Rare Camaro History

[solospeedshop]

Solo Smokey Update Okay found some super cool Camaro history!
Rumor has it that Chevrolet came out with a 3x2 manifold for Trans Am Racing and then the project was scrapped. They were working on this before the first 67 Camaro was made Well I can now document this I pulled off the manifold on my 69 Z28 that previous owner Larry Schreib bought it off of Smokey Yunick himself I flipped over the manifold and could not believe it is dated 2/9 /66 it's all true case solved! Thanks in advance Bill Fowler / Solo Speed Shop

[6t7 camaro]

That is way cool! I had read about those somewhere and had always wondered if any/how many had been made. Thanks for sharing!

[1967Z28]

While you have the manifold off it is a good time to clean it, but don't beadblast it.

[Charley Lillard]

I mentioned Dry Ice blasting on Facebook....

[SuperNovaSS]

That is really cool. Thanks for sharing. I use plastic media frequently to clean parts like this. It take off the dirt and surface corrosion without altering the finish.


Jason

[NorCam]

Vapor blasting is the way to go these days. David Beem is a site sponsor here and has the latest apparatus setup for proper cleanup.

You can contact him through his bodyshop I think? https://fixautousa.com/location/colorado-springs/

[Lee Stewart]

Why would they use a 3X2 setup for Trans Am Racing instead of 2X4?

[William]

They didn't.

The 3 x 2 manifold was never released to production and is not listed in the SCCA T/A Homologation documents for the Z/28.

[John Brown]

Just because it wasn't used doesn't mean it wasn't under consideration. Engineers try things to see what works best. The 3x2's must not have come out on top.

Personally, I used to run two 650 cfm Holley two barrels on a cross ram manifold in an IHRA drag class because the class record was softer than it was with a single four barrel. Rule books were meant to be read, whether it's Trans Am or drag racing.

[ELEFUNTMAN]

Nice rocker arms and headers too!! :beers:

[William]

"Under consideration" is meaningless.

Some excellent books that cover the real story on Chevrolets' involvement in racing in the '60s:

Chevrolet = Racing?
By Paul Van Valkenburgh

He worked in Chevrolet R & D in the ‘60s. Chevy had tremendous involvement with stock car racing, T/A racing with Penske/Donohue, sports car racing with Jim Hall/Chaparral. He mentions the real story behind the JL8 option. In the "under consideration" category, the Tech Center built a Z/28 with a Corvette rear axle assembly. Surprise, didn't corner any better than the live axle.

The Unfair Advantage
By Mark Donohue

There is no better source for perspective on what dealing with Chevrolet was like. The Penske/Chevrolet relationship was so bad by the end of ’69 they switched to AMC Javelins for the 1970 season. When their ’67 Camaro race car was damaged in a trailer wreck it was rebuilt with junkyard parts.

Best Damn Garage in Town
By Smokey Yunick

The consummate insider, Smokey was there at the birth of NASCAR and was involved with R & D well into the ‘70s. There are some amusing comments about the Hemi 302. A constant theme throughout the book is how cheap and difficult Chevy was to deal with.

I also have the FIA Homologation documents for the '67, '68 and '69 Z/28s.

Nowhere in any of these publications is the sb 3 x 2 manifold mentioned. And why would it be? Looks to have been cancelled April, 1966, months prior to the introduction of the Camaro. As for Smokey Yunick, he was not partnered with the factory in SCCA T/A racing. The SCCA didn't much want him around either, finding many rule infractions in the Camaros he built. That he had this 3 x 2 intake doesn't mean much either. He had buildings full of factory parts that were never used. Chevrolet may have asked him to evaluate it. Since it was never released for production, safe to say he wasn't impressed.

Sorry for the rant, attempts to re-write history need to be addressed.

[70 copo]

William,

Do you have a copy of Echoes of Norwood?

Multiple eye witnesses from the Assembly line have gone on the record as stating several examples were built for GM. Cars produced had Z/28 style stripes.

[William]

So what? Many things were considered for production.

[Fast67VelleN2O]

Very interesting that this manifold has an actual production part number and is not an 0- part, especially being dated February of 1966.

[Lee Stewart]

IMO . . . GM was still selling 3x2 engines in muscle cars during the 1966 model year: GTO and 442. The Camaro was to debut in Sept. 1966. There was no 396 option. Just the new 350 4bbl. A 3x2 option would offer higher horsepower which the Camaro would need to compete with the new restyled 1967 Mustang's 390/320 HP option.

Then the mandate came where only the Corvette would get 3x2 options and all other GM cars would lose their 3x2 engine options for the 1967 model year. And the SB 3x2 option was cancelled.

It had nothing to do with racing and everything to do with the growing muscle car market.

[rlw68]

Why would they use a 3X2 setup for Trans Am Racing instead of 2X4?


It seems like the fuel injection off the C2 327 Vette would have been a better choice for racing. I thought both of these systems were at least ten year old tech at the time.

