engine life. - I just bought a 2010 CrewCab with an aluminum 5.3. Just wondering what the service life of the engine is vs. a cast iron block. I know ...

The 1969 ZL-1 all aluminum 427 cubic inch Corvette motor was the most powerful engine that was ever offered in an American built automobile. It was the direct descendant of the L-88 427 engine and the all aluminum Can Am racing engine of the same era. Although factory rated at 430 HP, the actual output was more like 585 HP after tuned headers were installed in place of the restrictive factory exhaust manifolds.

First. Most powerful. Quickest. Only one Chevy combines it all: the 1969 Chevrolet ZL1 Camaro. It went a step beyond the 427 Yenko and even the mighty L88 Corvette, to where few production muscle cars tread.

Never heard of the super-high-performance Camaro ZL1? That may be because Chevy only built 69 copies.

They were basically blank canvasses for the most committed muscle car mavens.
Drawing a bead on NHRA Super Stock drag classes, Chevy performance guru Vince Piggins authorized the factory to fit a batch of '69 Camaros with a version of the 427-cid V-8 used by the all-conquering Can-Am Chaparral. This actually was another of Piggins' Central Office Production Order projects, and like the COPO Chevelles and Camaros being built for '69, the ZL1 was technically a Camaro option package.

ZL1s were equipped the same as other Camaros of the Central Office Production Order ilk.

ZL1s packed a very special 427-cid V-8, but were basic economy-grade
Camaro inside. ZL1s were the product of Chevy's famous
Central Office Production Order (COPO) program.
The cars began as 396-cid/375-bhp Super Sports with the F4l suspension. Engine and SS trim were deleted, and the cars were equipped essentially as other 427 COPO Camaros, with cowl-induction hood, front disc brakes, a choice of heavy-duty four-speeds or Turbo Hydra-matic, and a 4:10.1 Posi in the strongest axle Chevy could muster. But instead of the iron-block and head L72 427, these Camaros got a 427 called the ZL1.

With its aluminum block, the ZL1 engine weighed a mere 500 pounds -- and produced more than 500 horsepower.

The ZL1's all-aluminum 427 was competition-proven in Can-Am racing.
It weighed a mere 500 pounds -- and produced more than 500 bhp.
It was similar in design to the most-potent iteration of the aluminum-head L88, but it was the first production Chevy engine to also have an aluminum block. It shared the L88's 430-bhp factory rating, but actually had over 500 bhp -- making it likely the most powerful engine Chevy ever offered to the public. And it weighed just 500 pounds -- about the same as Chevy's 327-cid V-8.

The Camaro ZL1 was fully street legal, but its head-turning speed came at a high price: $7,200.

The Camaro ZL1 was fully street-legal, but at a price of $7,200,
it was best suited to professional drag racers who could recoup
some of its cost in prize money.
The entire car carried the full 5-year/50,000-mile warranty and was fully street-legal. With the factory's stock dual exhausts and tires, it turned low 13s; headers, slicks, and tuning got it into the 11.6s at 122 mph. Chevy never built a quicker production car.

All this came at a price: $4,160 for the ZL1 engine alone, pushing the car's sticker to a stratospheric $7,200. Chevy needed to build 50 to satisfy the NHRA, and actually built 69. About 20 ZL1s went into organized drag racing, turning low 10s to set several Super Stock records. Well-heeled individuals bought others, but the high price took a toll: At least 12 engines were removed and sold separately, and about 30 unsold cars were returned to Chevy. It took until the early '70s to sell them off.