BLP Products has made a serious commitment to furnish the engine builder with high quality components to drive dry sump pumps, water pumps, alternators, power steering, fuel pumps or any crankshaft driven accessory.
A major problem when outfitting an engine with any crankshaft driven accessory, such as a dry sump, is it has to use a long balancer bolt to hold the drive mandrel on. These bolts can range from 4.500″ to 8.000″ long. Special high cost studs and crankshaft snouts are being used to try and combat these problems. Even with this effort, expensive failures are commonplace. When the front drive fails, it usually means an engine failure.
To eliminate these problems, BLP offers a unique design drive mandrel system that does not use a through bolt. A stock length balancer bolt is used. The mandrel bolts to the balancer with three bolts and it is recessed in the rear to clear the balancer bolt head. On the Ford Engines, the mandrel has a centering ring machined in the mandrel. The GM engines use a special centering washer that also holds the balancer on. The centering washer insures that the 1.000″ mandrel snout runs true with the crankshaft.
We wanted the mandrel to be dependable, lightweight and run true with the crankshaft. The mandrel must also accept the popular 1.000″ I.D. pulleys and drive gears currently being used. Mike Laws designed a testing device to spin the mandrel and exert adjustable side load. Extensive testing led to BLP’s final design.
Where the 1.000″ portion of the mandrel starts the radius was increased to .150″. The base of the mandrel was beefed up and a 7/16 X 20 grade 8 bolt goes through the 1.000″ portion and screws into the base.
The following 3-bolt drive mandrels fit the Big Block and Small Block Chevy, and Big Block and Small Block Ford engines. They also fit the Small Block Chevy using a Big Block crankshaft snout. You must use the proper centering washer that is listed. The part number suffix is the length of the 1.000″ portion of the mandrel. The overall length is also listed.