[Fot] Push Rod Length & Mid-lift

[Larry Young]

Greg and Duncan are correct.  A reground cam will undercut the base 
circle and this will take you in the other direction by the change in 
the base circle radius.  For the ones I've measured the base circle 
radius shrinks about 0.10 inches for the typical TR4 racing cam.  This 
compensates for that much milling.  If you use a new blank, you can 
reduce the amount of undercutting.
Larry

>
> On 12/19/2013 10:45 PM, Greg And Alison Blake wrote:
>> Don't forget that if you are using a stock cam that has a race grind, 
>> you have
>> changed the bace circle of the cam. That too will affect push rod 
>> length.
>>
>> Surely Larry Young will chime in.
>>
>> Greg