Interesting read on the only 68Z known to have had one of the experimental 302 engines installed. I remember in Hemmings about 17 years ago seeing a blue 68Z with a porcupine 302 for sale, at the time was listed around $35,000. I assume it has to be the same car. How time changes things! Especially rare muscle car prices.

Wayne posted this story this week. It's a must read if you are at all interested in the development of what some call the Hemi 302. Much of it is already well documented information, but some of it is new to me and fun to read. I especially enjoyed the comment that one of the reasons the project was killed was besides the fact the power output was disappointing, it wasn't necessary to beat the Fords.

Take a look at some of the other crossram stories in Wayne's site. I equally enjoyed the history of the SY1 since Chevrolet was driving the development for use in the 70 SCCA racing after dual carbs were prohibited.

Here's the link:

http://guinns-engineering.com/Quang%20Le%20Hemi.htm

Enjoy!

Interesting

It's a cool car but from what I have read in the past and seen in person there are more than 3 of those engines floating around. Charlie Lillard had one in a yellow '69 Z/28, Reggie Jackson Had one on an engine stand and put one in a car other than a Camaro and there was another '69 featured recently in a magazine that had one. None were factory installed. As for the rest of the story they never got an appreciable amount of power gain out of the heads so I wonder about the stickers claiming 600hp. Seems funny they would put one in a '68 when the intent was to use them in the '69 race season... Anyway this should be a real interesting thread as it's a real cool engine from the past...

Not 100% sure but thought one in a magazine several years ago supposedly came from the estate of Smokey U. and new owner installed in a yellow camaro. History of engine quite interesting for sure.

Thanks...love the information!:hurray:

I've seen one engine Reggie had at his shop here in Monterey...neat piece.

Wayne has some cool stuff and they had a nice display at Carlise this year.

I think they are just saying this Z the only 68 Z with a porcupine 302 in it but it is not clear when it was installed and who installed it.
I don't think they are saying it was done by Smokey.
SY had some 67-68 Camaros that were highly modified race cars with BB and SB engines but he never got them through SCCA tech inspection. He set some speed records with them at Bonniville.
In 1969 Smokey sold the Camaros to go work for Ford.
Don Yenko bought one and raced it in 1969 winning the Citrus 250 at Daytona and some other races.

here is a pic I took at Carlisle

I had the yellow 69 Z that had one of those engines in it. A friend has it now. It was last covered in print in the May 2003 Super Chevy. The blue 68 just sold in Scottsdale at the Russo-Steele auction for over 200K. I told my friends when I had it that it was just a really neat engine stand. The guy selling the 68 tried telling me that all the other engine parts other than the first 3 were just production pieces. Mine as I recall was lettered with the same 0- part #'s and I think was letter D. Reggie still has a complete engine on his shop floor.

Wayne does a great job of researching this stuff. There's some great info. I never knew why Smokey got these engines.
I recall there being 5 of these engines at Smokey's garage sale. I didn't know about these 3, but that means there's at least 8 of them around. Who knows if more left Smokey's over the 20 years he had these motors. Noone knows the whereabout of them all, most went into 69's (like Clill's), but another one could be in a 68......

This is a Camaro someone dropped a funky motor in. It's interesting but ..... And that air cleaner label is more than just a stretch.

The relationship of the motor to this car needs clarified, IMO. The first part of the article says this car has the hemi engine and the 4WD brakes and "What makes it even more unusual is the fact that this equipment along with an electric fuel pump was installed at the dealership prior to vehicle delivery." He just need to clarify that statement and say when the motor was installed.
The car itself seems to have some interesting history, but it's not discussed.

I probably shouldn't have titled it 1 of 1. Obviously the car never came this way, the motor was stuffed into it years later. What I meant was this is the only 68 I am aware of that a procupine motor has found it's way into. What made it more interesting was the fact that years ago a blue 68 Z was listed in Hemmings with a porcupine 302 in it. Same car?

The more people I talk to about the porcupine project it becomes clear that no one is certain just how many were developed and exactly where they ended up. The responses here seem to back that comment up. Considering the extra hardware produced there could hae been more motors assembled in addition to the complete motors. I know I purchased a new set of the hemi pistons from Trisha Yunick a few years back, no I do not have them today. Standard bore with part number ESK2528 CL-C D 316937. No idea what any of the numbers meant. Considering all the hardware that Maynard Jr displays in Hooper's book and there's certainly enough spare parts floating around to build a few more. The crossram intake base would be the unobtainable piece I'm sure. I'm told the lid is the same as the standard crossram lid.

