1955 GMC V8 question.

Thank you everyone for your replies & comments, about my 1955 second series suburban, I knew a 287/288 GMC v8 would be correct for the year, but I didn't know there were so many other engine options. I'm trying to do my truck mostly stock, I have redone the original style brakes, steering and suspension. I have 16" original wheels & I was considering and original engine only to keep it stock looking. ( a 350 SBC is probably an easier choice but I feel the truck may be worth more restored close to original) I have already an ex drag motor '59 389 bored out to 421 with a solid high lift cam, JE dome pistons huge heads and an offy 2x4 intake last ran in 63 it was apparently 13.5 to 1 compression. I dont really want to run avation fuel and i feel that engine would probably be too agressive for this project. rebuilding this particular engine in a more suitable form seems a waste as well. Which is why I wanted a 287. form your comments it sounds as though a 287 would probably mount in successfully, although I bet there would be a physical difference in the mount it self car to truck. I wonder if the oil pan is different?
some one above raised a good point about using the hydramatic as being expensive to rebuild.. any rough guess at how much? are the car and truck hydramatics different?
are the truck automatic columns hard to find? anyone have one?

further thoughts & comments appreciated.

 

bttt

 

The columns are the same for either transmission (column/box is one piece), it's the shifter assembly you need to find...they're kind of scarce.

If you could find any mid-late 50s Pontiac V8 with it's attached transmission, preferably from a running/driving car, that would probably do what you want. You should be able to figure out a way to mount it.

Finding the original truck stuff will keep you busy for a while. They're out there....saw one around 2004 in Vegas, friend of a friend had a rough long bed GMC truck with all original running gear, poncho engine and hydro.

 

bttt

 

I saw some '55 GMC pickups with the Pontiac 287 ad later model with the Pontiac 316. Pontiac felt so strongly about those engines that their factory performance unit actually introduced a cam and dual quad manifold for them. I still see the manifolds at Swap Meets. Then in '57 Pontiac used the Tri-power on their performance 347. Those were strong blocks and had good potential. The Tri-power was a Pontiac hallmark through the seventies.
Normbc9

 

I bought a restored Pontiac 287, painted red, from a guy who was restoring a 55 GMC. I know for a fact that GMC was powed by Pontiac in 1955. I'm not sure when they switched to Chevy. The oil pan for the GMC fit the car (55 Chieftain) so I would presume the two are the same. A 4-barrel carb and dual exhaust were the performance pieces for 1955.
These engines had a single saddle mount at the front of the engine and two mounts on either side at the rear of the bell housing... opposite of the SBC.
Bil

 

Anybody have any more info on the big Chev trucks that supposedly ran buick 322's? I'm looking for a less expensive (than aftermarket adapters) option for a nailhead to chev 3 spd trans....were all these trucks Hydramatics? if not is the mounting of the industrial trans similar to the car trans?

 

ive seen a few of the big trucks with the buick engines. and they had the stick transmissions. Finding one of those truck bellhousings today would likely be hard. even finding a buick stick flywheel would be difficult. ive got a offenhauser adapter that adapts the buick engine to a ford transmission.

 

I think the Buicks were used in school buses....yeah, really hard to find today.

 

In 1963 GMC began installing chevy 230,s and a few 283,s in the trucks. They still continued to use the GMC V6 engines. those V6's where heavy came in 305-351 &478 cu in and there was a V12 version also. I once owned a GMC truck tractor that had a V6 478 toro flow diesel engine. Also in 63 the GMC went back to rear leaf springs instead of coil springs and trailing arms.

 

just get some later open chamber heads & intake from a 400 . install them on the 59 engine to lower compression. the later electronic dist will fit also. and you can use the later oil filter adapter and use a spin on oil filter. My 55 287 the water pump was leaking. I looked and the water pump on my 63 Pontiac tempest 4 cyl was the exact same right down to the casting number. I looked on E Bay and found a NOS water pump for $5.00 plus shipping. The same type pump listed under the v8 was about $100.00

 

Yes I neglected to mention the 401 likely because that's the only V6 GMC engine that I never owned.

 

[QUOTE="Old wolf ]ive seen a few of the big trucks with the buick engines. and they had the stick transmissions. Finding one of those truck bellhousings today would likely be hard. even finding a buick stick flywheel would be difficult. "
I worked on a few of the BIG Chev trucks with Buick power. The flywheel/clutch setup was 12'' or 14'', and the bellhousing is not a hot rod item ... If someone finds an intact truck, however, many were 5 speeds, a very desireable restorer part. If 5th OD, you can name your own price ... same info applies to GMC of that age group.

 

My friend had an original 56 with a Pontiac motor and hydramatic. To my knowledge all those hydros mounted at a bell housing area. In fact I have some of those mounts somewhere in my junk nos. I don't know what they fit. Buick, Pontiac, Olds or maybe even 55-57 Chevy they are all similar.

Pat

 

I don't know if the original poster - from SIX years ago - said yet, but if the GMC was Canadian-built, it wouldn't have come with a Pontiac engine anyways. 261 or 265. No 270 or Pontiac motor....If he was doing a 100% nut and bolt resto and the truck was Canadian built, the Poncho engine isn't correct...