If one power-adder is good, wouldn’t two be better? Seems obvious, and for those who haven’t followed along, Car Craft has tested a Vortech S-Trim supercharger and nitrous oxide separately on a ’91 Camaro Z28, but never at the same time. In order to get these two to work together in the same engine without driving over the crank, we decided that an upgrade from a stock 305 with cast pistons was necessary. During the search for a suitable 350, Gail Trent at American Speed convinced us that the low cost of small-block Chevy stroker cranks makes a 383 hardly more expensive than a similarly built 350, but capable of putting out a ton more torque. We bit.
American Speed’s stroker crate engines include heads that are compatible with factory Tuned Port Injection manifolds and a one-piece rear main-seal block that accepts a roller-style camshaft, like those found in ’87-and-later Camaros and Corvettes. As with all American Speed engines, the 383 was dyno-tested before it was shipped. It made 418 hp on its break-in run with Edelbrock injection.
We’ve got to give a big thanks to the guys at American Speed for helping us through this project. As the parts arrived and the project took shape, Gail had to deal with all the phone calls (two a day for a while) and misdirected mail. We bled, our friends bled, and the swap took a lot longer than anticipated. The engine swap and an unexpected intake-manifold debacle took the entire Fourth of July weekend including at least one overnighter. Some people got coleslaw and dogs; we got Del Taco at 3 a.m. and a phone call or two at the shop from family and friends wondering if we were still alive.
So why do it? The results were more than worth the effort: almost 500 ponies at the rear wheels, and the engine is nowhere near its limits. With only 8 pounds of boost and a measly 50hp shot of nitrous, the power-adders are barely even screwed on. A Vortech T-Trim blower to provide more boost and a little more spray would put 575-600 rear-wheel horsepower within reach. Moreover, it’s mellow, streetable, and inconspicuous. Truth be told, which it is, it was also ungodly expensive. But it still rocks.
