The Stovebolt Site Forums The Shop Area The HiPo Shop 1957 GMC Big Window (454 Chevy or 455 Buick Motor)????

Hey Guys,
Wanted to get an opinion on something. Would a 1957 GMC truck be less valuable if it had a 1970 Buick 455 motor in it versus a 454 Chevy. It currently has a 350 Chevy in it, but I've been tossing this other idea around in my head. Just want to know what the majority consensus is. Is it more advisable to keep Chevy/GMC together? Do guys hate it when other brand motors get put in different cars/trucks. Just curious because I don't want to ruin or bring down the value of my truck. Thanks.

To a GMC purist it has already been devalued by the 350. A Pontiac would be correct for it.

If you are building it to sell I don't think there would be much difference between the 454 and 455. But the 455 would be way cooler.

1957 GM trucks actually could come with a buick motor.
The swap though is more than a motor swap. 455 is big on top. head space is wide. Does your truck have power steering? How is the 350 mounted? What tranny is that bolted to?
Going bop is awesome. I love it. Just remember BOP ain't easy.
As far as value , it is all ready been modified with a 350 in it. I think it would be worth more w 455 than 350, but about the same for 454 vs 455 . Keep in mind the 455 is lighter than 454. like 60lbs or so.
Market lately leans towards hot rods with updated brakes and steering.

The 454 will be much cheaper to play with, and easier to work with for more power.

I some what agree with Woodswarrior there. The 454 is easier to make power cheaper because there is a bigger aftermarket for 454. But a well built relatively stock 455 will produce more torque than a compared 454.
Problems come because of BOP bellhousing. auto vrs 4 speed manual. Pilot bushings and crank mods can be tricky for 4 speed conversion.
It may not be easy but its not hard either. Just takes time and searching and making sure you get the right parts for the swap.

I'd like to see some documentation of GMCs delivered with Buick engines. Some heavy duty (2 ton and up)'55-59 Chevies came with Buick engines and some heavy duty '55-59 GMCs came with Olds engines.

I'm assuming the OP has a pick up and not a big truck. It would have come with either a 270 6 or 347 8 of Pontiac lineage.

Worth has nothing to do with this equation. The truck is only worth what someone is willing to pay at the time of sale. If the truck is running it will likely be worth more than if it is not. You will probably NOT recoup the cost of replacing an engine upon sale of the truck.

However, what you prefer does have bearing. I will be getting a mildly built 1960 pontiac 389 back from the machine shop in a couple of weeks. This engine is built for 400+ hp with a stroker crank. It will bolt in where the original gmc 336 was, and look almost identicle to the original gmc motor. This motor has cost around $4500 to build. My truck looks like it is worth less than $2000. This combination is worth more to me than others because I am the one who will be benefiting from the increased hp. The "ratty" looking rusty truck does not garner a whole lot of attention or interest from most sane folk. I am not sane!

Chevy's did sorry about that. I forgot we were talking GMC. But B.O.P. is common in all trucks '55-'59 .

My personal opinion is these trucks worth are measured in smiles per mile.

I must agree there. I have more invested in mine than they are worth. But the privilege of driving them is priceless.

The 322 Buick engine was only available from Chevrolet in the 1956/57 9000 & 10000 Series 2-1/2 ton trucks and in the 1958/59 2-1/2 ton School Bus Chassis, it was never offered in any of the smaller trucks.

Mike B