The Stovebolt Site Forums The Shop Area General Truck Talk 283 and 327 engine

I recently bought a 65 GMC pickup, and i was wondering what the engine is. I saw a number on the front of the block, their was a number above the long one so it read like this 10115
104471379
Is this the right number, or is the correct number on the back of the block?
Thanks

There will be a number/letter combination on a machined pad in front of the passenger's side cylinder head. The letters at the end of the number will identify the engine size, year, and horsepower rating. Several websites have lists of engine number conversions, and the Hollander interchange manual that most auto salvage yards use will also have an engine number matchup.
Jerry

So that means that if u are standing at the front of the truck, it would be at the far left hand side?

Thanx

Exactly. There is a ledge right under the head with these letters. Go to nastyz28.com & it will break it down for you.

References to left, right, front and rear are normally made assuming you are sitting in the drivers seat looking forward.
The pad should on the area of block that extends forward beyond the passenger side head.
On the the number two plug side.

I think this site will answer all your ???.www.the dirt forum tool box .com

hey guys thanx. I found it in front of the drivers side. Its a 283. But i was thinking, i had a 350 in the garage that needs to be rebuilt, but when i checked the block number it has the same serial number as the 327, so how do i find out which one it is?

Thanx

if the same number appears on the 327 and 350 blocks, either the 327 is actually a 350, or your reading the block casting number, which may be the same for 350/327

the number you want to identify that exact engine is on a small pad that projects out from the block right below the head/valve cover on the passengers side - this pad was where they stamped the exact engine buildup info as it was being built, and it appears nowhere else - "serial numbers" were not duplicated!

Bill

ok, is this the correct one then, if it is could someone identify it for me.
c71100024

k0812kyz


Thanx

Hi,
Try this it may help: http://www.mortec.com/
Bill

ya, i've tried that site already, i can't decifer what any of it means, pretaining the serial numbers i have.

this info is from mortec


1968 3970010 327 - - 2 A

1969-79 3970010 350 185 370 2 or 4 car, truck, Vette


They are the same numbers

Hi,
You have the info...what this means...is that you have a large journal 327, and a 350. The large journal 327 uses 350 size bearings. Same block. Earlier 327's usually have a casting # that ends in 890. The earlier 327 uses 283 size bearings.
Bill

hey, thanx alot for all the info guys. But could u "dummy" what u just said down a little. So is this a 327 or a 350, or both?

the 327 and a 350 is the same block

Hi,
That's all the info that the casting # will give you (that it is either a 327 or 350). This: k0812kyz and actually (kyz) Are these capital letters on your block? These letters determine the displacement,horsepower, and car that the engine came in. I dont have a handy reference at the moment...but, three letter codes indicate a '70 or newer engine and thus it should be a 350. No 327 in '70 or newer cars.
Bill

There are two (for the purposes of this discussion) types of Small Block Chevy (SBC) motors: small-journal and large-journal. From 55 to 67 the main bearing journals were 2.3" in diameter, the rod journals were 2.0 inches.

Starting in 1968 (67 for the 350) the main bearing journal size was increased to 2.45" and the rod journals went to 2.1". This is the difference between large and small-journal motors.

Going a little further, the 327 has a bore of 4.0" and a sttoke of 3.25" The 350 has the same bore (4 inches) and a 3.48" stroke. So in essence, the 327 and the 350 are the same except for the crankshaft, pistons and rods. The block is the same.

So you can have a block that is listed as either a 327 or a 350 based on the casting and stamping numbers, and either could be correct, depending on what's inside.

To make things more interesting, the 327's crank is the same as a 307 (a much lower performance motor). So you can make a 327 out of a 307 by boring it out to 4" (and hoping you don't hit the cooling jackets during the boring process) and using 327 pistons.

The same holds true for a 350: you can make it into a large-journal 327 by using a 307 crank, pistons and rods.

All of what I've written is relative to large-journal motors. The small-journal SBCs (265, 283, 302 and early 327s) use the same size main and rod journals and bearings...but the bottom end parts are not interchangeable with the large-journal motors. Other parts are.

I dunno if this has cleared things up or muddies the water. If you really wanna get overwhelmed, read thru the book, "Chevy By The Numbers 1965-1969" by Alan Colvin. There's enough stuff there to keep your head spinning for weeks. (Years in my case.)

Btw, don't get me started on 400 SBCs or 396/402/400 BBCs. That's one awful can of worms.

Very well said ChevyAsylum!

Dano

darn... all I could make out was 0630DB - 307 or 283?