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Username Post: Hemi-Crossram, Check Out the Rarest 1969 Camaro Ever        (Topic#331624)
Founder & Grand PoohBah
Posts: 17572
Loc: Orange County CA.
Reg: 03-15-99
12-28-15 10:26 AM - Post#2598192    

Excerpts taken from a great article by SuperChevy
See Full Article Here

Attachment: 1-1969-crossram-hemi-z28-camaro-front.jpg (56.79 KB) 108 View(s)

From the outside, the car looks like your everyday, ho-hum Cortez Silver Z/28 with a ZL2 hood and the D80 spoiler package. Climb into the interior and the driver is met with black standard buckets, console with gauges, a Hurst shifter, rosewood steering wheel, an in-dash tach, and windup windows. Look under the car and the 3.73 rearend with the JL8, four-wheel disc brake system is ready to go from top speed to no speed without a hitch. GM knew the meaning of “purpose-built cars” in the ’60s.

Attachment: 4-1969-crossram-hemi-z28-camaro-engine.jpg (52.19 KB) 124 View(s)

Sitting proudly in the super-clean engine bay is the only known surviving all-aluminum, Hemi 302 crossram in existence. It appears that some of the folks at Chevrolet’s engineering department were thinking to the future by using existing technology available at the time. The O- prototype, 327 block is straight from Zora Arkus-Duntov’s Grand Sport Corvette closet.

Attachment: 6-1969-crossram-hemi-z28-camaro-carburetor.jpg (58.28 KB) 125 View(s)


Posts: 472

Loc: Columbia, MO, USA
Reg: 08-31-02
01-03-16 09:00 PM - Post#2599823    
    In response to Tony

I have stopped here at least three, maybe four times w/o saying anything.

So I'm going to open my pie-hole!!

Nice car and collection of parts but IMHO, that's about all it is!

Chevy never installed this setup in a Camaro that I know of.

And as for the parts being massaged by everybody, hey, this most certainly wasn't done back then to a production car.

And it's funny that everybody associated with this are gone so that there isn't anybody around to authenticate it.

I know, I'm being an censored here, but that's just me!

I would have bought a March, '67 Z-28 if I would have known it was coming out, but not knowing better, I bought an Oct., '66, '67 350SS/RS Camaro instead. And my car is a SS/RS because I checked the SS line before the RS line when I ordered it!

And if you want to hear a good story!!

I was working up at Detroit Edison at their Belle River Power Plant years ago and got to jawing with the Maintenance Supt.

He was a young guy about like me at the time and he asked me if I wanted to buy a new test mule Camaro with a ZR1/LT-5 in it. I coughed and said, What??

He said that his girlfriend worked for GM in the Tech Center and that said car was for sale for a price. All factory done.. And I had no reason to call him a liar at all.....

Don't know if he was telling me the truth or not so take this however you want to....


ChevyTalk Subject Matter Expert
Posts: 21215
Loc: See the USA in your Chevr...
Reg: 12-06-99
10-24-17 05:27 AM - Post#2711920    
    In response to pdq67

The only one? I cry BS. Smiley Yunick had one and several of these engines. A lucky collector purchased it at the smiley auction several years ago and restored it properly. It was then shown at the GM Carlisle event and it was awesome to listen too. Chevrolet's answer to the Ford (did I just say that?) 302 tunnel port engine Killed by GM bean counters. By the way. This same collector had several sets of these cylinder heads in display. One lucky guy!

Bowtieollie Moderator

Posts: 9
Loc: PA
Reg: 12-10-15
10-24-17 06:05 AM - Post#2711924    
    In response to bowtieollie

Well, to make a slight correction, the fellow's name was Smokey rather than Smiley. Beyond that I don't think it's a matter of who has / had one but whether or not the motor worked as intended.

I've heard "of" them but not much about them. Did they run well? Does anyone know any performance specs or history to share? Curious minds want to know!

Valued Contributor
Posts: 4781

Age: 67
Loc: Addison, IL
Reg: 05-28-10
10-24-17 08:38 AM - Post#2711947    
    In response to pdq67

RS was just a trim level option and only showed on the badging if it was a plane jane Camaro. SS or Z28 badging would always be displayed if the Camaro was an SS or Z28 even if the RS option was ordered.

Forum Newbie
Posts: 2

Reg: 12-16-16
10-24-17 09:59 AM - Post#2711954    
    In response to Larry38HA

No it never worked as intended. It was one of those "Looked better on paper" ideas that just didn't work.

I once read that GM and Smokey were unable to show that the gain in HP was going to be worth the additional tooling, engineering and production cost. So that project was canned. Smokey Yunick has been quoted as stating the heads “…weren’t worth a crap…” and described the project as “…a one-half million dollar trip to $hitsville.”

Best number on the dyno was 450 hp @ 8000 rpm and that a race ready 302 was much better.

This also was the second time around for an aluminum hemi head for the small-block. Zora Duntov built several of them for the original 377c.i. Corvette Grand Sport in 1963, with twin plugs per cylinder, and it didn't work out very well either.

I believe this was once discussed on a Yenko site and that there was a yellow 69 with one of these hemis and that it once belonged to a Charley Lillard.

Rare? not so sure. Sounds like there were several of these out there from the several articles that I've ever read.

Bel Air kiwi 
"3rd Year" Silver Supporting Member
Posts: 4256
Bel Air kiwi
Loc: New Zealand
Reg: 04-24-14
10-25-17 12:37 AM - Post#2712056    
    In response to repsol17

Hi Guys, cool car and interesting engine, but I don't think that is actually a Hemi at all.
What it really is is an open chamber poly angle head.
To be a real Hemi it would need a much deeper bowl and opposed valves.

I can understand why it would not deliver as a race head as the chamber is just too open and soft. The opposition was the Ford Boss 302 and that head was very similar in valve layout to this, but had closed chambers.
The Chevy approach of open chamber is what Ford used in millions of Cleveland 2V engines so the design works for road use.

That said it is dearer to make and won't pass emissions as easily.

Sorry guys but I doubt that GM built and sold this car in this configuration. We always had to restore or destroy these experiments. Its a cool car but no different than putting a SOHC 427 in an Edsel. Its a re-power.

Cheers Kiwi

48 3100 RHD, 51 Deluxe 4DR RHD, 51 Bel Air parts car, 52 Bel Air P-Glide LHD. Others 23T, 32 Tudor, 58 Edsel pacer 4DR HDT, 79 F250 351C RHD. 69,70,82 Capri. No mobile, no TV, and no Jap cars.

And when it was laid to waste, they called it peace.

Edited by Bel Air kiwi on 10-25-17 12:42 AM. Reason for edit: No reason given.

"14th Year" Platinum Supporting Member & Moderator
Posts: 14542
Age: 72
Loc: St. Louis, MO
Reg: 12-11-03
10-26-17 01:22 PM - Post#2712248    
    In response to Bel Air kiwi

I don't think any article stated this engine was ever sold. Certain operators got different oddball parts over the years for testing and evaluation.

Tom 65-70 Full Size Team Moderator

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65 Impala SS Tahitian Turquoise

Senior Member
Posts: 8825
Age: 69
Loc: Loganville, Ga.
Reg: 04-28-00
12-20-17 07:36 AM - Post#2718529    
    In response to 427SS65

Hey T @!

In Memory of Mike McVeigh- The "Mad Spring Wacker" He roams the Forums of CT forever in our hearts and minds!


Edited by wagonmaster on 12-22-17 08:22 AM. Reason for edit: No reason given.


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