[uneasyrider]

I have a line on some old GMC PU's at an old junk yard up here that still have engines. How do I tell if it has a 370 and for that matter how I would know a 370 if I saw one someplace else?

Thanks,

[hellerods]

I can't help much- 370's look simalar to all pontiac v8's , I think that the biggest most noticeable visual difference is the water outlets that come off the front of each head. If I remember correctly ?? I'll look for a picture I took of 32 or 33 three window ford with a 370/dual quad hot rod at Pismo's car show this spring. If you send me your e-mail ,I'll send you a cool engine pic. Lee

[poison heart]

If it's a '58 it's a 370. If it's a 55-59 they have water outlets in the heads. How to tell all the early motors apart I'm not sure. I think the 55 and 56 had the Strato Cheif emblem on the valve covers.

[johnta1]

The block will have a block casting code of 528456.
The date code will probably be useful, also.

Engine Codes

The block code would probably be the best bet, though, used on only the 370 engines.

[Bill Eveland]

The GMC will have a small bore 336 for 58/59 not 370/389 like the cars.

[Jack Gifford]

Originally Posted by Bill Eveland

The GMC will have a small bore 336 for 58/59 not 370/389 like the cars.

Correct. 370 was never used in GMC.

[uneasyrider]

Thanks for the info guys! Everyone on here is so full of it... info that is. I was also under the assumtion that the GMC must also have the same cid as the same year Poncho but I see that isn't correct.

Cool picture hellerods! I see what you mean about the water pump.

I've got some more engine questions I'll tack on to another post I had going on "287 overbore" in the Street Forum.

[Safari Larry]

For info on how to identify Pontiac engine and engine components, see www.pontiacsafari.com/L1Garage/EngineID. For info on Pontiac engines, including the GMC, see http://www.pontiacsafari.com/L1Early...s/V8%20Engines.

Bill Hanlon (GMC Bill) helped with both those articles and I haven't seen him post here lately. He lives in Houston so I hope he survived the hurricane OK.

[Bill Hanlon]

Originally Posted by Safari Larry

Bill Hanlon (GMC Bill) helped with both those articles and I haven't seen him post here lately. He lives in Houston so I hope he survived the hurricane OK.

I'm here, just no power at the house yet. Very minor damage and the backyard pool looks like guacamole.

[Jack Gifford]

Originally Posted by uneasyrider

... I was also under the assumtion that the GMC must also have the same cid as the same year Poncho but I see that isn't correct...

That IS CORRECT for 2nd-series-'55 up through '57 GMC (287/316/347 engines). The only GMC difference was lower compression. And I think a different 2-bbl carburetor- Bill Hanlon probably knows about the carbs.

[poison heart]

Sorry, I thought the GMCs had the same cube pontiac motors except '59. I have a '59 336 in my garage as a spare. I thought it was a 389 until a few months ago.

[Old Goat Racer]

No engine mount holes on the side of the block.

[hellerods]

here is a pic I think

[uneasyrider]

Thanks for the info Larry.

[poison heart]

I know my 59 GMC motor has a different carburetor on it. The Pontiacs had the Rochesters. Could it be a Stromberg on the GMC? I can't remember what it is but it has the smaller bolt pattern and a carb adapter to adapt the Pontiac manifold to the smaller carb bolt pattern. This is the only picture I can find. The middle carb is the one from the '59 GMC and the front and rear carbs are '59 Pontiac Rochesters.



Wait here's a better one


And here's a picture of the manifold off the GMC motor.


GMC


Pontiac

[Bill Hanlon]

Originally Posted by poison heart

I know my 59 GMC motor has a different carburetor on it. The Pontiacs had the Rochesters. Could it be a Stromberg on the GMC?

The GMC trucks used a Bendix/Stromberg WW carb. Most were manual choke, but a few (mostly Subrubans) were auto choke.

[uneasyrider]

Good pictures.

Thanks,

[poison heart]

Thanks for clearing that up. I'm glad you're OK from the storm

[Steve Barcak]

I wouldn't mind having a few more 336s either '58s or '59s. If anyone has some closeby, or can hang on to them. Let me know.

thanks, Steve

[poison heart]

I'd trade you for a '59 389.