highway at all with the truck, if I need to go far I take my daily drivers.

Gecko I used hooker headers and 10 bolt rearend from the Nova. Problem is the nova is "rear" steering so steering box was in way of headers & had to rebuild two front cylinder tubes on driver side. Knowing what I know now if you go to a clip find one with all sterring components in front of axle.

As far as rear steer/front steer, 68 thru 74 Novas are rear steer, while 75-79 Novas are front steer...and came with disk brakes standard. I dunno if there's a width issue or not, but I don't hear of too many people using the later "disco" era Nova front clips. It seems like those and 2nd gen (70-81) Camaro clips would be pretty good choices. (I think the two are pretty close in size and design.)

I started a project to use a 79 Camaro front clip on a 63 Nova...but ended up buyin a house and sellin the project off before I got too far into it. The Camaro front end is a bit wide for the Nova, but might work for a truck application.

Just a thought.

Both Nova and Camaro are a little wide in the front. '78 to '87 Monte Carlo is supposed to be the right width and is a front steer with disk brakes.

If that's the case, any A/G body of that vintage should work: El Camino, Buick Regal, Olds Cutlass...even the 78-82 Malibu. I like the G-body front end, even if they DO have a tendency to wear out the center link.

I can't put my hands on my F-body documentation, but the front track width for a 78-88 A/G body is 58.5 inches, the rear is 57.8.

The interesting thing is that the G-body is a full (perimeter) frame car, while the Nova/Camaro (X/F-body) is a unit body thing...those front clips unbolt, while the G-body would have to be cut off. I spose if you're grafting frame parts it really doesn't matter...but it just seems a little strange to me. I'm also not sure about the width of the frame/subframe rails on the 2 different models.

I dunno if that clarified anything or made it foggier.

All great replies, but I was hoping to use the stock front end, I know its weird, but I actually really like the ride of the straight axle. It reminds me of what I'm driving. I plan to put a disc brake kit with power brakes etc, but I’m wondering if the big block with block hugger header is going to interfere with the inner fenders, or the firewall etc. I can get a motor mount for it, but will the tranny hit the bottom of the cab?
I'm pretty sure I am going to attempt this, but I just want to know if it’s going to be a weekend job or if it’s going to be a year of weekends job, and if so why?

My good friend had as his first vehicle, a 1958 Chevy truck that he put a 396 BB in. He mentioned that it was necessary to move the firewall back a few inches and make a little bit of a transmission tunnel. He welded mild steel where he had to do some cutting.
You may have to do that. Small blocks and big blocks mount the same for Chevys and use the same tranny and bellhousing. So ask over in Hipo what some of those guys had to do. You'll have to do the same.

I have heard somewhere that 67-69 Camaro headers will fit inside the frame rails of these old trucks. But I don't know if that's the case with big blocks, which are wider. You may end up having to have the headers go on the OUTSIDE of the frame rails and through the fender well.

A big block in one of these trucks would be wonderful. I'd like to use a 406 small block in mine someday. Probably bolted up to a Muncie.

(My truck is not an original survivor, BTW).

Somewhere between the two....

I say that because I don't believe there is anyway you'll get an exhaust manifold or header to fit without moving the steering.

There is a power steering kit based on using a 70's pickup power steering box. If you can first convert to power steering using a kit like that, and arrange the shaft from the steering column to the box out of the way, then I'd believe you MIGHT pull the rest of it off in a weekend. But I'd bet against you.

Length shouldn't be a problem if you are replacing the manual transmission with an automatic. I say that because it allows you to position the motor farther forward to avoid changing the firewall. If you stay with a manual transmission using the stock bellhousing location (to simplify clutch linkage) you may need to modify the firewall to fit heads and distributor, though I don't actually know that.

I've seen a big block in an AD truck so I know it can be done. One I've seen is a straight axle with a power steering conversion. The other used a Monte Carlo clip so the steering and mounting issues are completely different.

I just looked back at your initial question. The 3/4-ton uses a partial driveshaft. Unless you want ot use the original transmission you'll need a new driveshaft. Without re-reading the entire thread I don't recall if you've said what you want for a transmission.

What I was actually planning was to buy a 70's pick up with power steering and use the power steering, the engine, transmission and the rear axle from it, and have a new drive shaft made up to get the correct length. I'm hoping to get a truck with a th400 trans so it would be automatic. If I can’t find a truck with the th400, I can buy one from the scrap yard for about $400 with a warrantee. Or even a 700r4 for overdrive. I don’t plan on using the original transmission, so I was surprised to hear the need for cutting and moving the firewall.

Unless you're planning to drive it hard, any GM automatic is probably going to be fine. If you start with a 70's Chevy pickup most likely it will have a TH350.

If you run Mustang II IFS you're going to have a tough time matching the front disks bolt pattern to a 70's Chevy pickup rear. Also, the pickup rear is going to be a little on the wide side. I'd suggest looking for a 70's Chevelle or Camaro/Firbird rear. That bolt pattern will match the 5x4.75 disks you can put on the Mustang II IFS.