:hmmm:

[William]

IMO . . . GM was still selling 3x2 engines in muscle cars during the 1966 model year: GTO and 442. The Camaro was to debut in Sept. 1966. There was no 396 option. Just the new 350 4bbl. A 3x2 option would offer higher horsepower which the Camaro would need to compete with the new restyled 1967 Mustang's 390/320 HP option.

Then the mandate came where only the Corvette would get 3x2 options and all other GM cars would lose their 3x2 engine options for the 1967 model year. And the SB 3x2 option was cancelled.

It had nothing to do with racing and everything to do with the growing muscle car market.

Sounds like a plausible explanation; the GTO lost tri-power for the '67 MY also.

One of these 3 x 2 manifolds turned up at a Pomona swap meet in the '80s. Think that one had a '0-' part number. The L70 was intended to be an option for the Camaro SS350. If it had proven viable, it could have been sold OTC as the cross-ram was.

[rlw68]

Sounds like a plausible explanation; the GTO lost tri-power for the '67 MY also.

Yea but no one writes songs about a Hyundai :eek2:

o_FSicQWimU

[70 copo]

William,

Do you have a copy of Echoes of Norwood?

Multiple eye witnesses from the Assembly line have gone on the record as stating several examples were built for GM. Cars produced had Z/28 style stripes.

So what? Many things were considered for production.

I am not sure if you understand? I asked you If you had a copy?

The L-70 was produced at Norwood according to workers who were eyewitnesses, and this story along with images of the engine are in the book.

[scuncio]

Are there images of the engine in the Norwood plant?

Perhaps this was a pilot build prior to cancelation.

[William]

I am not sure if you understand? I asked you If you had a copy?

The L-70 was produced at Norwood according to workers who were eyewitnesses, and this story along with images of the engine are in the book.

Nope, do not have a copy.

Not getting your point. Since the manifold has a production part number and the Engine Dress Line components are shown in the AIM, it did come close. I don't doubt L70 Pilots were built. The M08 Sport Shift option is in the '69 AIM with part numbers and that never made production either. It happens.

My position is that the L70 was intended as an option for the SS350. There is no reason to believe there was any intention to use it on the 302. For whatever reason, it never became a production engine.

[70 copo]

Nope, do not have a copy.

Not getting your point. Since the manifold has a production part number and the Engine Dress Line components are shown in the AIM, it did come close. I don't doubt L70 Pilots were built. The M08 Sport Shift option is in the '69 AIM with part numbers and that never made production either. It happens.

My position is that the L70 was intended as an option for the SS350. There is no reason to believe there was any intention to use it on the 302. For whatever reason, it never became a production engine.


I understand then that you have an opinion then. That's fine with me.:flag:

[70 copo]

Are there images of the engine in the Norwood plant?

Perhaps this was a pilot build prior to cancelation.


Yes this is correct. The L-70 was produced in plant as a prototype job for GM evaluation.

Images of this engine with the air cleaner on and off are in the book that was first published back in 2013.

[Lee Stewart]

According to this article, the L70 would make 360 HP!

But that doesn't mean none were built. Reader Lynn Dockey directed us to a question about the L-70's existence in Philip Borris's 2012 book, "Echoes of Norwood: General Motors Automobile Production During the Twentieth Century," in which Borris noted that GM initially intended the 360-hp L-70 as a sort of smaller sibling to the L68/L71 tri-power big-block 427s found in the Corvette.

https://www.hemmings.com/stories/2021/04/01/lost-and-found-could-the-l-70-be-the-rarest-first-gen-camaro-engine-of-them-all

Was the L70 more than a 350 with trip deuces? Like a higher compression ratio and a solid cam? A 65 HP gain with just a 3x2 induction doesn't add up

[1967Z28]

Phil, for clarification, if the L70 was discontinued prior to the Camaro going into production then it would seem like they would have had to be evaluated on the pilot cars, however those all seem to be well documented as to how they were built. Are you possibly saying the L70 engine was evaluated after it had been discontinued and once regular Camaro production had started?

[70 copo]

Phil, for clarification, if the L70 was discontinued prior to the Camaro going into production then it would seem like they would have had to be evaluated on the pilot cars, however those all seem to be well documented as to how they were built. Are you possibly saying the L70 engine was evaluated after it had been discontinued and once regular Camaro production had started?


Yes, kind of. The RPO was drawn and then cancelled per the timeline. However here is where it got interesting when a retiree told me "hey I was part of the L-70 build program".

In summary These were prototypes built in the same side building where the pilots were produced. These were 3X2 small blocks and were cosmetically dressed with the stripes later used on RPO Z/28. The build happened soon after regular Camaro production started in the fall of 1966.

Here is the Air cleaner image close up that I posted in another thread on this topic here back in 2016.

[1967Z28]

Interesting. Thanks for the info.