Re: L78 396/375 HP Long Block CKO Stamping
 

Guys, I understand, acknowledge and agree with the examples you have given on 854 Casting dates and machining date spreads/differences...

However if I may repeat my question...........

Would somebody with more knowledge than I, please explain how this 290 casting which Colvin says wasnt introduced until the 1972 model year received a 1970 CKO(L-78)deck code???

Who has a real world example of a born with L-78 Chevrolet Model using a 290 Block casting ?????

Who has knowledge of any L-78 Camaro, Nova, Chevelle receiving a dealer replaced LIKE engine with ????? casting # block and ???? deck code (i.e. "CE")
Regards, <font color="purple"> </font>

Re: L78 396/375 HP Long Block CKO Stamping
 

Chuck, my 70 Fathom Blue L78 car has a dealer installed 290 4 bolt CE block. This car is an original L78 built 4th week of Feb. 1970. Dial chevrolet in Center Reach,NY(Long Island)did the replacement for the original owner in 1973. Don't know what else to say except these things are out there. I don't think you will find a 290 block that was factory installed as an L78.


wilma https://www.yenko.net/ubbthreads/imag...ins/3gears.gif

Re: L78 396/375 HP Long Block CKO Stamping
 

Tom,

What Chuck is asking is how an engine produced in 1972 can receive a 1970 CKO code. i assume that your replacement block is NOT stamped with a CKO code.

Re: L78 396/375 HP Long Block CKO Stamping
 

[ QUOTE ]
Chuck, my 70 Fathom Blue L78 car has a dealer installed 290 4 bolt CE block.

wilma https://www.yenko.net/ubbthreads/imag...ins/3gears.gif

[/ QUOTE ]

What is the replacement engine stamped?

Rick H.

Re: L78 396/375 HP Long Block CKO Stamping
 

Chuck,
No BB engine built after the 1970 model year was designated as an L78 unless it was used as a replacement engine. CKO was not used in 1971. Never used in 1972 as well.

Any engine used as a replacement was stamped CE. I would really question any 1972 replacement engine with a 1970 factory stamp.

Please post pictures of the stamp and casting numbers.

Rick H.

Re: L78 396/375 HP Long Block CKO Stamping
 

I have a theory: seem to recall reading somewhere that the hi-perf BB motors were a late cancellation for 71 model year. Maybe some blocks were produced and stamped in antcipation of being used and then relegated to warranty or service replacement. My engine satmp is CE360285 casting date is E2572.

wilma

Re: L78 396/375 HP Long Block CKO Stamping
 

I will post pictures of my stamps and date codes if it helps. Isn't there a bunch of 71 and 72 blocks running around with 70 LS6 stampimgs too?


Jason

Re: L78 396/375 HP Long Block CKO Stamping
 

My 69 Camaro SS has a 71 cast L-78 warranty block with it. It is stamped "CE1XXXX"

Rich

Re: L78 396/375 HP Long Block CKO Stamping
 

As we have seen any replacement block would be stamped "CE"

With this block being a late May 71 casting it could have been used in 1971 but with a September block stamp I think it was an attempt to be used in 1972 or restamped (nasty word) according to the original 1970 block stamp. https://www.yenko.net/ubbthreads/imag...lins/dunno.gif

Again, CKO was not used in 1971 or 1972 and any block correctly replaced under warranty would have been stamped with the replacement code.

Rick H.

Re: L78 396/375 HP Long Block CKO Stamping
 

Tirebird's LS6 T/A has a CRR code(?) and was one of the last crate motor LS6 available in '73-74.It had to come from Berger Chev. to L.A.