'69 Turbo 400 code?

[William]

Stan, the CX & CY use converter 8626358. They also use the same valve body 8624854, but different control valve assemblies.

CX uses case 8623457, valve assy 8626613.

CY uses case 8626058, valve assy 8626367.

CX & CY have other internal parts not used on other versions. The cases aren't unique.

[Ray Morrison]

William,

The casting number on my CY coded 400 is 8623462, the short tail housing is 8624486.

Stan, I still believe the Transmission Identification sheet of 7-12-68 is for the CY code transmission as they came before the CX. Could the X on this document be the reason you think it is for the CX? The Gibb cars were built with a redesigned Turbo 400 for racing purposes. These first redesigned 400's were called experimental automatics (X). These transmissions are believed to be the first automatics built for Chevrolet with a high horsepower, solid lifter engine. According to documents I have, 39 pages of Hydramatic Production Parts list, the CX code was added on 10-25-68, meaning they were built for 69 cars. Would Turbohydramtic have issued this letter this far in advance on building the CX? If any of you have the November 1968 issue of Popular Hot Rodding and the article about the Harrell Novas, notice in this article they refer to the experimental transmission as 69's, however, we now know the Gibb cars were built on the tail end of 68 with these transmissions as a COPO Nova, which was never mentioned in the article. Both the Cy and CX coded transmissions shared likness in that they were built for high performance applications in 68 & 69, L-78's, L-72's, etc. Could some of the extra experimental transmissions have been built for Gibb, or someone else? Since Mark Fuss has a Harrell Nova that is an automatic, Which is not one of the 50 Gibb COPO's, but could Harrell have built his car with one of these? His Nova supports an L-88 engine. How many other Experimental Automatics could have been built for warranty? There are all kinds of questions that are still unanswered?

Ray

[Ray Morrison]

William,

The casting number on my CY coded 400 is 8623462, the short tail housing is 8624486.

Stan, I still believe the Transmission Identification sheet of 7-12-68 is for the CY code transmission as they came before the CX. Could the X on this document be the reason you think it is for the CX? The Gibb cars were built with a redesigned Turbo 400 for racing purposes. These first redesigned 400's were called experimental automatics (X). These transmissions are believed to be the first automatics built for Chevrolet with a high horsepower, solid lifter engine. According to documents I have, 39 pages of Hydramatic Production Parts list, the CX code was added on 10-25-68, meaning they were built for 69 cars. Would Turbohydramtic have issued this letter this far in advance on building the CX? If any of you have the November 1968 issue of Popular Hot Rodding and the article about the Harrell Novas, notice in this article they refer to the experimental transmission as 69's, however, we now know the Gibb cars were built on the tail end of 68 with these transmissions as a COPO Nova, which was never mentioned in the article. Both the Cy and CX coded transmissions shared likness in that they were built for high performance applications in 68 & 69, L-78's, L-72's, etc. Could some of the extra experimental transmissions have been built for Gibb, or someone else? Since Mark Fuss has a Harrell Nova that is an automatic, Which is not one of the 50 Gibb COPO's, but could Harrell have built his car with one of these? His Nova supports an L-88 engine. How many other Experimental Automatics could have been built for warranty? There are all kinds of questions that are still unanswered?

Ray

[Rowdy Rat]

William,

Thanks for posting the part numbers... I certainly appreciate it!

<BLOCKQUOTE><font size="1" face="">quote:</font><HR>Stan, I still believe the Transmission Identification sheet of 7-12-68 is for the CY code transmission as they came before the CX. Could the X on this document be the reason you think it is for the CX?<HR></BLOCKQUOTE>

Ray,

To be honest, I'm not familiar with the document you are referring to and I don't have a whole lot of background information on the Gibb Novas or the special THM 400s so I'll defer to you and others on that topic. My comments referred exclusively to 1969 Corvettes that used the "heavy duty" THM 400. The cars that I have observed have all been "CY" code ranther than the "CX" code used by the 1969 COPO cars.

Regards,

Stan

[JoeC]

To sum it up a little, The CY trans was used in 68 69 and 70? The CX trans is 69 427 COPO only? Anyone know of any CX trans in a non-427 COPO car?

[Chevy454]

OK, fellas, here is part of the documentation Ray has: 400TH INFO

[Mr70]

I must say this topic is getting very interesting for me.It all started on one mans outside inquiry.
Also to sum up:
The CY was definately used in 1970 LS-6 Chevelles,and up to 1974.
The CW was used on my L-78 1970 Chevelle,up to 1972.

CY first,then the CX later.
Rays documents look convincing for me to believe the CY trans was used in the 1968 Gibb Novas.The CY trans.was the one mentioned in the 7/12/68 letter.Not the CX as I thought.

The CX trans. wasn't out till 10/25/68.And COULD be specific for 427 COPO cars with 4:10 rears only?We need to look at serial #'s at the reunion for this,which I hope to attend.

A December built 1969 L-72 Impala used the CY trans.and not the CX.

The 1969 Special Hi-perf Corvettes used the CY code trans.,and not the CX.

I have never seen the CX trans.used in the 1970 model year.So it may be safe to say it was only used in the 1969 models.
Rick




[Edited by mr70 (08-19-2001 at 12:31 PM).]

[Woj]

Originally Posted by JoeC

To sum it up a little, The CY trans was used in 68 69 and 70? The CX trans is 69 427 COPO only? Anyone know of any CX trans in a non-427 COPO car?

I have a CX trans from a 69 Nova L78.

All 69 Turbo 400s that I have seen have a yellow ident tag. No guarantee on that one though.

Also, Grady's 69 Camaro has the VIN stamped on the CX trans at the top of the bell housing. I don't have a picture of it, but the screw driver in these photos shows where I found the VIN on this TH400 Coded CA. FWIW.

Phil Woj

[WILMASBOYL78]

The 69 L78 Nova used the CX trans...along with L78 Camaro & Chevelle and COPO cars. 1970 was the first time the high shift point tranny was offered with a small block [Deuce and Z28]. It appears from the listings in Colvin's book, there were a number of applications for the CY coded unit up until 1974. Not sure if the shift points were lowered to match up with the engines available...it would make sense though.

**I have seen high shift point TH400's with the partial VIN stamped on the bell housing.

Originally Posted by Woj

I have a CX trans from a 69 Nova L78.

All 69 Turbo 400s that I have seen have a yellow ident tag. No guarantee on that one though.

Also, Grady's 69 Camaro has the VIN stamped on the CX trans at the top of the bell housing. I don't have a picture of it, but the screw driver in these photos shows where I found the VIN on this TH400 Coded CA. FWIW.

Phil Woj