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BigD69
04-04-2018, 08:27 PM
I'm in a disagreement with a buddie who says Chevrolet made a factory 427 Chevelle in 1966 and 1967, I don't think so, who is correct?

SS427
04-04-2018, 09:15 PM
NO ONE has EVER come up with ANY proof that Chevrolet built a 66 or 67 427 Chevelle due to the 400 cubic inch rule though many have claimed it. On the other hand, MANY dealers did 427 Chevelle swaps in that era. I knew of a few myself. This has been a long standing argument on the Chevelle community for many years.

Lee Stewart
04-04-2018, 09:40 PM
1966/1967 427 Chevelle . . . Urban Legend . . . along with 1965 327/375 HP F. I. Chevy II, Chevelle and El Camino

fsc66
04-04-2018, 11:32 PM
1966 and 1967 General Motors production documents show no production of a 427 motor in either year.

Paul

BigD69
04-05-2018, 11:56 AM
Looks like I won that bet, thanks guys!

novadude
04-05-2018, 12:46 PM
Looks like I won that bet, thanks guys!

You can never really "win" these arguments, because there is always the guy out there that insists that the factory would build anything you wanted back in the day.

As if a production line cranking out millions of cars is going to stop and do special requests (not to mention the Engineering, supply chain logistics, etc involved with something as significant as a different engine).

markinnaples
04-05-2018, 01:12 PM
1966 and 1967 General Motors production documents show no production of a 427 motor in either year.

Paul

Not sure I understand that as their were 427's in Corvettes and big cars as well starting in late '66.

SS427
04-05-2018, 01:36 PM
I think what Paul is saying is during the 66/67 year there are no documents that have any 427 RPO codes assigned to a Chevelle of any kind. The Tonawanda plant never assigned a code for that engine (in a Chevelle) so therefore they could not have built and installed one.

markinnaples
04-05-2018, 01:39 PM
Ah, thanks Rick. That is too bad, as one would think that the 427 and the Chevelle were made for one another.

olredalert
04-05-2018, 01:43 PM
----Late 65, Mark! And, to add to that, there were test 427 vehicles in 1965, mainly 1965 Corvettes, a few of which escaped the factory into private hands. One specific 65 was serial # 5 off the assembly line. It was initially built as a fuel injected roadster but taken to the tech center and had a 427 transplant. The car is fairly well known in Corvette circles. I have seen and inspected it closely.......Bill S

SS427
04-05-2018, 02:10 PM
Ah, thanks Rick. That is too bad, as one would think that the 427 and the Chevelle were made for one another.

They were but corporate rules prohibited anything larger than a 400 cu in engine installed in an intermediate or smaller bodied car as from what I understand they did not want those cars to compete against the Corvette. That obviously changed somewhat with the COPO (limited production) and then again in 1970 with the LS6 and Corvette had nothing anywhere near that Chevelle.

HawkX66
04-05-2018, 03:08 PM
You can never really "win" these arguments, because there is always the guy out there that insists that the factory would build anything you wanted back in the day.

As if a production line cranking out millions of cars is going to stop and do special requests (not to mention the Engineering, supply chain logistics, etc involved with something as significant as a different engine).
Not to be argumentative, but isn't that what COPO essentially did?

Tracker1
04-05-2018, 04:37 PM
Not to be argumentative, but isn't that what COPO essentially did?

COPO worked with significant numbers of cars/trucks - large orders with dozens or hundreds of vehicles. And/Or with a high-volume dealership that had clout because they themselves sold THOUSANDS of vehicles, e.g., Yenko or Gibb. Hardly one-offs.

If Don Yenko had harnessed the COPO process a little more aggressively in 1966, yeah, I believe he could have made 427 Chevelles happen. But he didn't.

Which is a shame because it would have made for a fantastic car.

HawkX66
04-05-2018, 04:49 PM
COPO worked with significant numbers of cars/trucks - large orders with dozens or hundreds of vehicles. And/Or with a high-volume dealership that had clout because they themselves sold THOUSANDS of vehicles, e.g., Yenko or Gibb. Hardly one-offs.

If Don Yenko had harnessed the COPO process a little more aggressively in 1966, yeah, I believe he could have made 427 Chevelles happen. But he didn't.

Which is a shame because it would have made for a fantastic car.
You're talking about relatively significant COPO orders, although 50 cars isn't really a lot. COPO was also for more simple requests wasn't it?

edit: I guess it really wasn't. Even still, the 69 COPOs Gibb ordered wasn't really a lot of cars it seems. Definitely not one offs though.
"Instead of placing an order for Camaros using the “Regular Production Option” sheet, used by dealerships for performance and styling upgrades, a dealership began ordering Camaros using the Central Office Purchase Order (hence the name COPO), which was generally reserved for adding alterations to municipal fleets."

https://www.gmpartscenter.net/blog/brief-history-of-copo-camaro

427TJ
04-05-2018, 05:11 PM
You can never really "win" these arguments, because there is always the guy out there that insists that the factory would build anything you wanted back in the day.

"Experts." I stopped hanging around my cars at shows because of "experts" who would talk you to death if you let them.

Lee Stewart
04-05-2018, 07:26 PM
I guess Chrysler was different from Chevrolet. They WOULD build anything, specifically Hemi cars. You just had to go to the right dealership (like Grand Spaulding Dodge) or know someone at Chrysler. You read their ordering forms that state that the Hemi was available in certain cars and not available in others. Yet there are Hemi 4 Doors (1966), Hemi Belvederes (1967), Hemi Coronet 440s (1968). They even proudly show a 1969 Hemi Charger which was not available (had to be an R/T) in one of their PR photos. ALL built by Chrysler - no dealer conversions.

novadude
04-05-2018, 10:22 PM
Not to be argumentative, but isn't that what COPO essentially did?

Those cars were built in larger numbers, and the COPO was approved to further an agenda within Chevrolet. The COPO 427s were to support backdoor racing activities. A work-around to corporate policy. It was all about promoting brand image at a time in history when drag racing was "hot" in popular culture.

I've never seen any evidence of such a program in 66-67. It would have required substantial effort and cost, and they wouldn't have authorized it just because a person wanted to buy one that way. I would imagine you would have needed solid upper management connections and a 50 car minimum before they'd even consider it.

It's also worth noting that lots of stuff appeared in PR photos that never made it to production.

61 vert
04-05-2018, 11:13 PM
I believe the 66 yenko stinger corvairs were copos because of the dual reservoir master cylinder. Please feel free to correct me if I am wrong.

BigD69
04-06-2018, 09:10 PM
Thanks for all the replies, I did win the argument as he said 66 and 67 Chevelles had 427s which I said they didn't from the factory. 1969 would have been the only time that happened with very few built at the factory as a COPO Chevelle.

69hurstSC
04-10-2018, 02:55 PM
I think what Paul is saying is during the 66/67 year there are no documents that have any 427 RPO codes assigned to a Chevelle of any kind. The Tonawanda plant never assigned a code for that engine (in a Chevelle) so therefore they could not have built and installed one.

Was there an RPO code assigned to Pete Estes's Z/28 convertible?