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Rod & Main Bearing Clearance


Alum Rods


Octane Test


Rocker Arm Geometry


1972 Cylinder Head End Bolt Hole Clamp


POLY-LOCK ADJUSTMENT

 

INSTALLED HEIGHT DIMENSION

 

LIFTER BORE BRACE

FAQ - INSTALLED HEIGHT DIMENSION
 

 When figuring out which springs to buy, knowing your installed height dimension is critical. Especially if you want to avoid cutting your spring seats. most shops will tell you it's standard procedure to cut the spring seats. We have found that there are many different springs available, which quite often allows us to avoid cutting the spring seats. if your heads are ported, the roof of the port is directly under the spring seat. you'll want to be careful selecting your springs.

AS YOU CAN SEE THE INDUSTRY STANDARD DIMENSION KNOWN AS THE "INSTALLED HEIGHT DIMENSION" IS MEASURED FROM THE SPOT FACE ON THE HEAD WHERE THE SPRING SITS, TO THE UNDERSIDE OF THE RETAINER WHERE THE OUTER SPRING TOUCHES. YOU CAN MAKE THIS MEASUREMENT WITH A SIX INCH METAL MACHINIST SCALE THAT'S gRADUATED IN TENTHS. YOU CAN SEE IT WELL ENOUGH. MAKE SURE THE SCALE IS STANDING STRAIGHT SO YOUR MEASUREMENT IS TRUE.

WE CAN ALSO AFFECT THE I/H DIMENSION WITHOUT CUTTING THE SPRING SEAT BY USING DIFFERENT VALVE LENGTHS, AND OR CUSTOM RETAINERS. WHICH WE CARRY IN STOCK. YOU CANNOT MAKE THIS MEASUREMENT WITH A PAIR OF STOCK CALIPERS.