350 or 327?

bad86camaro

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i recently bought an 84 camaro with what i was told had a rebuilt 350. comming to look at the numbers im not sure the casting number on the back says 307 327 and 350 all 4inch bore but i cant decode the serial number on the front(17B478815). im possitive thats not origional but just fine. if anyone can help i will be gratefull.
 

ChevyHiPro

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Hello and welcome to the forum!
The number you posted, 17B478815, is the Engine Partial VIN Code.
That is assuming you found it on a raised pad at the passenger front on the block, just below where the head sits.
If so and if this number is a hand stamped number, it is in fact the Engine Partial VIN Code.
It will tell us a little about the engine, but not much.
There should be a second number stamped on the same pad, that will be the Engine Assembly Code.
That number will tell us a lot about the engine.
That area of the engine gets really caked up with paint, grease and dirt that obscures the numbers.
A good cleaning with a rag and solvent, then possibly cleaning with a wire brush will show all the numbers.

Now to your Partial Engine VIN Code;
17B478815 = 1 = Chevy, 7 = 1977 or 1987 (model year see below), B = Baltimore (vehicle assemble plant), 478815 = Partial VIN Number (last 6 digits of the vehicle VIN number).

The model year is difficult to determine without the Block Casting Number or the Engine Assembly Code.
If the engine is mounted in a car and running, the Engine Assembly Code is the easiest to get to.
As mentioned above, the Engine Assembly Code is hand stamped on a raised pad, located at the passenger front of the block, just below where the head sits on the block.
This is usually behind the alternator.
Once exposed, the area needs to be cleaned with a rag and solvent, then possibly a wire brush to fully expose the numbers.

If you could clean the area and find the Engine Assembly Code then post it in this thread, I'll do my best to help you figure out what your engine is.

I hope some of this helps!
 

bad86camaro

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all i found on the pad is 17B478815 29KH and on the back for the casting number is gm 3970010 i know gm used the same casting numbers for diffrent years but this eludes me. i appriciate your help thanks.
 

ChevyHiPro

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Now we got a little something to work with.
3970010 - Block Casting Number - 1969-1979, 302 CID/350 CID, car & Truck 2 & 4-Bolt Main, 4 Bolt Most common
This is one of the most common block casting numbers Chevy used.

This number, 29KH, appears to be a part of the Engine Assembly Code.
The most information form this code comes from the Engine Suffix Code, the letters at the end of the number.
KE - 1966, 327 CID, 350 HP, 4 BBL, m/t 4 spd, s h/p, A.I.R., a/c, vette

So, from this Engine Suffix Code, seems this engine started out life as a 327 CID, 275 HP Vette engine.
A 350 block can easily be made into a 327, the bore is the same size 4.000", the storke is the difference.
So, with a different crankshaft and connecting rods, it becomes a 327.
Or, vise-versa, change the crank and rods and the 327 becomes a 350.
We do that regularly by putting a 400 crank in a 350 block to make a 377 CID., then bore it 0.040" and it becomes a 383.

So, in reality, to find out exactly what the displacement of your engine is, it would be necessary to pull a head, then measure the bore and stroke, that will tell you what the real world displacement is.

There is a bore and stroke chart near the top of the Engine and Parts Identification Page, the listing is called SMALL BLOCK CHEVY BORE AND STROKE.

I'm pretty excited that you probably have a '66 vette 327, 350 HP engine!
 

bad86camaro

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yea me too i bought the 84 z28 because it had a bad trans and i made my money back well fold just with the dash pad alone. it had not one scratch or crack on it. plus this engine was in it with plenty of new parts which i needed for my 86 since im in the middle of trying to restore it. i got my 86 all stock when i was 16 and well... its had a hard life you know ha ha ha and now im paying for my foolishness but shes getting there and thanks again when i rip this engine apart ill let you know what i come upon.
 

ChevyHiPro

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One last thing, these older engine code (before 1972) did not follow a consistent code format,
We have the records from 1972 and up to try and decode the older engines, that's not an exact science.
But, the engine is what it is.
With a head off, all the mystery disappears!
Measure the bore & stroke and it is what it is!
As mentioned before, a bore job, different crankshaft, it can be whatever you want it to be.

One more thing, on the Engine and Parts Identification page of the forum, the first 6 or so postings are general information about engines, including a bore & stroke list for all the small blocks.
That'll make figuring out what the displacement of you engine is now.

Enjoy your build and keep us posted on how it' going!
 

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