[big block fiero]

David vizard, I have a 500 ci cadillac engine in my fiero that is the very first such engine to succesfully have the variable displacement v-8/6/4 feature. The mechanizm that turns the valves on and off does so wile the lifters are riding the base circle. there is almost .015 movement in the mechanizm that is nessesary to unlock a shutter. The hydrolic lifter does'nt steal this .015 clearence because there is a secondary spring inside the mechanizm that is of a bit less pressure then the seated pressure of the conventional valve spring. I am having a cam cut with a .012 base circle runout variation so the lifter can steal this .012 then preload the mechanizm before the cam ramp arrives so I can regain some lift that was lost by the mechanizm and prevent valve bounce. Do you know, are there cams ground this way for variable displacement applications such as mine that I could look to for validation of my concept for increased rpm and horsepower?

This multi-purpose engine is a performance with economy sleeper with the engine hidden and the car appearing stock. This valvetrain has roller rockers with stud support tie bars that are hidden and fit under stock valvecovers. Power is delivered thru a switch pitch turbo 425 so the car can sound like a stock 4 cylinder then switch to an 8 cylinder with stall converter.

Matt kneen mpls, mn.