1954 Sorrell-Manning: Hot Six-Carb GMC Straight Six Under Sexy Early Fifities Fiberglass Roadster

(first posted 12/18/11)   This Sorrell-Manning Roadster from 1954 is utterly stunning, and if someone had told me it was a special-bodied Aston from Italy, I’d have been convinced. Bob Sorrell was an exceptionally talented designer/builder during the fiberglass golden era, and his SR-100 roadster was not only his earliest, but quite possibly the finest. Only seven were built, and this particular restored one has a period-correct 331 Chrysler hemi under the hood. But the first one he built especially for a Car Craft cover article, had what has to be my favorite vintage six, a 302 GMC bored out to 320 inches, and sporting an aluminum head and six carbs. Straight six porn indeed.

But before we get to that engine, let’s just savor what Bob Sorrell created here. Truly stunning, especially for 1954.

Here’s another angle. These two shots are from conceptcarz, that has a full gallery.

Now to the original and the Jimmy six. forgottenfiberglass has the full article, a reprint from the 1955 Car Craft magazine. The six exhaust pipes are already somewhat visible form this shot.

Here it is fully revealed.  The GMC truck sixes were very popular hot rod material in the early fifties for a couple of very compelling reasons: they had over head valves, large displacement, and very easy to come by, having powered untold thousands of WW2 trucks as well as civilian versions. The new ohv V8s were just coming out, and not easy to come by. A Jimmy six easily put out more power than a Ford flathead, especially in the state of modification this one was in.

This one is sporting a Fisher-Horning twelve port aluminum head, a one-eight inch overbore for a full 320 cubic inches, 8.5:1 compression, McGurk billet cam, etc. And hanging on to the intake side are no less than six Amal carburetors. The engine was never dyno tested, but the owner said “It really scares you when you get on it”.

BTW, this gem sits on a Kurtiss roadster chassis, very similar to those used for Indy cars at the time. Ditto for the magnesium Halibrand wheels. Vintage perfection.