Small Block Chevy Rear casting number 3970010 and front casting numbers 1416454889 K01-09-CMF Can anyone tell me what size motor is this and what year it is?

3970010 69-79 302/350 car & Truck 2 & 4-Bolt Most common

http://outintheshop.com/faq/casting/castings2.html

302s are quite rare. The 3970010 350s were put in pickups and cars through most of the 70s and are far more common. Chances are about 98% that it's a 350.

1969-1979 302-350ci.

Small Block Chevy Engine Block casting and code identification
http://www.73-87.com/chevy_ids/blockid.htm
Chevy Small Block Engine Casting Codes

From this chart - I think you may be misreading the number - 3970010 is possibly the actual number: Which makes the engine pretty old 68-72 350 V8 - 4 bolt main. I included past this number so that you can see that the number you posted doesn't actually exist. And thus my conclusion that the 9 is most likely a 0. Hope this helps. 3970010 350 69 Corvette late 69,4 bolt main 3970010 302 69 Camaro Z/28,Late 69, 4 bolt main 3970010 350 69-79 Truck 2&4 bolt main 3970010 350 69-79 Pass,Chevelle,Camaro,Nova,MonteCarlo 2&4 bolt main 3970010 350 70 Corvette 300,350,370 HP 4 bolt main 3970010 350 71 Corvette 270,330 HP 4 bolt main 3970010 350 72 Corvette 200,255 HP 4 bolt main 3970014 350 69-77 Pass,Chevelle,Camaro, Nova,MonteCarlo 2 or 4 bolt main 3970014 350 69-79 Truck 2 or 4 bolt main 3970014 350 72 Corvette late &undefined;72,200 HP,255HP 4 bolt main 3970020 307 68-73 Pass,Chevelle,Camro, Nova 3970020 307 69-73 Truck 3970024 307 69-73 Pass,Chevelle,Camro, Nova,Truck 3992386 327 68-69 Pass,Chevelle,Camro, Nova,Truck Large Jounal

The casting number for a small block chevy is located on the rear left side if the engine where the transmission bell housing would bolt to. Where did you find these numbers?

The VIN number should tell you all of that if you use the internet to decipher what letter or number to look for to determine engine size etc

Hey spoofy, that is a good block casting...Chevy used that from 1969-1979. The Vette, Camaro, Chevelle, Nova, Monte Carlo and Trucks all had this engine. If it's a 4 bolt main, the chances it came out of a Vette are very good. The engine number you give does not cross reference.
I hope this helps.

Go to www.nastyz28.com and i think you will find what your looking for.These blocks have a high nickel content which makes very strong.This will be a good motor to build horse power with.

Those casting numbers would indicate the engine is a 350