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#65188 09/01/2006 1:49 PM | Joined: May 2005 Posts: 11 Junior Member | | Junior Member Joined: May 2005 Posts: 11 | A friend gave me a '56 1/2 ton.
It has a V8 in it which I'm guessing is not original, although I could be incorrect about that.
Outwardly the engine appears to be a Pontiac V8, but it wears GMC decals on the valve covers, which appear to be genuine. Also the engine has early style pre smog crankcase breather system, a cannister type oil filter and a small 2 bbl carb, so it's clearly an old engine. In addition to that the engine mounts appear to be un modified factory mounts.
So it looks like original, but I didn't think that V8s came out in GMCs til later.
Any info on this engine?
Thank you | | |
#65189 09/01/2006 2:02 PM | Joined: Jul 2002 Posts: 165 'Bolter | | 'Bolter Joined: Jul 2002 Posts: 165 | Pontiac V-8's where original equipment in 1955-56 GMC. had one many years ago. | | |
#65190 09/01/2006 2:04 PM | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | and v8's started in 55, both GMC and Chevy
Bill | | |
#65191 09/01/2006 2:08 PM | Joined: Mar 2006 Posts: 319 Shop Shark | | Shop Shark Joined: Mar 2006 Posts: 319 | This should get you started. Dave is a Stovebolt member and this is his page. Lots of info on the 55-59 GMC trucks. I'm sure others will join in. http://www.1955gmc.com/
"Nothing astonishes men so much as common sense and plain dealing." - Ralph Waldo Emerson
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#65192 09/01/2006 2:14 PM | Joined: May 2005 Posts: 11 Junior Member | | Junior Member Joined: May 2005 Posts: 11 | Thanks for the prompt replys.
That settles that. It's an original V8 then. | | |
#65193 09/01/2006 7:58 PM | Joined: Apr 2005 Posts: 1,971 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 1,971 | I have a 1959 with a 336 Pontiac motor. | | |
#65194 09/01/2006 8:09 PM | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | Because the GMC motor and Pontiac motors share so many similarities and parts, it is possible to get those pontiac hop up parts on a GMC engine. I believe you could put a Pontiac 347 tripower on that 55-59 GMC 288, 347, 336... I know I am missing one... engines, with very little modifiction. Almost a bolt on instalation. | | |
#65195 09/02/2006 4:32 AM | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | The '56 was a 316. And yas, the Poncho parts will swap.
Bill Burmeister
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#65196 09/02/2006 7:23 AM | Joined: Apr 2005 Posts: 926 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 926 | There was also a 370,just before the 389 came outin 1960 (?). Pontiac/GMC V-8 parts interchangability was good from 1955-1963,when Pontiac changed to the current BOP bellhousing pattern.(1964 was,I believe,the only year using the new bellhousing pattern with the early style bellhousing mounted starter-in '65 the starter was mounted to the block,as it has been since.)Early style flywheels must be used with early pattern bellhousings,BOP bellhousings can use BOP flywheels. (BTW-a GM 12" clutch will fit in place of the GMC V-8 11".) Front engine mount for GMC will swap to all Pontiac V-8's,as will the GMC V-8 exhaust manifolds.Same with fuel pumps,distributors,cams/lifters,timing sets,valve covers,oil pans. Okay-shutting up now...
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