CAT steel main girdles are machined from 1045 medium carbon billet steel. Surfaces are finished on CNC machines for accuracy and are zinc anodized for rust resistance. Package includes 5140 high strength studs and washers and are recommended for racing application.
In an effort to reduce costs and save weight, auto manufacturers started using weaker engine block castings as early as the late 1970’s. The were able to do this without problems thanks to increasing smog regulations causing decreased horsepower ratings. While these blocks hold up just fine when putting out 220 horsepower, they cannot go racing. A main support helps to “beef up” your lower end by reinforcing the alignment of the main caps. The webbing on these blocks has much to be desired and a main support helps stregthen this area of weakness.
ISTALLATION NOTES:*Make sure to have 0.020" minimum clearance between main cap cetner top and girdle cross. Insert washers under girdle to increase clearance if need.
*Place oil pump on block with hand tight to ensure the pump shaft is clear from girdle. Grind off obstructed frame on girdle if need.
*Hand crank engine to ensure all rods and pistons are clear from girdle. Grind off contact area if need.
*Make sure the oil pick up stick is clear from the girdle.
*Torque main bolts with moly lube on thread from cneter bolts to end and follow torque specification:
7/16” bolts with 65 FT-LBS torque.
1/2" bolts with100 FT-LBS torque.
7/16” studs with 60 FT-LBS torque.
1/2" studs with 95 FT-LBS torque.