'65 L-78 technical information search

[Duke W.]

Prior to embarking on correcting the distributor installation on a '65 L-78 that I documented in another thread I dug out Vol. 8 No. 3 Corvette News that has an article on the new big block engine, including some basic tune-up data along with following comment.

"Tune-up procedures are spelled out in detail in the 1965 1/2 Corvette Interim Shop Manual Supplement."

Now I know that the 1965 Corvette Shop Manual Supplement has no information on the L-78 because it was published months before the 396 was introduced, but I have never seen this 1965 1/2 Corvette Interim Shop Manual Supplement.

Does anyone know of this document and whether it is still available?

Duke

[Joe L.]

Re: '65 L-78 technical information search

Prior to embarking on correcting the distributor installation on a '65 L-78 that I documented in another thread I dug out Vol. 8 No. 3 Corvette News that has an article on the new big block engine, including some basic tune-up data along with following comment.

"Tune-up procedures are spelled out in detail in the 1965 1/2 Corvette Interim Shop Manual Supplement."

Now I know that the 1965 Corvette Shop Manual Supplement has no information on the L-78 because it was published months before the 396 was introduced, but I have never seen this 1965 1/2 Corvette Interim Shop Manual Supplement.

Does anyone know of this document and whether it is still available?

Duke

Duke------


It's a little beat up but I don't think this has the info you seek on the 396. The second one does, though:

https://www.ebay.com/itm/333834016430?hash=item4dba0ed6ae:g:~f4AAOSwEV5f4k6 ~

https://www.ebay.com/itm/203189924086?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160908105057%26meid%3D1dc23b8a619d470aaa1dbd2cadfa8b15%26pid%3D100675%26rk%3D2%26rkt%3D15%26mehot%3Dnone%26sd%3D333834016430%26itm%3D203189924086%26pmt%3D1%26noa%3D1%26pg%3D2380057&_trksid=p2380057.c100675.m4236&_trkparms=pageci%3A16ed8128-b0f2-11eb-994d-ce09f318d81f%7Cparentrq%3A525476eb1790a9b13c71c6acffe5f8a3%7Ciid%3A1

[Ray K.]

Re: '65 L-78 technical information search

Duke / Joe

I have my original copy of the 1965 Chevrolet " Interim " Shop Manual. It contains information on all the 1965 396 engines both passenger car and Corvette, as well as details on the new Turbo Hydra-Matic transmission, plus the 3 speed fully Synchronized Transmission. A publication put out by Bill Thomas Race Cars in Anaheim, called the 396 Performance Handbook, was basically a reprint of the Chev Interim shop Manual featuring only the 396 engine section of the manual Thomas did add some of his own perspectives on engine building and tuning.

Ray

[Joe L.]

Re: '65 L-78 technical information search

Duke / Joe

I have my original copy of the 1965 Chevrolet " Interim " Shop Manual. It contains information on all the 1965 396 engines both passenger car and Corvette, as well as details on the new Turbo Hydra-Matic transmission, plus the 3 speed fully Synchronized Transmission. A publication put out by Bill Thomas Race Cars in Anaheim, called the 396 Performance Handbook, was basically a reprint of the Chev Interim shop Manual featuring only the 396 engine section of the manual Thomas did add some of his own perspectives on engine building and tuning.

Ray

Ray------


I agree. The Bill Thomas book is virtually a copy of the interim shop manual with his added info. The reason I suggested the versions shown above is because they usually sell for far less than the Bill Thomas book. Attached is a copy of my copy of the Bill Thomas book. I purchased this brand new about 50+ years ago.


DSCN3926.jpg

[Duke W.]

Re: '65 L-78 technical information search

Thanks for the info, guys. I'll pass it along to the owner. It's interesting that the Corvette News article says 1965 1/2 Corvette Interim..." not Chevrolet, but I expect that was the result of the unconscious CN editors Corvette bias, and they actually meant Chevrolet.

Roy - how many pages is the 396 section of that '65 1/2 Chevrolet Interim... manual. Short enough to photocopy, by chance?

Duke

[Ray K.]

Re: '65 L-78 technical information search

Duke,
The 396 engine mechanical section is 55 pages, with another 8 pages for Cooling and an additional 30 pages for Fuel and carburetors. There is also an Engine Tune-up section which is about 10 pages. In my opinion, the mechanical section and some of the tune up specs offer the most relevant information.

Ray

[Duke W.]

Re: '65 L-78 technical information search

Thanks, that's too much to copy, but I'm sure the owner can find a copy to buy.

Duke

[Scott P.]

Re: '65 L-78 technical information search

Duke, the manual also goes by ST-71. I have one I can mail you so you can see it and get out what info you want and then return to me.
Fogaley@sbcglobal.net Scott

[Duke W.]

Re: '65 L-78 technical information search

Thanks, Scott. The owner is trying to find one to buy, but if he strikes out we'll take you up on your offer.

Duke

[William F.]

Re: '65 L-78 technical information search

initial advance: 10*
start 0*@1000
15*@ 1800
28*@4600
vacuum 0*@8 in
15*@15,5 in
Some of this especially vacuum advance sounds strange but comes for an old Corvette news article introducing the 425 hp 396.

[Duke W.]

Re: '65 L-78 technical information search

The VAC was poorly choosen, same 201 15 as on the '63 327/340, also a mistake, as I quickly found out had a significant idle stability problem. Typical L78/72/71 idle vacuum in neutral is 14" @ 900, so a 15.5" VAC doesn't pass the Two-Inch Rule. That's why I recommend the 12" B26 for SHP mechnanical lifter big blocks. It also works on L-36/68, typical idle behavior is 14" @ 900. A 8" B28 might be necessary with Powerglide since they pull less vacuum at the same idle speed in Drive.

Duke

[Randal M.]

Re: '65 L-78 technical information search

A new reprint is also available on Amazon: https://www.amazon.com/1965-Chevrole.../dp/B00BGBAXSG

[Duke W.]

Re: '65 L-78 technical information search

Thanks for the link!

Duke