PDA

View Full Version : Lifter adjustment -- new cam.



914Driver
11-20-2009, 10:49 AM
I'm installing a new cam with bigger lift and different duration. The manufacturer suggests Summit push rod # _________ . Once installed and assembled how can I be certain all is well?

On other cars with hydraulic lifters you put in shims of varying thickness to get the specified play. How is it done on a 3.8 with roller lifters?


Dan

mywhite89
11-20-2009, 11:38 AM
Once you have the cam in you'll want to get a push rod measure tool so you can measure what length you actually need at zero tolerance from the rocker to the lifter without pushing the lifter down at all. then you want to add pre-load measurement for the hydrolic lifter to the original measurement and order as close to that total number as possible. I can't remember from the top of my mind what pre-load is recommended for our lifters though. The figures should be available though.

mywhite89
11-20-2009, 12:25 PM
when it comes to shims, you would have to shim under the rocker pedestal. I don't recommend shimming much if any if you can help it. The more you shim the less structure you have to hold the pedestal from twisting. When I did mine, they were so close, I didn't find one that I even needed a .015 shim, so I didn't shim.

Mike8675309
11-20-2009, 02:08 PM
I'm installing a new cam with bigger lift and different duration. The manufacturer suggests Summit push rod # _________ . Once installed and assembled how can I be certain all is well?

On other cars with hydraulic lifters you put in shims of varying thickness to get the specified play. How is it done on a 3.8 with roller lifters?


Dan

whoever you bought the cam from should be able to help. If not an actual cam vendor, or shop, then you will probably have to measure for either custom push rods, or shims, or both.