[Steve C.]

Not necessarily a recommendation here but conversation why it might be a good idea to speak to the cam manufacture with pertinent information involved.

The previous solid roller cam in my current 505 was a custom from Crower with 292/298 @.020, 260-266 @.050 , about 180/184 @.200 and .4250 lobe lift. With 1.65/1.6 rocker ratio. With it I spent time on the phone with Dave Crower about the combination, it made peak power at 6000 rpm. With that cam if raced and banged on he wanted 240 seat pressure and up towards 600 open. If limited street use only, no racing, and at that lower 6000 rpm then for the most part he said ok to 220-225 seat pressure. So it depends so much how the car is driven and the rpm range.

Later I changed cams to a UltraDyne MSP solid roller cam from Bullet Racing Cams, similar to the Crower but with additional .4300" lobe lift. And also a similar discussion with Bullet Racing about the spring pressure. Interesting to note that fellow also wanted the same 240 seat pressure if raced and limited street use. His recommendation was the PAC-1243 rated 240 at 1.900". Also fwiw, that is the same spring as the Comp 943.

A side note to consider, and related to comments by Paul Carter. He has stated in threads if your heads have a 30 degree valve seat, then the seat pressure should a bit higher. The flatter 30° seat has a tendency to bounce the valve more when closing so more seat pressure should be run.


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