Chevy’s Small Block V8 bears out maker’s guts, glory
GM’s 100 Millionth Small Block V8 engine, a 6.2 litre supercharged LS9, as displayed at GM’s Performance Build Centre in Wixom, Mich.
WIXOM, MICH.—Scrabble. The Mickey Mouse Club. Steve Jobs. The Chevrolet Small Block V8. All of these can claim 1955 as their year of birth.
The Chevy Small Block — the 100 millionth of which was built in late 2011 and which has powered everything from pickups to Corvettte racing cars — was the direct result of some serious “no guts, no glory” efforts on the part of Chevrolet’s newly appointed chief engineer, Ed Cole, and his team who, in just 15 weeks, created a brand-new, then state-of-the-art, overhead valve (OHV) V8 engine virtually from scratch.
Its design was compact and simple by the day’s standards, and its brief development was made more remarkable by the use of new manufacturing processes (green sand casting) and component designs, such as stamped rocker arms.
It certainly didn’t hurt that Cole had played an important role in the design of Cadillac’s new OHV V8 just a few years prior, but it was ultimately made possible by the nearly unprecedented level of support provided by both General Motors’ President and CEO, Harlow Curtice, and Alfred Sloan, GM’s Chairman of the Board.
Their intention was to revitalize the milquetoast, six-cylinder-only postwar lineup of the Chevrolet division with eight-cylinder power, a new chassis, and new styling. This new powerplant was also intended to give the division’s fledgling sports car — the Corvette — some real teeth.
In a daring move, the original 265 cubic inch (4.3L) engine, which became known as the “Turbo-Fire V-8” or “Chevy V-8” (there was no “Big Block” until 1958), went straight from the drafting table to production — there simply wasn’t time to test it.
Little could Ed Cole (or anyone else) know that an engine using his same basic design would continue to be manufactured 57 years later, or that one-hundred million of them would eventually see production. Placed end to end, they’d circle the equator 1.8 times.
The argument could be made that today’s modern, fourth generation, LS-family motor has about as much in common with the original Small Block V8 as the four cylinder in your neighbour’s Honda. After all, aluminum engine blocks, variable cam timing, cylinder deactivation, and reverse-flow cooling systems could scarcely have been imagined back in the 1950s.
Nevertheless, a clear design evolution is obvious, particularly if you consider each generation’s changes and similarities.
Just as in the first Chevy V8, there’s a camshaft in the block and the same 4.4 inch cylinder bore spacing that Ed Cole’s team specified in 1955. Pushrods? Check! (The ’90-’95 Corvette ZR-1’s unique, Mercury Marine-made “LT5” DOHC V8 was the only factory Small Block ever produced without pushrods.) Even the location of the oil filter remains unchanged today from its 1956 position — 1955’s had an external filter.
As for the future? There will be a fifth-generation Small Block V8, and some of them, at least, will be produced in St. Catharines just as the fourth generation is now.
General Motors has already confirmed that the next generation will incorporate direct fuel injection, and pushrods would seem to be a certainty, but the General’s lips are sealed beyond that.
While it’s unlikely to have a 15-week gestation, one safe bet is that it will have 4.4-in. bore spacing, just like its 1955 predecessor.
A frequent contributor to Wheels, Brian Early is a professional mechanic.
Building the 100 millionth motor
I was asked to help assemble the 6.2 litre supercharged LS9 engine that represents the 100 millionth motor, being built at GM’s Wixom Performance Build Centre.
Wixom’s PBC is an unassuming-looking small-scale assembly facility that currently produces the LS3, LS7, and LS9 V8 engines used in Grand Sport, Z06, and ZR1 Corvettes respectively. Each engine built here is assembled from start to finish by one individual craftsman (called Experimental Assemblers), much as would be the case with a Mercedes-AMG engine, or the engine in a Nissan GT-R. Completed motors wear a plaque bearing their builder’s signature. At present, there are just 23 employees in Wixom, 13 of which are EA’s.
This handmade production doubtless aids quality, but it also allows GM to offer new Corvette owners the $5,800 option of participating in the construction of their car’s powerplant. Or, as is the case here, having a production-line novice (but full-time mechanic) such as myself help successfully bolt together a 638 horsepower monster. Sadly, unlike all of the other motors produced in Wixom, which are test-fired (on natural gas) and balanced on-site, this one will never run: It’s destined for a display stand, not beneath the polycarbonate window in the hood of a 330 km/h-capable Corvette ZR1.
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