Car Catcher: 1981 Chevrolet Camaro Z28 Yenko Turbo Z

Enthusiasts generally regard the mid-'70s through the mid-'80s as a dark time in the automotive world, and while things weren't great everywhere, there were glimmers of hope. Enter the 1981 Yenko Turbo Z. Turbochargers were coming onto the main scene in a big way, and longtime Chevrolet dealer Don Yenko, a former road racer who had already made a name for himself hopping up other Chevy products, saw an opportunity to bring the Camaro back into the game. Although Yenko never published official horsepower numbers, the turbocharged, 350-cubic-inch V8 in his Turbo Z did achieve a 14.51-second quarter-mile when tested by Hot Rod magazine. Only 19 were made, making this the rarest Yenko Camaro of them all. Find this red Turbo Z on offer without reserve at Mecum's Kissimmee sale January 2-12.

crankwalk SuperDork
11/5/19 3:59 p.m.

I'm interested in how that carb system works. The open air filter isn't in a pressurized sealed box. I can't see from that one engine bay picture but is it a draw through system with a pipe below the carb feeding the intake of the turbo? I'm used to seeing draw through turbos with the carb RIGHT in front of the turbo inlet.

Jordan Rimpela Digital Editor
11/6/19 7:54 a.m.

From an article on Hagerty:

Yenko’s “blow-through” turbo setup for the Camaro put compressed air through the stock carburetor. In contrast, Pontiac’s “draw-through” design pulled the air and atomized fuel through the compressor. Yenko’s turbo made a maximum of 7 psi and did not use a wastegate. A compressor bypass valve, also known as a “priority valve,” was claimed to reduce turbo lag by allowing intake air to go around the turbo under vacuum. Water injection controlled detonation, and a fuel heater under the carburetor was said to prevent stumbling and help keep 50-state EPA compliance.

crankwalk SuperDork
11/6/19 2:13 p.m.

So if it's blow through without a sealed and pressurized airbox and the carburetor was stock and not built for positive pressure, it looks like the charge pipe just blows air "at" the carburetor and I would bet there isn't much positive manifold pressure if any. If the charge pipe is under the carb, how would it measure for that increased air that it wasn't accounting for? Maybe I'm missing it but this just seems like a weird way to do it.