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#37300 05/21/2005 9:19 PM | Joined: May 2005 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 41 | A little help please! I'm having trouble identifying the straight six in my '52 GMC 2 ton. I had thought that most of these were a 270, but this apparent military surplus has a tag in the glove box saying it is 302. Could this be a mil-spec bored out 270? This seems to be a rare 2 ton. It has HD 10 bolt hubs/axles that should have been only on class 8 Cannonballs for this year. The cab and hood are not the stretched version used on class 8 conventionals, but the same as 1 1/2 tonners on down.
Terry Wofford
Terry Wofford
'52 GMC 3 1/2 Ton
'51 GMC 2 1/2 Ton
'53 GMC 1 1/2 Ton
'53 Chevy 2Ton
"If it ain't broke, well give me the keys and I'll be right back!"
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#37301 05/22/2005 3:43 AM | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Is there a serial number on the motor? Stamped on a machined pad near the distributor? If so, the first three numbers should be the motor size.
Aside from that, casting numbers are your best bet. On my 270 the numbers are below and behind the exhaust manifold. inliners.org has information to sort out what casting you have.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | |
#37302 05/22/2005 11:17 AM | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | If it's a 302 then you are a BIG winner! | | |
#37303 05/22/2005 2:02 PM | Joined: Jan 2000 Posts: 1,586 Extreme Gabster | | Extreme Gabster Joined: Jan 2000 Posts: 1,586 | On the machined distributer mounting pad is the engine size,first three numbers indicate engine displacement. | | |
#37304 05/23/2005 9:13 PM | Joined: May 2005 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 41 | Originally posted by 53moneypit:
If it's a 302 then you are a BIG winner! So a 302 L6 was a legitimate engine size?
Terry Wofford
'52 GMC 3 1/2 Ton
'51 GMC 2 1/2 Ton
'53 GMC 1 1/2 Ton
'53 Chevy 2Ton
"If it ain't broke, well give me the keys and I'll be right back!"
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#37305 05/24/2005 1:21 PM | Joined: Jan 2005 Posts: 310 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 310 | Yep. The 302 was the biggest of the "small" GMC 6's. Quite popular with the hot rodders of the 50's.
-Tim
'51 Chevy 3104 w/'56 235, 848 Head, HEI Dizzy, Corvette Cam, Split Manifold and Dual Carter YF's
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#37306 05/25/2005 4:40 PM | Joined: May 2005 Posts: 41 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 41 | Thanks to all for the info. I found the stamping after wire brushing some paint off, it must have been painted after a rebuild sometime. It is a 302! Now the problem is finding any parts or information on it. Nobody around hear has even heard of it. Is there any books out there that would help? What I need to know is if some parts or gaskets are the same as another common L6?
Terry
Terry Wofford
'52 GMC 3 1/2 Ton
'51 GMC 2 1/2 Ton
'53 GMC 1 1/2 Ton
'53 Chevy 2Ton
"If it ain't broke, well give me the keys and I'll be right back!"
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#37307 05/25/2005 5:07 PM | Joined: Jan 2005 Posts: 310 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 310 | Patricks will have rebuild and performance parts. They have a nice catalog, and have been working with GM 6's for many years. Check them out at Patricks
-Tim
'51 Chevy 3104 w/'56 235, 848 Head, HEI Dizzy, Corvette Cam, Split Manifold and Dual Carter YF's
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#37308 05/26/2005 4:04 AM | Joined: Mar 2004 Posts: 83 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 83 | Olson's Gaskets should be able to set you up with a set of gaskets. They are located in Port Orchard, WA. http://www.olsonsgaskets.com/ Good Luck, Garry K
Garry K in Pac Nor West
1948 Chevy PU 235 SM420 4 spd
1932 **** B pu
1964 Datsun 4x4 with SBC, SM465 4spd and Rockwell xfer Dana 44Fr and 12 Bolt Rr.
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