401 sbc build article

grumpyvette

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http://www.superchevy.com/how-to/en...e=cxrecs&cx_navSource=related-bottom#cxrecs_s

http://airflowresearch.com/articles/article031/A-P1.htm

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.

Arguably the best all-around 23-degree valve-angle, conventional port location, small-block Chevy cylinder head, Air Flow Research’s 195cc Race-Port aluminum casting comes CNC-ported on both intakes and exhausts. The result is a more consistent casting that doesn’t require hand-finishing. The exhaust ports
how a drag-race engine is loaded in the real world when you dump the clutch or load it up against the torque converter. Under these conditions, using 93-octane gas with 36-degrees of ignition lead, the engine churned out a whopping 538.5 lb-ft of torque at 4,500 rpm, and it developed a stout 554.2 hp at 5,900. The animal made over 500 lb-ft from 3,900 to 5,800 rpm, and it exceeded the 400 lb-ft mark through 6,300…definitely as advertised—and competitive with many a big-block! If you want to be the torque of the town, ASE’s complete 401 crate engine, assembled using all-new parts and carrying a 90-day warranty, goes out the door for $7,500 complete, less headers and a water pump

flowed so well that—with ASE’s dual-pattern cam—the best overall power and torque curve was obtained by installing 1.5:1 rockers on the exhaust side to complement the 1.6:1 rockers used to open the intake valves.

The heads are fed by a Holley 750-cfm double-pumper carb atop an Edelbrock RPM Air-Gap intake, while an MSD distributor and Champion RC12YC plugs (gapped at 0.035-inch) ignite the spark. You’re on your own for headers, but ASE recommends 13¼4-inch primaries with 3-inch collectors, which is what it used to dyno-test the prototype assembly.

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notice the similarity to the crower 00471 hydraulic roller which in my experience has always produce a bit better power

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http://garage.grumpysperformance.com/index.php?threads/tbucket-engine-project-dart-shp.3814/

yeah! most of the better engine builders have found very similar 383-406 sbc combos, that produce a very good high torque engine for street/strip use, you can,t help building a rather similar combo, if that basic combination of similar components is well know to maximize the basic engines power curve in the rpm range your looking to duplicate!
the key is decent flowing heads, within a certain port cross sectional area and known flow range, a low restriction,dual plane intake with a decent carb, and and a hydraulic roller cam with similar duration,lift and lsa and compression.
sticking with what is a proven combo that works
 
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