OK chevy guys. I have to get a new head for my truck. The numbers on the Engine are 3970010 and V01O6TYZ and 06F368785 there are also numbers under the block that say 10 and 20 under that. I think its a 350 4 bolt out of a truck but want to make sure. Please help!! Mike
According to my source, it could be a 68 327, or a 69-79 350. That is just going by the 3970010 code. -Joe
Ok here goes, According to what I found V01O6TYZ lists out as follows VO Built in the Flint plant 01 Built in January 06 on the 6th day of the month TYZ = Suffix code: 1975, 350 cid, Conv. cab truck, 160 hp, models C10 -2500 series I am 99.9% sure that I decoded it correctly but here are the links so you can see for yourself. if you click on the first link it will then direct you to the second one. I believe if memory serves me correctly the other numbers are just ID numbers nothing spesfic. Most likely any 350 head form around that time period will work just fine. Just a plain jane old truck motor. You could put LT1 heads etc. or aftermarkets if you wanted to also. Hope this helps http://www.nastyz28.com/sbchevy/sblock.html http://www.nastyz28.com/sbchevy/spcode9.html
bbls should mean barrels, like carb (2 or 4) and I think racefab posted a few months ago and said that the 010 and 020 casting blocks are pretty sought after.
The only way to know if a 350 is 2 or 4 bolt main is to remove the oil pan and look. There are no codes designating a block's main cap style, and Chevrolet used the same casting for both.
Your main ID is that VO no. stamped on the pad in front of the right cyl head. All are correct about casting no.s. Any 3 digit letter code (TYZ in your case) usually designates 1970 or newer, almost always when a 3 letter code starts with a T it's from a truck...BBC or SBC.
The partial VIN 06F368785 also tells you something if you know what to look for....I think you might have the first character wrong, could it be C instead of 0? C is used for Chevy trucks. 6 is the last digit of the model year, F is the assembly plant (Flint) that built the truck. yes, the three letter code beginning with T means it's from a 1970 or newer truck. Generally the 70s truck 2bbl 350s were 2 bolt main, and the 4 bbls were 4 bolt mains, but that's not 100%...you'll find some of both...
Here is something I know a bit about. The 3970010 casting # you referenced was produced from the late 60s through the mid 80s. They were used in just about everything at some point. This block was produced in both 2 and 4 bolt main versions. All LT-1s for the Z-28 Camaro, all SS 350 models, and heavy duty trucks, got 4-bolt versions of this block. Some El Caminos, light trucks, and vans got it as well. Most 0010 blocks, but not all, were 4-bolt blocks through the mid 70s. In the late 70s, the 2-bolt became the more common except in the 1-ton and heavier trucks. Your block appears to have come from a 75 truck or El Camino and probably has the 4-bolt mains. There is no real way to tell from any external clues. If it IS a 4-bolt, it may have a forged crank as well. Look for the wide, ground parting line on the crank. The 010 and 020 #s refer to the tin and nickel content of the castings. The "High Nickel Content" blocks are sought after for their low wear and durability qualities. More importantly though, you want to try to match up the casting # of the head, if that is what you need to replace. There were many variations on the sbc heads and almost any of them will bolt on, but differences in the heads will produce a power imbalance that could lead to other problems down the road. Small block heads are a dime a dozen, so take the time to get the right one. I mismatched some sbc heads in my younger days, and ended up with a busted crank and a few misguided connecting rods. Engine harmonics are not to be toyed with. Oh well, Live and learn as they say. Hope this helps. Good luck. By the way here is another good # decoding link: www.mortec.com
I am not 100% certin but I believe that all truck motors were 4 bolt main. The difference between a four bolt main truck motor and a car motor such as a Z-28 or a Vette motor for example was the deck height. Resulting in a higher compression motor. I'm really shaking the old cobwebs here but I believe this to be correct. As was mentioned if you don't replace the head with the exact same configfuration you might have some sort of imbalance but I wouldn't be too concerned. As long as the combustion chamber size and the valves are the same size you should be ok. I assume this is not a race car so a sbc is a pretty forgiving motor. Unless you we're to run a before and after on an engine dyno I don't think you owuld notice any difference. I belive you mentioned that your original head was cracked? If so why not just look in to having a machine shop weld it? It's doen all the time and the reliability isn't compromised as long as the guy doing the job knows how to nickle weld and the crack is in a place where he can weld it your good to go.
There were 2 bolt main 350s put in trucks...mostly the 70s trucks with 350 4bbl engines were 4 bolt main, most had the 010 casting # block. Deck heights were the same on all of them...but if you measure the decks they're out of square, the machining was really crappy. Figure on .010 to .030 block decking just to get it squared up!
He's thinking of the BIG BLOCK truck motors. They had .400" taller decks because the truck pistons used 3 compression rings. Great stroker blocks if you don't mind paying for custom length rods. What's the head casting #?
Yup I think I releasized that abouttwo hours after I posted it laying in bed.Told ya I was blowing out the cobwebs.... lol unfortunetly my memory is going the way of the Caddy tailfin and what use dot be my boyish good looks Man am I in F-ing trouble
Yup I think I releasized that abouttwo hours after I posted it laying in bed.Told ya I was blowing out the cobwebs.... lol unfortunetly my memory is going the way of the Caddy tailfin and what used to be my boyish good looks.......HA! Man am I in F-ing trouble
don't sweat it, you still know more about this stuff than many folks here...even if you forgot how some of it fits together! I thought I knew a lot till I started reading this board, there is a LOT of knowledge here! it's humbling
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