The Stovebolt Site Forums The Shop Area Engine Shop 1954 Chevy 3600 engine swap

I am getting a small block chevy from my grandpa and was just wondering if I would need to change the rear end. I am still debating on a saginaw 4 speed or a turbo 350 trans. I want to build the engine for torque and pulling.

Everything you mentioned would not be usable with an original torque tube driveline. So if you have the original 54 driveline then either you would modify the rearend for an open driveline or change it out.

Your truck, being a 3600 has an open driveline already, not a closed driveline.

If you're going for torque and pulling, go with a SM 420 or SM 465 transmission.

Find a side mount bellhousing from a 55 to 72 V8 truck.

You'll have to use front mount motor mounts if you use the bellhousing mount.

Like with all V8 swaps, there is the steering box clearance issue.

Depending on what transmission you use, you may have to modify the driveshaft, with the SM 420, may be a direct fit.

Right now it is a 2 piece driveshaft. there is one that goes a ways past the cab and a second one is a couple feet long that goes to the rearend. What is the price of a good SM420 trans? I think the gear ratio of the rearend is a 4.5 something if i remember correctly. Will i be able to cruise with this at all or will i even be able to tow/haul that much?

If you tell us where you are, rather than just USA, one of us might be nearby, with a 420! What is the rear gear ratio, what one thinks it is might be is far from reality, check it for sure, then make an informed decision how to proceed.

Ed

Im in central Mn. Im not going to take the diff out of my truck so ill just assume its the 4.57 gear ratio. Ive been reading and a couple of posts on other forums says the 465 has a better first gear.

Very sorry I missed the fact that it is a 3600. That makes things a little easier.

The difference in first gear ratios really isn't an issue. They're both so low it doesn't really matter. You may be a 1/2 MPH faster with the SM465. You'll probably find yourself taking off in what is 2nd more, unless you're on a steep hill.

Both trannies are tough as nails. Hauling/towing not an issue. The 465 is probably the better of the two for being heavy duty, plus it has better internals and shifting manners.

With the 4.57 rearend, you'll be turning about 3000 RPM at 60 MPH, which is about all that you'll want to do in a drum-brake straight axle truck.

BTW- The SM465 has a different front bearing retainer than the SM420. If you want to use the factory mid-mount, you'll need a 67-72 truck bellhousing with side mounts.

Thought I'd throw this in there.

Here's a couple different designs from Speedway for front engine mounts.

http://static.speedwaymotors.com/images/charts/How-EngineMounting.gif

Steel mount

Aluminum mount

Will the sm420 and sm465 be useable for low-mid speed driving or will it only be good for pulling?

2nd. gear in the 420/465 is approximately equivalent to 1st. gear in a 3 speed. It's also synchronized, which allows you to drop the trans into second on a rolling stop, which can't be done with 1st. on an early model 3 speed. Most people stay out of granny gear unless they're getting a heavy load moving or they're starting on a steep upgrade. With the 4.56, third gear should be good for any speed from 10 MPH to 30 or so.
Jerry

another question I have is what will be the easiest way to make my truck into a dually? I found some wheel adapters but those are fairly expensive. I just like the look of the dually better than the single wheel. Also what kind of rims should i look for so that the front and rear rims match? Will there be a clearance issue at all? I am going to be making it into a flatbed also.

Buy a 3800 and sell your 3600 to someone who won't butcher it up. Most of them are flatbeds already so it will save you a lot of work.
Jerry

There isn't much of it left the way it is. If i tried i could rip off both front fenders. there's a 1 foot x 1 foot section on the floor already rusted out and that's on driver and passenger side. The bed is held on by 2 bolts. It is pretty far gone.

It might be worthwhile to look for another truck out of the 'rust belt', you will be time and money ahead, much less not have to update your Tetanus shots.

Ed

im only 15 so ill probably try everything on this one and try to learn more before i buy a nice truck and butcher it. This one was also free and i can get a free engine from my grandpa. I want to try and build an engine for this truck instead of learning to build it when it actually matters.

You have the right mindset. At 15 you can learn a lot about these old hunks of iron and in a few years you will have a nice truck to show for your efforts. Soak in as much information as possible from the vast wealth of knowledge on this board. Let the snide remarks from some of the grumpy old men just roll off your back and keep on working. Good luck and have fun.

I will second this. Sounds like you have a nice project. I'm assuming you will getting some help from grandpa. Can't replace that with anything.

On making your truck a dually. Longer Wheel studs are the only thing you need on the rear. If you want the dually wheels on the front you need wheel spacers from a dually.

Do any of you guys know of any brake upgrades i can do for my truck? I have only seen disk brake kits for the 1/2 ton trucks.

another question i have is how should i setup the clutch pedal? Would it be easy to just buy a new clutch, brake, and gas pedal assembly or buy a separate clutch pedal and install it?