[roadrage david]

Here is what Crane hase to say ::::.... Oil Ristrictors- Here at Crane, we do not recommend running oil restrictors becuase of the fact that you wil starve the top end of the motor.This lack of oil will not allow the components to be lubricated or cooled by the flow of oil,witch it desperatly needs to remove the heat created frompressure and friction. Thisin turn will create excessive wear and shorten the life of the springs, valves, guides,rockers and lifters,ect . On our shaft Mount rockers, oil is a necessity to the longliovety and life of the bearings . So, if you have to run oil restrictors , you must open up the restrictors to .100? to insure that you are applying enoughf oil to the rockers.

[TEMPERMAN67]

I've talked to a lot of friends of mine running pontiac motors in the 10's with no restrictors at all. With no problems at all. As you said the springs and valvetrain need to be cooled as well.

[taff2]

I use restrictors in the lifter bore oil holes (about 0.030" ), on a solid flat tappet cam, these still allow quite a lot of oil to the top end,no problems so far up to 7000rpm useage.

[roadrage david]

now i realize everybody things 1/4 mile but what about long distence high speed crusing and ore road raceing??..........

[77TA]

Everyone I talked to back when I was asking this question years ago said for a around town mostly drag car it was ok , but plan on replacing springs yearly if you drove any miles and sustained driving such as a daily driver would result in spring failure. fwiw

This was with the typical .030 sized restrictors I was asking about referenced in all of HO racings books for solid cams..

[roadrage david]

ok !! im planning on driving it for longer periods of times . only sporatic 1/4 races. but mostly long distance high speed ralieghs..