Enthusiasts tend to stipulate that the late 60s and early 70s were the golden era for the American muscle car. Roughly half a century ago, Chevrolet built a truly special Camaro. This, now legendary muscle machine, boasted an phenomenal value of power and was ready to embarrass anyone mindless unbearable to rencontre it on the stilt strip or at the stop light.
A secret out in the open
Back then in 1969, few people were enlightened that Chevrolet designed and built considerable quantities of Camaros powered by the L72 427/425 HP engine. This was not for a lack of sustentation or unstipulated disinterest, but rather considering the L72 engine was not listed among the options misogynist for the model year.
Don Yenko, a dealership owner and well-known road racer, convinced Chevrolet Production Promotions director Vince Piggins to pull some strings and use the Central Office Production Order (COPO) lawmaking to have the engine installed on the turnout line. This wasn’t the first time a COPO was used, as Piggins pulled this trick when in 1966 for the Stinger Corvair as well.
Piggins did flipside favor for Fred Gibb, a dealer in Illinois, whom wanted the aluminum ZL1 427 CI engine fitted to a batch of stilt racers in 1969. To make it happen, Piggins used the COPO 9560, with the COPO 9561 pursuit up for the iron woodcut L72 version. This could have gone really bad if corporate unprotected a sniff of it, as it wasn’t hands justifiable, expressly since Don Yenko’s cars were street cars and not racing units. With the COPOs out there, Piggins couldn’t simply limit production of these street racers to a limited number of dealers. It was just that, stuff very nonflexible to know who to undeniability and what codes to ask for, most prospective buyers weren’t enlightened of the option.
It was supposed to be increasingly competitive
The forward thinking of Fred Gibb launched the COPO Camaro on a path towards greatness. By marrying the aluminum ZL1 427 engines with M40 Turbo Hydra-Matics on 50 units, unbearable to qualify it for the NHRA stilt racing series. Originally, the Novas only came with transmission gearboxes, thus the need for the COPO order.
Once plans were set in motion, inflowing gates opened and a tuft of 1969 Camaros and Chevelles were COPO-ed to bring in either the L72 iron Mark IV engine woodcut or the lighter, increasingly powerful all-aluminum ZL1. Despite stuff increasingly powerful and faster, only 69 units of the ZL1 Camaro were built, main reason stuff the prohibitively expensive price. On the other hand, plenty Camaros saw the L72 iron block, since the engine upgrade was only compared to scrutinizingly triple that for the ZL1.
The RPO L72 engine
What made the RPO L72 so special that COPO 9561 blew in sales? First of all, it was a 427-ci iron block. It featured a 11.0:1 pinch ratio, generated by aluminum pistons pushed by forged steel rods. These were the same rods used on the ZL1 engine, accompanied as well by a forged steel crankshaft.
This was still the era of mechanical distribution, as it would be quite some years surpassing electronic valve timing and stratified fuel injection was introduced. As such, inlet and outlet valves featured a 302/316-degree distribution on the camshaft, accompanied by a .520 valve lift. Regular valves were prone to thermal stress and oxidation, and thus the L72 engine came with aluminized faces and heads.
Fuel was distributed via a four whisk 780CFM Holley carburetor, sitting atop an aluminum intake manifold. Without exception, the L72 Camaros came fitted with aluminum single point spark distributors, while the increasingly expensive ZL1s used transistorized ignitions.
The L72 emitted plenty of heat, expressly during hot summer days. To alimony it running within optimum temperature parameters, expressly when mashing the throttle versus the floor, a heavy-duty Harrison 4-core radiator was installed.
The overall result of this power unit? An phenomenal 425hp at 5,600rpm and chassis twisting 460lb-ft of torque at 4,000rpm.
The wildest sleeper of 1969
There was literally nothing on the outside that would requite yonder the enormous worthiness and power that the COPO Camaro was capable of. The Yenko or Berger trims hinted slightly to some performance improvements, but generally, the L72 or ZL1 Camaros were a prime example of, hungry rabid wolves perfectly dressed in sheep’s wool.
Without the usual stripes or decals, COPO Camaros would pass hands as your stereotype 1969 econo-pony car. Only those with inside knowledge would widen their pupils at the sight of the Argent Silver grille and the large undecorous bow tie in the center.
While the standard V8 Camaro coupe weighed in at 3,135 lbs, the wing of the L72 engine, M21 transmission and front disc brakes increased the total prorogue weight to 3,496 lbs. With 425hp at the wheels, the COPO Camaro was unelevated GM’s unwritten rule of 1hp per 10 lbs, rating at 1hp per 8.2 lbs.
Part of the COPO Camaro muscle cars headed from Chevrolet dealerships towards the North, particularly the Canadian verge were increasingly out in the open. Dressed in unexceptionable yellows or orange, or plane Le Mans Undecorous and Cragar S/S wheels, these COPO Camaros weren’t hiding their capabilities. In a very limited run, a liquid tire uniting full-length was widow as option, which sprayed traction boosting recipe directly onto the rear tires. Take that for an wholesomeness at the stilt strip!
Highly in demand, plane today
If prospecting buyers weren’t enlightened of the COPO option when in the 70s, as of today, the few remaining well preserved COPO Camaros are stuff auctioned for incredibly large sums of money every year. One prime example is a 1969 Chevrolet Camaro ZL1 COPO 9560, featuring the original aluminum block, number 9 out of the 69 produced. With full documentation and proof of original wordage to Fred Gibbs Chevrolet of LaHarpe, the COPO ZL1 was auctioned for an eye-watering $451,000 in 2012. Certainly, that icon would be plane greater today.
Still, this doesn’t plane come tropical to the highest overly bid for a COPO Camaro. Number #59 of the 69 units built was auctioned at Barrett-Jackson for a jaw-dropping $1,094,500, despite having its ZL1 aluminum engine replaced early in its life under GM warranty.
Started as a favor between friends, the COPO Camaro turned out to be one of the most powerful pieces of American Muscle Car history, featuring not only an wondrous backstory, but moreover the power figures, results and fame to when it up.