So this 68 has a porky 302. Reggie has/had a porky 302, was it the silver 69 recently featured in a magazine? If so there's 2. Someone posted they saw another porcupine motor in his garage, there's 3, was it a 350 or 302? Maynard Jr shows at least 2 porcupine 302s in Hoopers book, still in his possesion or did they find their way into a car? There's been one for sale on ebay recently by a dealer in Michigan. Clill's former yellow 69Z had a porcupine motor. Maybe Charlie can shed some light on this but didn't that car belong to Price when Dwiggins installed the engine and if so wasn't the engine Dwiggins bought from Smokey a porcupine 350? Did Steitlow also own this car at one time? I say that because the other porucpine 350 sold from Smokey's shop I spoke to the owner and he said Dwiggen's purchased the other 350 motor at the same time. So there's a couple more. I've also been told the GM Tech Center in Warren had one for years on display until recently, where did it go? Same goes for the museums in Daytona and Talledega I've been told had a motor each on display for some time. Surely some of these are the same motors and have changed hands, but how many?

So based on all that there are at least 4 porcupine motors known to exist in vehicles at this time. There are or were 4 on stands in private owners hands and 2 said to have spent at least some time in museums or may still be there either on display or in storage. Bottom line is there weren't many and they came either as 302 or 350 shortblocks. I keep hearing about the 5 assembled motors, but it sure sounds like there may have been a couple more like Kurt suggests.

I think the 600 hp is a stretch, Yunicks dyno sheets show about 475-480 as the peak hp.

Interesting topic, maybe some with more info can jump in and set us straight on the numbers.

I think there are two of these engines at Rick's First Gen in Athens, GA. One in a 69Z (very nice car) and the other on a stand in the showroom. Very cool pieces!

Yes there are 2 at Ricks one in a car and the other on a stand,,the oddest thing i noticed about the engine was the center exhaust port on the right side head,, it was shaped differant from the other 7 ports,

If my car had 600 hp I should have looked in the glove box for the missing 150. My car was a real 69 RSZ that Dave Tinnell sold Carl Dwiggins. Dwiggins bought the engine at Smokeys auction and had Tinnell restore the Z and install the engine. The headers were made from test stand headers. Reggie had a Silver Z with the engine and I think there was a second silver Z with one that maybe Al Maynard had. Dwiggins sold my yellow car to a Ed Ulayte ? Then it went to Price, then me, and it is now with Fred Phillips in Canada.

In Smokey’s book, I think he claimed something like 200 sets of the porcupine heads were cast. This could be true if Chevy planned to run this head configuration in Trans Am. The rules to homologate parts for TA stated that the items had to be available to the public in sufficient quantities. So Chevy had to make a pretty good amount of Z race parts such as cross rams, big sway bars, 4 wheel disk, hoods etc.
TA rules allowed service parts but they had to be pre-approved by SCCA.
I think Chevy was nervous about the Ford tunnel port heads, which looked like they could make a lot of power. Chevy wanted to win and since they were not supposed to be making racing parts they had Smokey do some of the work on the heads. Smokey was also faster and less expensive then Chevy Engineering.

In the end, the Ford tunnel port 302 did not really work that well in TA so there was not really a need for an improved Chevy 302 head. The standard Traco 302 was making good power.

Another thing interesting on Whynn's display was the guy Jerry Thompson. He was a Chevy engineer in the 60s and raced Corvairs and Corvettes. Him and 2 other Chevy engineers had a side business called RST Engineering, who did race engine and suspension parts. Jerry ran the Yenko Stinger Corvair and won a national Championship in 1967 beating the factory Group 44 Triumph Racing Team and had a long relationship with Yenko.
Jerry worked on development of the prototype 302 Cross ram. At Carlisle he showed a picture of an early test manifold built from the base of a 1965 Corvette FI manifold being run on a dyno at Chevy. cool stuff
When doing research on the Yenko Stormer, which was a early 67 Z/28 racecar Yenko was marketing, some old receipts were found where early Z race parts were bought from RST Engineering.