Tuesday, April 5, 2011

To build or not to build...
The geometry of Chevy’s 283 shows why small-displacement V8s aren’t always the “best” option
Today’s hot topic of discussion in the world of high-performance is whether or not a Chev, 283 small block is still a valid platform for a hi-po motor build. My general rule of thumb when it comes to engine building is that small-displacement makes for sky-high revs, but torque and bottom-end are often sacrificed in this process, and so a paradox exists within the science of engine-building.
The question was one of how a small-displacement, Chev V8 could be built to run with bigger motors, like a 327 or a 350. A February, 2009 issue of Car Craft admits that the 283’s 3-inch stroke is perfect for building a high-winding powerband. Car Craft further points-out how former Corvette engineer/designer Zora Arkus-Duntov, during his time with GM, headed many development projects and ran many parts-refinement programs to offer more factory and aftermarket accessories for the 283 block, paving the way for Chev small-block performance.
Another enthusiast forum, ChevyTalk, counters Car Craft’s adoration of the 283 motor, observing the small engine’s restrictive valvetrain geometry, only allowing for a 1.94/1.6 valve combination. The other flaw of building a high-output 283 is that not all 283 blocks can be bored 0.125,” or 1/8th of an inch over. What this all boils-down to is that even to punch-out a 283 to a 302 requires retrofitting a 327 crank into a 283 block, or vice-verse, which means that it’s a lot more worthwhile to hop-up a 327 or a 350 motor, if a conventional small-block build is what you’re after.
Otherwise, building a hi-po motor from a 283 block is pretty much useless in today’s performance market. In fact, the only reasons why an enthusiast would want to do a performance-build on a 283 nowadays is to maintain a sense of “vintage” when building a car. Otherwise, Chev’s 283, when built with the right performance accessories, is mostly useful in oval-track and other high-endurance applications. But even with a slightly-more cubic-inch laden motor like the 302, the broad, high-winding powerband is insufficient for normal, low-RPM driving conditions.
- Sal Alaimo Jr., B. A. (4/5/11)

S. J. A.

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