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Author Topic:   castig numbers
Dirt Full Roller

Total posts: 34
posted April 11, 2005 02:32 PM  
just got a new small block chevy trying to figure out what i got.block casting is 3970010 i no this a 350 casted feb 02 1968 head and intake is what i can't find head is 3986388 are these double hump heads? or not 64cc or not? intake is 340264 with gm 17 under neath it.what hp am i looking at with this motor being stock?

Dirt Maniac

Total posts: 165
posted April 11, 2005 02:58 PM  
Does the heads have any accessory holes on the front or rear of them? Also check to see if there is a small hump cast inthe front of the head where the accessory holes would go, If it has the hump then it is the hump heads.

Dirt Freak

Total posts: 354
posted April 11, 2005 04:26 PM  
"388" casting heads are late sixties/early seventies 350cid truck heads. Small valve 1.71 intake and 1.5 exhaust. Approximately 74cc. Designed for high torque and low speed.
The intake casting number sounds like the "small" two barrel(?)

Dirt Full Roller

Total posts: 34
posted April 11, 2005 07:13 PM  
how much hp would this engine have. is it worth running in a enduro car?

Dirt Roller

Total posts: 20
posted April 22, 2005 08:17 AM  
1968-71 3986388 307 1.72 1.5
1972-76 3986388 350 1.72 1.5

1969-79 3970010 350 185HP-low 370hp-high
1968 3970010 327 no listing for hp

Not all these numbers are 100% accurate but are very close.

If you have a 1968 block...
VIN Code Format
The vin code format is stamped onto most engines. The format consists of divisional identification number, model year, assembly plant designation and vehicle serial or sequence number.
In 68-69 model cars, the serial (VIN) number of the car the engine was installed in is stamped next to, or under the engine code ID.
Starting in 1970, the serial number is stamped either above the oil filter, somewhere on the block pad (in front of the cylinder head), or on the transmission flange somewhere. Chevrolet issued technical service bulletins to indicate which engines were to recieve a vin stamp, so who knows what could have happend (or not happened).

VIN code format Example: 13N100001
(1 = Chevrolet, 3 = 1973, N = Norwood, 100001 = Production sequence of vehicle VIN)

I did a google search and found this info.

[This message has been edited by DirtMirt (edited April 22, 2005).]

Dirt Freak

Total posts: 374
posted April 22, 2005 08:52 AM  
If it runs, don't smoke to much, and is an 8 cylinder it is way good for an enduro car!

Dirt Roller

Total posts: 20
posted April 22, 2005 10:33 AM  
Any V8 chevy engine is good to start out with.
If you do a compression check on the cylinders, they should read between 125 and 150 for a good strong engine. Anything over 100 will be enough to fire the cylinder.
generally they should all read with/in 10 lbs of each other to have a nice smooth running engine.
I had a 305 from the boneyard that read between 50 and 125 at first, but after hooking up 2 batteries(24 volt) and using starting fluid I got the cylinders to pump up.I guess the heat generated expanding the rings and reseated them enough to run. When the engine first fired I could feel the exhaust manifold and tell which ones were firing from the heat @ each exhaust port.
If an engine has been sitting for a while it is a good idea to squirt a little tranny fluid down the cylinder and let sit over night to free up the rings as not to break them. it will smoke at first, but it burns away.
hope this helps some

Dirt Freak

Total posts: 217
posted April 22, 2005 09:49 PM  
have you tried
has a lot of head and block casting numbers.

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