[mywifes69camaro]

I am fairly certain that I have a 396 Truck engine. The casting number on the back of the engine on top of the bell housing flange is 3969854. I am trying to figure out what year the block is and what is it, 396 or a 402? The stamp on the front of the block is TII24TBG. I did find something on the Intake which leads to me to believe this is a truck engine, the casting number on the intake (3955287) comes back as a 1970-71 402 330hp cast iron oval port with a quadrajet carb. Any help would be much aprreciated.

 

[RWENUTS]

Mortec shows 69-72 396 or 402. You might have the last digit wrong Because
your suffix code of TBG says it’s a 366 truck motor.
Is there about 1/2 inch space above the water pump flange up to the deck?
if so it’s a tall deck.
pics help.

https://www.mortec.com/bbc.htm

Decoding Big block Chevy engine suffix codes and stamped numbers Q - YZ

Decoding Big block Chevy engine suffix codes and stamped numbers: Q - YZ.

nastyz28.com

Some pics in here on tall blocks.

Identifying Chevy engines

www.crankshaftcoalition.com

 

[mywifes69camaro]

Mortec shows 69-72 396 or 402. You might have the last digit wrong Because
your suffix code of TBG says it’s a 366 truck motor.
Is there about 1/2 inch space above the water pump flange up to the deck?
if so it’s a tall deck.
pics help.

https://www.mortec.com/bbc.htm

Decoding Big block Chevy engine suffix codes and stamped numbers Q - YZ

Decoding Big block Chevy engine suffix codes and stamped numbers: Q - YZ.

nastyz28.com

 

[RWENUTS]

Another ‘tell-tale’ is back of block has HIPER PASS in big letters above the crank flange.
That’s for normal deck. Truck tall decks don’t have that.
and suffix codes have been known to be wrong before.

 

[ericnova72]

If it has a standard deck intake manifold on it, there is no way it can be a tall deck block unless the intake is bolted on with spacer plates between the intake, the heads, and the lifter valley china walls.

Mortec says it is light truck(1/2, 3/4, 1 ton) 402, 310 hp, TH-400 trans, L-47 designation code

TBG

1970

Truck

402

310

400

L-47 10, 20, 30

 

[mywifes69camaro]

Here are some images of the measurement from the water pump to the top of the deck. After re-reading your comment, I measured from the center of the water pump hole instead from the top of the flange. Looks to be a low deck block. Just for clarification, do i have a 366 block or a 402/396 block?

 

[RWENUTS]

Congrats!
it be a 396/402.
Like I said, somtimes the suffix codes are wrong.

 

[ericnova72]

Mortec says it is light truck(1/2, 3/4, 1 ton) 402, 310 hp, TH-400 trans, L-47 designation code

​

TBG

1970

Truck

402

310

400

L-47 10, 20, 30

I should have been more clear, that "TBG" code above came from NastyZ28.com and not Mortec.

From the latest information, looks like a correct code string to me for the application. short deck block, just like the casting number confirms.
"T1124TBG"
T- Tonawanda Engine Plant
1124 is month/month/day/day so 11/24 = Nov 24th
TBG the string quoted above