I walked into my pal John Barkley's garage one day a few months ago and found him hovering wrench in hand over a small-block Chevy short-block-not an uncommon occurrence as Barkley is a lifelong drag racer and SBC aficionado. At that point I assumed he was assembling another one of his race motors, but when I asked what he was up to, he explained that he was freshening up an early pre-smog engine, a vintage '64 327 in fact-and he seemed pretty excited about it too.
Not being a real engine guy (to me a rebuild usually consists of degreasing and repainting) I asked if he was building another race motor. "Nope, I'm just freshening up this old 327 I yanked out of my '57. These older pre-smog motors are getting pretty rare, and because of the smog laws some states have on the books, it's a perfect engine for a street rod or classic pickup as its casting numbers are unique to that era. This one has about 20,000 miles on a complete rebuild so the bottom end is in great shape. But being such an early engine it has a pretty stout compression ratio (10.0:1) and the early valvetrain required leaded fuel to help lube the valve stems and guides-that's two strikes against running it on the lead-free fuel we're stuck with these days. So I thought I'd just update the top end-in the previous rebuild the block was bored .040-over and the new slugs sit about .040 or .050 below deck height. That reduced compression a bit and the new RHS Vortec-style heads I chose have a larger chamber (64 cc versus 60 cc) than the stock ones so that drops the compression into a more lead-free fuel-friendly range."
Photo Gallery: Upgrading A Small-Block Chevrolet Engine - Classic Trucks Magazine
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