Correct 1966 TI voltage regualtor

[Michael G.]

Happy Thanksgiving all.
Assembly/judging manual calls for my '66 to have a 1116368 voltage regulator with tranistor ignition, no air. I've located a 1116378, what if any differences would there be between the two. Would using a standard 1119515 be an issue? Any thoughts here? Thanks.

[Joe L.]

Re: Correct 1966 TI voltage regualtor

Happy Thanksgiving all.
Assembly/judging manual calls for my '66 to have a 1116368 voltage regulator with tranistor ignition, no air. I've located a 1116378, what if any differences would there be between the two. Would using a standard 1119515 be an issue? Any thoughts here? Thanks.

Michael-----


As far as Corvettes go, I now believe that the transistorized voltage regulator was used only for 1965 and only for those cars equipped with K-66 AND C-60. Various GM references seem to indicate that the transistorized voltage regulator was also used for 1966 with K-66 and C-60, but I don't think that ever actually occurred. In any event, if it did occur it was by far the exception and not the rule.

For the 1965 model year, the GM #1116368 transistorized voltage regulator was used. Strangely, I can find no record of the discontinuation and/or supercession of this part number. However, I am virtually certain it was discontinued sometime in 1965 and replaced by the GM #1116378. IF any 1966 Corvettes had been built with a transistorized voltage regulator, I think that this is the one they would have received. However, as I say, I now don't think that any were ever built. In any case, if any had been built for 1966, I am virtually certain it would have applied to cars with K-66 AND C-60, just like in 1965. So, whether or not any were built, I don't think your non C-60 car would have had a transistorized voltage regulator.

By the way, although the transistorized regulators were used in very few pre-69 Corvettes, they were used in many other Chevrolets and GM cars. Primarily, their use was limited to applications using a 62 amp alternator. No pre-1977 Corvettes ever used a 62 amp alternator. These 62 amp units, used during the 63-69 period for some Chevrolet and GM cars, were a larger and different series alternator than the 10DN series used for all 63-68 Corvettes.

[Michael G.]

Re: Correct 1966 TI voltage regualtor

Joe,

Thanks for the info. As I understand it, you feel my '66 with K-66 didn't come with a tranistor voltage regualtor? . Would that then mean it came with a 1119515? (Vehicle had a replacement voltage reg when purchased). Would the use of a 1116378 pose an issue electrically or functionally?

Michael

[Jack H.]

Re: Correct 1966 TI voltage regualtor

My Delco Remy Application Index, shows the 1116368 was offered as a direct, drop-in, replacement for the 1119515 electro-mechanical voltage regulator through 1965. Starting in 1966, the 1116378 was favored for use in HIGH amperage charging systems (above 61A), but still downward compatible with the earlier '6368 and '515 regulators.

I believe the issue here is one of efficiency in handling high output alternators (above 41A) especially when the car's load profile could change dramatically (A/C engaged or disengaged).

So, can you use the '6378 without risk of damage...you bet!

Is it factory correct for your car? Probably not.

Were solid-state V-regs actually installed on Corvettes from the factory in '65 and '66? The answer is 'Yes' if you believe the factory AIM books and what's listed in the ECR revision history of the their drawings...

[Michael G.]

Re: Correct 1966 TI voltage regualtor

Ok guys...are you saying the 515 regualtor "most likely" would be the correct application for my TI? Believe my alternater to be the 696.

Michael

[Jack H.]

Re: Correct 1966 TI voltage regualtor

Yes, there is no evidence for the use of transistorized voltage regulators in '66 Corvette production. The current NCRS Judging Guide only recognizes the electro-mechanical '515 regulator for all '66 Corvettes.

BUT, these transistorized v-regs WERE used on certain '65 Corvettes. It took a combination of options on the car to call for the change from an electro-mechanical to solid state v-reg (L76 + C60 or L79 + C60 or L79 + K66 + C60).

However, some very early 396 (L78) cars were found to have gone out the door (by accident?) with SS v-reg's on them. The 'accident' might relate to certain aspects of the L78 being similar to C60 cars (battery on the LH side, Etc.) and the use of terminology ('installs the same as') by Chevy in AIM based option descriptions.

Now, could there have been some confusion at model change over (65 -> 66)? Might St. Louis have 'used up' left over inventories of the SS v-reg on early '66 cars? And, might prior owners have 'upgraded' their cars to the SS v-reg? The answer is yes. But, the burden of proof falls on the owner to document his/her '66 Corvette actually shipped from the factory with a transistorized voltage regulator.

[Wayne M.]

Re: Correct 1966 TI voltage regualtor

Michael -- to add to what Joe and Jack have said, here's proof that it was used in Chev production, that there were problems identified in the spring of 1965, and a work-around issued (see pics of 2 sheets of the TSB).

Also here's from a similar thread back in May 2007.
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(archives) In spite of the parts manuals saying that these were a SERVICE item [replacing identical production] on '66 Corvettes, I don't believe that ever happened. The 1116368 suffered failures due to high voltage discharge when "blower motor, air conditioner, compressor clutch, ignition coil, etc. were (simultaneously) turned off with the ignition switch". (TSB # 1115, April 22, 1965). The interim fix was to add an external suppression diode harness # 2977253 at the voltage regulator. This shows up in '65 AIM UPC K66, sheet 5. Then, when this diode was incorporated into the design of the voltage regulator, the number changed up to 1116378 (I've only seen this stamped # with the letter "B" suffix). It's a mystery to me why both the 368 and the 378'B' both appear in the 1966 and 1967 P&A30's if they knew the '368' was faulty. Neither of these TI volt reg's are fully transistorized units; the field relay remains electro-mechanical.
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I've seen [or have] '368's with stamped assy dates of 4H, 4K, 4L, 5E, 6A, 6B (proof they were still making them in spite of known problems, probably until the '378 B' was released).

Never yet heard of any reports of a mid-to-late '65 with this diode harness.

I ran a '378' - dated 7J, on my late 396 for 10+ years -- works beautifully, and looks good to boot .

[Dick W.]

Re: Correct 1966 TI voltage regualtor

Save your self some headaches. Use the transistor regulator as "wall art" in your shop and install a 515 on the car. The transistor unit was somewhat less reliable than a Yugo

[Michael G.]

Re: Correct 1966 TI voltage regualtor

OUCH ....that comment'll leave bruise! Thanks guys.

Michael