Engine Decode

ukc10

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Hello from the U.K. I have just imported a '71 C10 350 from VA.
Any help to identify the engine would be appreciated. The front pad 1st. line is stamped V0314 UPY however I can only find reference to URY. The 2nd. line looks to be hand engraved CG 4150389.
Regards Richard.
 

ChevyHiPro

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Hello and welcome to the forum!
The number you've posted is the Engine Assembly Code, it should tell us a lot about your engine.
So, let's attempt to decode it;
V0314 UPY - V = Flint, MI (vehicle assembly plant), 0314, March 14 (date code), UPY (Engine Suffix Code) - UP = 1969, 307 CID, 200 HP, 2 BBL, M/t (tranmission).
I looked at a number of sources and only was able to find the Engine Suffix Code UP.
I couldn't find the Code UPY, it doesn't show up.
The 307 CID is a 5 liter engine.

The other number you've posted, CG 4150389, appears to be the Engine Partial VIN Code, however, the format is not proper for a 1972 or later engine.
The engine coding format was standardized by government law beginning with the 1972 model year.
Part way through the 1971 model year production GM required all it's assembly plants to implement the new law, so the bugs coul dbe worked out and the entire corporation would be up and running in full compliance as the 1972 model production began.
So, it is very reasonable a 1969 manufactured engine would have an unusual Engine Partial VIN COde format and not readily decodeable by modern information.

Lastly, these Engine Suffix Codes have not been released by GM to the general public.
The listings online have come from many individuals recording information as they pulled engines from original cars and such to compile the information bases we now use to 'decode' these engine numbers.

I hope some of this information is useful to you.
 

ukc10

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Thanks for the info. I did try to research the E.A.C. UPY myself and only came up with UP or URY this engine is supposed to be a 350. Is there any other way to tell the difference between a 307 and a 350?
Regards
Richard.
 

ChevyHiPro

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Yep, there are several.
The most inconvenient is to measure the engine bore and stroke!
307 = 3.875" bore x 3.25" stroke" , 350 = 4.000" bore" x 3.48" stroke"
Of course, this means pulling the intake and one head.
Not really practical for a running engine in a vehicle.

So, another method is to try and find the displacement casting mark.
These will be 5.0L (307 CID), or 5.7L (350 CID) raised, cast numbers and letters that normally appear in the area just in front of the large, semi-circular 'flange' where the transmission bolts to the engine, normally on the drivers side and it could be high up the block, possibly behind the drivers side head, or even on the passenger side of the block.
On the passenger side, you have the starter, that may obscure the casting mark.
It will take some patience, a good flashlight and maybe a mirror.

Good luck with your '71 pickup!
With the cost of gas in your part of the globe, I hope you can afford to drive it some!
:-/
 

ukc10

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Thanks I will have a look at the weekend. Its just as well we are used to the high price of gas as at the moment it is £1.40 per litre! which is approx $7.9 per US gallon so yes it can be an expensive hobby. But I have owned various U.S. cars over the last 30 years and you just get used to it.
 

ukc10

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Hi, other than the casting no. on the passenger side, these are the only other markings i can find on the back of the block.

Looks like GM 5.? L G
What do you think?



Thanks
 

ukc10

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Looks like my son might have solved it!

We have casting number - 14088548
Which Chevymania.com kicks out as - 350 '86-88, 155-195hp, 2-bolt, Truck Passenger, stick 1-piece seal

And UPJ - '86, 350ci, Truck, 160hp, LT-9, 4-Brl, C-20 & C-30

Thanks for your help, Richard
 

ChevyHiPro

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Well, with the casting number, that helps narrow it down.
I checked a couple of other sites and your son's info is spot on!
Well done!

Now, here's an additional little bit of info, '86 was the first year of the roller cam small block!
From the casting number, your engine is a truck engine, so will have a roller cam (and will accept any SBC roller cam, GM or aftermarket), however the lifters will be regular hydraulic flat tappet as will the remander of the valve train.
Some of the early roller cam SBC's had 'bosses' cast on the cam tunnel, that can be drilled and tapped to hold the 'lifter tray', that keeps the roller lifters straight.
A search for a 'how to' will yield a number of results.
So, with the block stripped down, it can be modified to a full roller valve train.
Chevy has a number of strong GM roller cams that can be had (used condition) through wrecking yards for cheap.
Well, leastwise on this side of the pond.
That block can build a very large amount of HP and torque, for cheap.
Chevy has several series of factory heads that flow very well.

You mention gas is £1.40 per litre in your area.
I am planning a holiday either late this summer or late next summer, to the Isle of Man.
I live in south central Texas, so it's going to be quite a trip.
I would love to go for the motorcycle races, but don't enjoy the massive crowds and jammed accomodations, so we'll be going after the races, probably in August.
I found an agency (Manx Mini Adventures see link below) on the Isle, that hires classic MInis for £70 per day between May and September, £60 per day from October to April, of course + applicable taxes.
Then I did a search for gas prices on the Isle, looks like £1.55(IMP) per litre!
So, I guess I'll be bring my petrol with me from Liverpool on the ferry!
Save 15 pense per litre!
:)

http://www.visitisleofman.com/thingstos ... ntures.xml

Keep us posted on the progress with your roller cam 350 vintage pickup!
 

ukc10

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The good news is that the Mini should average 35+ mpg.
Truck passed inspection Monday so we are now on the road and ready for the shows.
I have family in Virginia Beach and have visited a few Eastern/Southern states but not Texas. My son and I are looking at going to Scottsdale auctions next year which should be good.
Enjoy your holiday.
 

ChevyHiPro

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Glad to hear the truck passed your UK inspections and you can legally drive it on the roads now.
Let us know how you make out in the Shows.
Post some pictures of your truck at the shows, we'd love to see them!
Arizona is a great place, awesome scenery!
If you go in the summer, take plenty of sun screen and light clothes!
Enjoy!
 

J.tiner

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Can anyone help me with the numbers I found on a 350 I bought? numbers below the head is 3970010 and numbers in front of the passenger head are v05021yz0 and another set of numbers c5f162038 numbers on drivers head under valve covers are 333882...can anyone help?
 

Casey

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I’m trying to figure out what type of motor I have. I have a 79 Chevy Silverado it originally had a diesel but it was changed out by the dealership I have a number off the intake that is 22508087 *D2D and a number off the front of the block that is 3161 GM 501G. It has something on the back passenger side of the block but I can’t make it out. Any help would be appreciated. Thanks
 

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