anyone know a lot about the 1st gen Z/28's?

i always heard thet they came with the 302/290HP motor but i was talking to a guy today that said that Z/28 and the 302 were in no way connected....

anyone?

 

That guy is full of ****. The 67-69 Z-28's came with the DZ302 which was rated at 290 horses in the street version. I have heard that the cam in the race versions made all its power over 4000rpm and could make close to 500 horsepower. The 302 was built in order for the Z-28 to be legal in the Trans Am series which had a 305 cubic inch limit for the cars. However, I believe 1970 was when GM would no longer associate itself with organized motor sports and the 302 was discontinued. Hope this clears things up.

 

This belongs on the History board, but I'll answer it anyway...

SCCA had, might still for all I know, a limit in the Trans Am series of 5.0 liters on engines. For years, people had been taking a 283 crank and putting it in a 327 block, since this didn't cost much CID but gave a considerable improvement in upper RPM performance. So when Chevrolet decided to enter that series, they borrowed what the hot-rodders were already doing (we called it a 301) and made it their Trans Am entry. SCCA also had a rule wherein the cars had to be a production version, with 500 copies made or some such. So Chevrolet invented a RPO code for a totally stripped-down Camaro, with this "302" engine. IIRC no options whatsoever were available on the 67 version of this, only a heater came standard, I don't even think you could order it with a radio. It was strictly a single-purpose road-race car. It came with this 302 motor, solid cam with double-hump heads, M22 4-speed, & 3.73 gears. You could order a factory set of "headers" as a dealer-install option. The RPO code was Z28. It was rated at 290 HP.

When word got around, everybody wanted one. They weren't real fast off the showroom floor, I recall them as low-mid 14s cars. But it was real easy to get about 100 more HP out of them with the headers and a single-plane intake (they already came with a Holley 780 square-flange carb), and with a set of 4.56 gears and some racing tires, they were 12-second cars without popping a valve cover.

The only car it was ever possible to get the 302 from Chevrolet in was the Z28. You couldn't order it in any other chassis, or even any other variant of Camaro. There was no optional engine for the Z28 either: to get a 302 you had to order RPO Z28, and if you ordered RPO Z28, it came with only a 302. So, basically your friend is as full of s*** as a Christmas turkey.

AFAIK that was the first RPO code that ever made it put into the public consciousness. People had no idea what it meant, all we knew was that if you went to the dealer and ordered that RPO, you got the most unbelievably bad ride you had ever seen. It was wildly popular; Chevrolet expanded the program the next year to where you could even get the RS option which included such un-race-car-like pieces of useless weight as vacuum-operated disppearing headlights. In 70½ (April 1970 actually) when the 2nd gen Camaro came out they continued the Z28 option, but changed it to a 350 with the smae heads, cam, and so forth.

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"So many Mustangs, so little time..."
ICON Motorsports

[This message has been edited by RB83L69 (edited June 22, 2001).]

 

to add a little bit more to what has been said DZ wasn't the only engine code for the 302. my 1971 chiltons manual list at least one other code but it's in the garage and i'm not. if i recall the other code was CN, but that's just a guess.

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ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

 

i was thinking that the 302 and Z/28 were stuck together but he told me that his friend had a 69 RS/SS Z/28 with a 396 from the factory. after that the sh*t hit the fan.

 

No such thing as a RS/SS/Z28. In 69 the SS either with a 350 or 396, and the Z28 with the 302, could have also been equipped with the RS appearance package which consisted of a different rear fascia and diappearing headlights and some other trim details. It was not possible to have a car that was both a Z28 and a SS, any more than you can have a 89 RS Z28. Even if his friend's cousin's girlfriend's sister's husband's boss said he knew somebody that said he might have seen something about one in a magazine, it still didn't happen.

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"So many Mustangs, so little time..."
ICON Motorsports

 

my 68 is a ss 396 car i don't know for sure but i was thinking (always gets me in trouble) the z/28 and ss camaros had the same suspension with the z/28 having the m22 302 set up.

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ICON Motorsports
1st & 3rd
MM Black Diamond 538 F&AM

 

Had to throw in my two cents worth. The engine code DZ was for the 69 302 engine. The 67 and 68 engine code was MD. You could get the RS appearance package with either the Z/28 or the SS, but the SS and Z/28 packages were never combined on the same car. The Z/28's all came with the 302. With the SS, you had the option of either a 350 or 396. If your friend really wants to know who the bad boys on the block were back then, he needs to research the 427 powered Yenko and ZL-1 Camaros.

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89RS w/350 TPI; 69RS/SS w/450 HP 350/Muncie 4-Speed "Too weird to live, too rare to die."