BBC Identification [Archive] - Chevelle Tech

: BBC Identification


Shay Feral
May 6th, 10, 9:49 PM
I've been looking up the numbers to one of my Big Blocks and depending on the website I reference it could either be a 69 396 or a 72 402, and I was wondering if you could help me determine which engine it really is.

3999290

Dean
May 6th, 10, 9:55 PM
3999290 was used on 68-70 396 blocks and 70-72 402 blocks.
Late 69 "396" motors were actually 402 motors.

Got any other numbers?

Shay Feral
May 6th, 10, 10:02 PM
Are there more numbers on the block? Cos the heads are from a 427 and I'm almost certain the internals are not original.

Mike
May 6th, 10, 10:09 PM
Get what you can -more is better

http://www.yearone.com/updatedsinglepages/Id_info/gm_engine_id/gmidimages/endinedetail1.jpghttp://www.yearone.com/updatedsinglepages/Id_info/gm_engine_id/gmidimages/enginedetail3.jpg

Shay Feral
May 7th, 10, 7:45 PM
Engine ID TO415CTB

Mike
May 7th, 10, 8:20 PM
Heres the choices ,although there all the same ,you can see which vehicles they came in:
CTB 72 402 Impala 240 LS-3 TH-400 4-Brl A.I.R.
CTB 72 402 Chevelle 240 LS-3 TH-400 4-Brl A.I.R.
CTB 72 402 Camaro 240 LS-3 TH-400 4-Brl A.I.R.

Dave Birdwell
May 7th, 10, 10:36 PM
Whoever is referencing the 290 block as a pre-72 piece is incorrect. The casting numbers changed every year basically from it's inception in 1965 through 1971. The 68 block ends in 323, the 69 block ends in 272, the 70-71 block ends in 854, and the 72 block is the 290 that you have.

Shay Feral
May 7th, 10, 10:59 PM
Heres the choices ,although there all the same ,you can see which vehicles they came in:
CTB 72 402 Impala 240 LS-3 TH-400 4-Brl A.I.R.
CTB 72 402 Chevelle 240 LS-3 TH-400 4-Brl A.I.R.
CTB 72 402 Camaro 240 LS-3 TH-400 4-Brl A.I.R.

Gah, I was hoping I had a 396...

But what can I say, I paid $300 for the engine. I'm just glad I have a big block!

69 Post Sedan
May 8th, 10, 1:58 AM
Whoever is referencing the 290 block as a pre-72 piece is incorrect. The casting numbers changed every year basically from it's inception in 1965 through 1971. The 68 block ends in 323, the 69 block ends in 272, the 70-71 block ends in 854, and the 72 block is the 290 that you have.

Dave, you are correct but most of the internet links that I have seen say the same thing which is it was available in 1968.

What's really funny is the 1974 CE in my car is a 3999290 4-bolt main block that was cast on March 15th of 1973. There is no mention of it being available in 1973.

Here are some links that came up on Google when I searched for 3999290.

http://www.mortec.com/bbc.htm
http://www.chevcarclubvic.org.au/technical/v8bb_chev_eng_casting_numbers.htm
http://montesrule.freehomepage.com/custom.html
http://www.ajgeneral.com/bbc_block_casting_numbers/

They all have pretty much the same results.

3999290 396 68-69 Truck Light Duty
3999290 400, 402 70-72 Truck
3999290 402 70-72 Truck Light Duty
3999290 402 72 Pass, Chevelle, Camaro, Nova
3999290 400 72 Pass, Chevelle, Camaro, Nova 4 BC

Kurt :beers:

DaleM
May 8th, 10, 2:42 AM
Gah, I was hoping I had a 396...

But what can I say, I paid $300 for the engine. I'm just glad I have a big block!The 396 grew to 402 cid in late 1969 and remained so for a number of years. Basically it is the same as a 396, just bored .030 larger.

Dave Birdwell
May 8th, 10, 3:57 PM
They probably list it for those years, as it was used as a service replacement for those engines. :yes:

jetblue69
May 9th, 10, 6:46 AM
Well technically you do have a 396. Just punched 30 over like mentioned earlier. Just tell everyone it's a 396 punched 30 over. They're not going to know and technically speaking you aren't lying either so everyone wins.

Cory 66
May 10th, 10, 10:42 AM
I'll give you more than you gave for it if you don't want it.

kettbo
May 10th, 10, 1:40 PM
Shay,

Congrats.....
Now get some 063 or other closed chamber heads on there to bump the CR up, add a modest cam, any you'll have a peppy engine

Shay Feral
May 11th, 10, 2:27 PM
I'll give you more than you gave for it if you don't want it.

Unless I come up with either a 396, 427 or 454 I probably wont turn loose of this big block cos I plan on using it. But I've got more than $300 invested in the engine.

Shay,

Congrats.....
Now get some 063 or other closed chamber heads on there to bump the CR up, add a modest cam, any you'll have a peppy engine
I've got a set of 427 closed chambered heads for it, and I'm gonna be ordering a nice camshaft for it soon.

The 396 grew to 402 cid in late 1969 and remained so for a number of years. Basically it is the same as a 396, just bored .030 larger.

Yeah, I knew about that.