Z vs. Z

In those days, car manufacturers really did use racing to “improve the breed.” A lot of shortcomings learned about the cars on the race track were quickly analyzed and changed on the assembly line. “Homologation,” it was called; a rule that required a certain number of production-line parts be produced in order to have them be considered legal on the race course. One such production-homologated race car was the Z/28.

In mid-1967 when the Z/28 debuted, few people other than the racers knew what it was – and even fewer could get their hands on one. Chevy purposely kept the car a bit of a secret that year, in an effort to get the limited number of hi-po parts it consisted of to the racers themselves. Only 602 Z/28s were built in 1967.

The following year, production jumped to 7,199, and by the end of the ’69 model run, Chevy’s factories had churned out 19,014 Z/28s in a single year. In that one sweet year, even your grandmother could have driven home in a Camaro with dual-quads, four-wheel discs and a suspension capable of running the high bank at Daytona. The era of the factory-direct racer for the masses had arrived .

So here we are in 1990. And, guess what? Not all that much has changed. Thanks to some dedicated Chevrolet personnel who still believe in racing what they produce (such as Camaro/Corvette engineer John Heinricy, who campaigns Camaros and Corvettes regularly in SCCA and IMSA events), the Camaros that we mere civilians buy have been race-tested and race-proven.

One only has to look as far as the dealer’s order form to see this is true. Right there on the page where ordinary folks order their V6-powered RS models is an option code that makes all the difference in the world for true enthusiasts. It’s called: “Axle, performance ratio,” code named “G92.” But there’s a lot more to it than just a set of diggin’ gears. By knowing exactly what to tell your friendly dealer, you can soon be driving the hottest Camaro to hit the streets since the ’69 Z/28.

The parlance for this special car was known as “1LE,” which was a Chevrolet internal processing code for the hot parts back in ’88 when nobody outside of a few key personnel knew anything about it. It was Heinricy’s way to get some GM engineering parts onto his team’s SCCA “showroom stock” Camaros and make it appear like they were actual production parts that any Joe with a checkbook could buy. The scheme worked, and Heinricy and crew were kicking tail soon afterward on the track. Only six “1LE” Camaros were built in that first year.

Included in that package (now officially known as “G92”) are items such as 12-inch diameter front disc brakes, special fuel tank baffling (to prevent fuel starvation on tight turns), unique shock valving, an engine oil cooler, performance exhaust system, limited-slip axle with 3.42 gearing, and even an aluminum driveshaft. But Chevy is serious about keeping these cars in short supply and purposely has not allowed for air conditioning to be ordered along with this performance-only package. Thus, you’ve gotta make the choice: cold air or a hot Camaro.

Streetwise Chevy fans of the Nineties will know to check out the fog lamps of the new top-line Camaro. If the lights are present, it’s not a G92 car. They are deleted by the factory to allow for better airflow to the engine.

The engine choices are the same as for any normal Z/28. This means you have a choice between the 5.0-liter (305 cid) or 5.7-liter (350 cid) V-8s. Both motors are fitted with 9.3:1 compression pistons, tuned-port fuel injection and low-restriction exhaust systems, and produce some heady power levels. The 5.0-liter churns out 230 horsepower at 4400 rpm, and 300 Ib-ft of torque at 3200 rpm. The big-cube Corvette 5.7-liter motor goes even further by bringing its 245 horsepower at 4400 rpm and 345 Ib-ft of torque at 3200 rpm to the performance party. Unfortunately, the ‘Vette motor is only available with a four-speed automatic and 3.23 rear gears; the 5.0-liter can be had with a five-speed and 3.42 gear.

The specs of the 305 in our test car Camaro compare well with those of its older brother, the ’69 Z/28. Both motors displace 5.0 liters (the ’69 having a total of 302 cid from a 4.00-inch bore and 3.00-inch stroke, compared to the 3.74-inch bore and 3.48-inch stroke of the 305). With a dramatically oversquare design, plus eight barrels(1200 cfm) of Holley carburetion, the old engine is a much better revver (making its underrated 290 horsepower at 5800 rpm) but proved noticeably light on low-end torque (only 290 Ib-ft of twist at a relatively high 4200 rpm). Add into the equation that the old power figures are “gross” ratings (taken on an engine stand with no alternator, power steering pump, etc.) compared to the “net” figures (checked with full accessories and exhaust system in place) used today, and you’ll realize that Chevy is currently building the best Camaro it’s ever made.

The list of parts used to create the ’69 Z/28 read like a wish list from any American hot rodder: dual quads, solid-lifter cam, dual exhaust, 11:1 compression, close-ratio four-speed, 4.10 gears, Corvette 15×7-inch wheels, four-wheel disc brakes, performance suspension and plenty more. With a wheelbase of 108 inches, and a curb weight of 3,400 pounds, the old Camaro was a real goer. Both in a straight line and in the corners.

By comparison, the new Z/28s specs look a bit lackluster. It’s hard to get as excited about computer-controlled timing and fuel delivery as it is about dual-fours, solid-tappet cams and ignitions you could tweak with. But slide behind the wheel of a ’91 Camaro and prepare to be impressed in a big hurry. With a shorter wheelbase (101 inches), wider track, longer overall length, shorter height, and less weight (3,298 Ibs.) than its predecessor, the new Z/28 has the stance to be a real road-going athlete.

The difference in handling is mind-blowing, even though the ’69 Z/28 was as good as it got in its day. On the track, the new Camaro will turn 0.90g lateral acceleration figures without raising a sweat; the old car would be lucky to get one 0.75g pass before scrubbing its front tire sidewalls into oblivion .

On the drag strip (where ETs tell it all) don’t expect to see the ’69 car in the winner’s circle. Even with its mega-cfm induction system, steep rear gearing and Hurst-shifted four-speed, the best a street-stock Z/28 could do back then was a 15.12 second/94.8 mph pass (according to test results in the August 1969 issue of Car Life). Zero-to-60 mph times of 7.4 seconds were the result (according to their testers) of the over-carburetion not allowing the motor to make power until 5000 rpm. Sure, its 7000 rpm redline made the 302 a great road race motor (especially after Trace Engineering massaged its output to 420 horsepower) but it wasn’t the best choice for street use.

Pull a new G92 Z/28 into the bleach box next to a ’69 model, and watch the owner of the old car start to squirm. With the new car’s abundant low-end torque, it rockets off the line in a blaze of tire smoke on its way to a 60-mph time of 6.8 seconds for the 305 five-speed Camaro, and 6.5 seconds for the 350 automatic. The power stays on strong as the quarter-mile rushes past, with the 350 car getting there first in 14.8/93.4 as compared to the 305’s best of 15.1/91.5.

Top speed for the two new cars is 142 mph (305 five-speed) and 145 mph (350), versus a best of 133 mph for the 302 four-speed 1969 Z/28.

In fact, as good as the ’69 car was in its day (and it was awesome, to be sure), the only place it betters the contemporary Camaro is in its original price. Although, figured in 1990’s economy, the fully loaded ’69 Z’s sticker of $5,207 would factor pretty closely to our G92 test car’s tally of $16,656.

So, what have we proven? That anyone who thinks there hasn’t been a good car built since 1971 should make a fast trip to their local Chevy dealer and drive a new Z/28 (G92 model or not). We at Musclecar Review dearly love the old performance iron (so don’t send us hate mail) but also feel it is our duty to keep an eye out toward the present and future. And with total performance machines like the new Z/28 rolling off of Chevy’s assembly lines ready and waiting for any buyer with the necessary green, we truly believe that this is the best small-block-powered Camaro of all time.