Small block Chevys were designed from the get-go to be revvers. Light weight and a short stroke/large bore design let that first 265 cubic inch engine make good power up to about 5,000-5,500 RPM—unheard of in 1955 when flathead Ford V8s ran out of steam at three grand or so.
Today you can build a small block Chevy to make power well beyond 7,000 RPM with the right parts. One of the secrets to a high-RPM small block is reducing rotating assembly weight. A lightweight assembly can spin faster, so the engine can hit its powerband quicker. It also takes less horsepower to rotate, so you gain back some extra power.
A lightweight rotating assembly also improves the car’s acceleration and deceleration. That last point is a big plus in circle track racing as faster deceleration in the turns means you don’t need to hammer on the brakes as hard.
A good place to start your rotating assembly’s diet is with a Scat Excalibur Lightweight Crankshaft. Forged from 4340 steel, an Excalibur crank weighs just 48 to 50 pounds depending on which you choose. The cranks are precision-ground, heat-treated, and nitride-hardened for superior wear resistance. Other features include:
• Rough-balanced to 1,800 grams, within +/- 2 percent
• Lightening holes in all rod journals to reduce weight without sacrificing strength
• Large radius on all journals for added strength and wear resistance
• Straight shot and chamfered oil holes eliminate burnt bearings by increasing oil flow from main to rod bearings at high RPM
• Scoop-type main oiling holes force-feed oil into rod bearing oil feed holes
• Bull nose counterweights mean less oil windage in the crankcase
Scat Excalibur Lightweight Crankshafts are available in these configurations:
• 3.480” stroke, 5.700” rod, 350 mains, internal balance
• 3.480” stroke, 5.700” rod, 350 mains, front internal/rear external balance
• 3.750” stroke, 5.700” rod, 350 mains, internal balance
• 3.750” stroke, 5.700” rod, 350 mains, front internal/rear external balance
• 3.750” stroke, 6.000” rod, 350 mains, internal balance
• 3.875” stroke, 6.000” rod, 350 mains, internal balance
• 4.000” stroke, 6.000” rod, 350 mains, internal balance
• 4.000” stroke, 6.000” rod, 400 mains, internal balance
