It’s been said that “Horsepower sells engines, but torque wins races.” There’s no question that a broad torque band makes for good street performance and driveability. An engine with more cubic inches has greater torque potential than a smaller-displacement engine, and assuming similar overall displacement, a longer-stroke engine generally develops more torque than a short-stroke mill. That’s why for many years Chevy’s 400ci small-block—with its 4.125-inch bore and 3.75-inch stroke—was the choice for car crafters looking to maximize torque in a relatively compact, lightweight package. Unfortunately, used 400 cores are getting scarce. While the as-delivered 4-inch bore on GM Performance Parts’ Bow Tie block can be overbored to 4.125-inches, the General charges premium prices for these premium blocks. What’s a torque-hungry small-block lover to do?
Enter American Speed Enterprises (ASE), specialists in building powerful but cost-effective Chevrolet engines for the masses. With the advent of affordable 3.875-inch forged stroker cranks and 6.0-inch rods, ASE owner Gail Trent has developed a 401ci small-block Chevy package built around a Mr. Goodwrench service replacement block (PN 10066034). Trent says these blocks have thicker cylinder walls than standard production blocks built in the last 25 years, so they readily accept a 0.060-inch overbore.
Even though a long stroke is good for torque production, traditionalists argue that a long-arm crank makes for a lazy engine upstairs. ASE fixes this with lightweight reciprocating components. Typical Chevy 350 bob-weights are in the 1,910-1,930–gram range, but on its 401, ASE holds bob-weights down to only 1,577 grams. The engine makes power past 6,000, and is internally balanced without Mallory metal.