Reply to "393C Stroker Recommended Cam"

The Manley valve spring is part no. 221432-16 Nextek valve springs (1.90 installed height, 150 lbs. seated force, 0.630” maximum lift; 1.530 inch OD and 0.750 inch ID). Accompanied by Manley 1.535 inch OD x 0.062 inch thick valve spring cups; part no. 42330-16 (0.635 inch ID) and Manley part no. 23644-16 titanium 10° valve spring retainers.

The valve spring seats need to be reduced in height approximately 0.042 inch with Manley’s seat cutting tool part no. 41835 to accommodate taller valve springs (1.90 inch installed height whereas the production height is 1.82 inch) and valve spring cups (0.062 inch thick). Valves with 0.100 inch longer stems are recommended for installation; therefore even though the required additional clearance adds-up to 0.142 inch the amount the spring seats shall need to be machined is reduced by approximately 0.100 inch.

Rocker arm geometry also plays a part in this decision making process, it helps if the rocker arm pedestals are not yet modified. If the have been machined already you will need to stand back and look at the options. I can help. The more a block and or the heads have been machined in the past, the more difficult it becomes to advise what to do via the internet.

In terms of the FI Tech fuel injection which system will you be installing, using their terminology? The easy street system, or something else?