Decode engine block 3970010 !

[79RedZ]

Can’t say for sure until you pop the pan off but I have found a lot more trucks had 4 bolt mains compared to the cars.

 

[tom3]

Sometimes a big balancer on the front of the crank goes with the 4 bolt mains. Look for the 8 inch, not the 7 inch. Sometimes an extra oil pressure tap on the front of the passenger side of the block just above the timing cover can indicate a 4 bolt main block too.

 

[Francesco]

Lots of truck blocks were 4 bolt mains.

Look on the right cylinder block in from of the head. There's a machined surface and the engine codes should there if the block has not been milled. Should be 2 set of characters, one it the engine code and the other the VIN derivative. Look something like the following.

T1024TFD engine code
If the first letter in the suffix is the letter T, its a truck engine. C its a car engine.

18N300001 VIN derivative
1 - Chevy, C - Chevy trucks, T - GMC trucks
8 - model year is 1968
N - assembly plant (various) N is Norwood
last 6 match the VIN

------------------
Mike

2002 Trans AM WS6 build #3124 - Pewter
2001 GMC Ext Cab SLT Z71 - Green

My engine code is T1120DRHor(F) and the derivative is 18N540359. The derivative matches the body but if its a truck engine, then why is it in the car?

 

[Gary S]

DRH and DRF both are Camaro coded engines, not truck engines. The 18N540359 also confirms it as a Camaro engine. Either car or truck engines can be 4 bolt or 2 bolt. Trucks usually got them because the engines were expected to get harder use in a truck. Higher performance cars also got them because they expected them to be used harder.

 

[Francesco]

DRH and DRF both are Camaro coded engines, not truck engines. The 18N540359 also confirms it as a Camaro engine. Either car or truck engines can be 4 bolt or 2 bolt. Trucks usually got them because the engines were expected to get harder use in a truck. Higher performance cars also got them because they expected them to be used harder.

Sooo my engine is for high performance then?

 

[Gary S]

Z28 Camaros were higher performance than the regular Sport Coupe or the Berlinetta so the Z28 got the engines with 4 bolt mains.

 

[Zspoiler]

Those could also be used for the Chevrolet Target master crate engine. Its a good block to start with .Next to an aftermarket block.

 

[Francesco]

Z28 Camaros were higher performance than the regular Sport Coupe or the Berlinetta so the Z28 got the engines with 4 bolt mains.

Thanks! I didn't know that.

 

[JayDawg]

Forgive me, newb to Chevys seeking some confirmation on an engine my friend has in his 68 Chevrolet body... numbers we have found so far. Oil pan is not off yet.
V1I08WN (What I have been able to decode... Flint, November 08 '68 307 or '69 350)
H42 371386
17 GM 3932386 (What I have found so far, L6 327 or 302 & 350)
Can anyone help further?
Thank you!

 

[Gary S]

3932386 is a 1969 engine. There is another number stamped on the front pad of the block. It should identify what application that engine was used for. If you look up that number and post it, we should be able to tell you more.