The Stovebolt Site Forums The Parking Lot Big Bolts engine swap

Hi I'm new i bought a '47 Chevy 6400 i was wondering if anybody has ever swapped a big block 454 into one of these trucks and what did you have to do to make it fit

Try a search in the Big Bolt area for 454. I just did & got two pages of 454 talk! :blat:

It will be tight...
Why do you want a 454?
What will you do with the truck?

What about a diesel, perhaps a 4-53... only one digit off?

Grigg

There are a number of issues you'll need to deal with. A 454 makes a lot of heat, and you'll need a plan for dealing with that. Most small block swaps seem to work fine using a stock radiator. With the big block it may require something more to keep it cool.

Steering clearance is the most difficult problem. The steering box and column will interfere with the exhaust manifold. With a small block swap you can shift the motor to the passenger side, and move the steering box a little to the outside, and make it work.

With the width of the big block those options are not gong to solve the problem. On a 1/2-ton truck a power steering kit that moves the steering box ahead of the axle would solve the problem. On a 6400 the common kits would be close but not quite right.

Grigg's question is a good one. Why do you want to go 454? He may be challenging the choice, and he is a fan of the Diesel solutions. But you will encounter enough hurdles that knowing why you are doing it will be important to keeping motivated to solve the problems.

And knowing why you want to make the swap also helps when it comes time to decide how to solve the engineering problems involved. If you want to use the truck as a truck you'll make different choices than if you are building a cruiser using a big truck.

For instance your transmission choice depends on your intended usage. Choosing manual or automatic affects several issues, including engine placement, which of course affects engine mounting...

I have to admit that I'm also building a 454 powered truck. I'm starting with a 1-ton, though I've considered using a larger truck frame. My goal is to replace my modern trailer puller with a classic. I like the sound and performance of the big gas motor, and don't care for the noise and smell of Diesel.

I'm using pieces from a 454 powered 1-ton pickup (recently wrecked) and a 454 powered motorhome with a Turbo 475 automatic. I'm still debating some of the design elements, but think I have all the big parts on hand already. My remaining decision is whether to stay with the straight axle or convert to an IFS. I change my mind every other week, and probably won't start in earnest until I've settled that issue.

Do try the search feature. You'll find some of your questions answered, and probably find some ideas that will lead to new questions. And who knows, maybe Grigg will persuade you to consider Diesel power instead...

I may have a little more room than you with your 47 but I am putting a BB in a 56 you may wish to spend some time in my web shots page.

BTW Steve another good reason for you to come down

i was planning on using the 454 because i had it and a TH400 transmission that are both rebuilt out of a '76 1/2 ton.
i do like diesels but i am 14 so i don't have a hole lot of money to spend for the engine and trans. anybody know about how much a used 4-53 and tranny to go with it will cost?
steering wont be too much of a problem because i want to do a axle swap something like what grigg did.
i will mostly use it for pulling a trailer and going into town every once in a while.

also has anyone tried to do a disk brake conversion on the original 2 speed axle?

You don't want to do a disk brake conversion on the original rear axle. The rear gears even with that 454 are going to limit your top speed and there are no good options for that axle. Better to swap another rear under it, and best would be to find something that already has disks if that is your preference.

You may want to look hard at Grigg's photos of that axle swap and get a good description from him of what it cost. Doing a swap like he did doesn't mean the steering won't be a problem, it just means you have a different set of problems to tackle. But doing one the same as someone else has does mean you can ask questions about how to procede.

What kind of trailer are you planning to pull, with what kind of loads? Where do you plan to pull that trailer? What do you plan to haul on the bed of the truck? I ask because it will be easier to make suggestions and answer questions with that kind of context. Do you intend to preserve the 16,000 GVWR?

If you are 14 I assume you are at least a year away from being able to drive the truck on public roadways. That gives you some time to work on doing it right.

i am planning to pull a flatbed car hauler most of the time, usually with cars but i will probably be picking up supplies for my dads business. i live on the top of a hill so it has to be able to go up the hill with a load. th e truck doesn't have a bed on it now i was planing on putting a fifth wheel on it to pull a camper trailer. i will probably exceed the 16000 GVWR. also how am i supposed to ask grigg what the 4-53 and trans cost.

454 is not a good truck motor.
They do not make torq.
They are an RPM motor; meaning as long as you keep the RPM's up they will pull. Trucks prefer to operate at lower RPM's.
The auto trans will help hide this flaw. But still when you get in a bind, it will take loads of throttle to get it moving.
And will be a fuel pig.
The 402 was a torq motor. but is balanced opposite the 454.
One is internal balanced the other is external.
Anyway you need to break out the vintage truck manual and see what motors were used in trucks. 366 and such that make big torq at lower RPM's.
Well that is what i know about that.

Price on a used but good running 4-53T (from a very late 70's GMC truck probably the best place to start) seems to be around $2,000. I would imagine anyone selling one would include the 5 speed Spicer in the same price, because they are not worth much and most all are not OD. You will need OD to make it a useful truck with a diesel. My local junk yard just got one of these trucks in with a good engine, and for sale, PM me for the contact info.

OD trans options are out there, anything with a SAE#2 bell-housing, but expect to pay up to or about $1000 for a good used modern 6 or 7 speed OD, more for a small Roadranger 10 speed OD.
A used Spicer 3053A from a deuce and a half has a 0.80 OD (or is it 0.84?) they can be had from around $50 to $250 good used or government rebuilt.

If you do the axle and steering swap, Detroit 4-53T, and OD transmission, I can't begin to to guess at what it all cost for you to do right.. Although I have found excellent deals and prices on all the parts and components I need for my project, at the expense of time to research, wait for the right deal, and find the best prices, I still have a frightening amount of money in my project, and there is lots more to do.

I initially questioned you about your engine choice and suggested the 4-53, not so much because I think it is the best swap, but just to get you thinking and to explain yourself. A 4-53T, while I really like it, is not an easy swap into an AD truck. Even cutting corners, doing a half asked job, and finding everything in the junkyard, it will take lots of time, some money, and determination.
I much prefer the do it all right the first time method, even with the up front cost.

It has been said that "If you can't afford to do it right the first time, then you can't afford to do it over"

Grigg

If you plan to stay with a gas engine, the older GM school busses look like they could be a pretty good donor vehicle and they seem to sell cheap. I don't know if any of them ran the 4-53T.

After I finished my 2 ton which won't be heavily loaded, I learned that a P-30 which could be bought for less than I spent on my engine alone, would have been a good donor.

I can understand wanting to run the 454 and turbo 400 you have. Making that choice you are accepting the limitations of that combination.

If you look around you'll find 1-ton pickups, weighing about the same as your 6400, pulling 5th wheel trailers, and running the 454/turbo 400. Talk to the people using them to get a sense of how well they do. These will be older trucks because most now have an overdrive automatic like the 4L80e.

Using a 6000 pound 454 powered pickup to pull a loaded flat bed car hauler weighing 7500 pounds I was able to exceed the freeway speed limit, and climb my own steep driveway. (I say was because that truck was totaled in November.) Remember the 6400 moved the load with a 235, but did not do so at speed.

You've defined more of what you intend to do. I'd suggest thinking in terms of axles both front and rear from trucks that weigh at least 6000 pounds and are rated to pull the 5th wheel trailer. Choose a rear axle ratio used in a big gas powered Chevy or GMC pickup designed to pull a 5th wheel.

Most of what you are trying to do has been done by General Motors. Look at their solutions and ask users if they are satisfied with how they work. Then copy the ones you like best.