OEM Regrind 264/272 Cams- Less lobe height than stock?

[JusMX141]

I had a set of Re-grind OEM cams here at my shop that came out of a customer's 1G when he upgraded to a set of Crower 64413's (272's).

I did a little comparing last night, and was shocked when I found that the lobe's total height on the Re-grind cams was .005-.007" LOWER than the stock cams that I had sitting here. Is this normal?

I know there are variations in lobe height between certain OEM cams depending on the number cast into them...the stock (uncut) cams had "A" cast into both the intake and exhaust, while the Regrinds had "I" on the intake and "B" on the exhaust. When compared to the brand new Crower cams, the lobes on the Crowers were about .003" taller than the stockers, while the regrinds were .005-.007" shorter than stock.

I was just concerned about how much this would effect overall performance. Obviously the lift and duration were altered as the car they came from had an aggressive idle, but is lobe height really that important?

 

[Defiant]

See if the base circle is shorter as well. The usual method of making higher-lift on a stock cam is to make the whole circle smaller, which gives you a higher effective lift. This saves the cam grinder the the expense and labor of either welding-up the lobs, or starting with a blank billet (what some cam shops refer to as "doing it right").
Because of this shortcut, re-ground cams often don't have as good a design as stock cams, and wear out faster.

 

[99redgst]

Adding to Defiants info, sometimes shims are used under the lifters to compensate for the material removed from the base circle. Not sure if you checked to see if there were any installed with those cams, and I'm not sure if there would be any detrimental effects from leaving them in after installing different cams. I have never personally used regrinds myself.

 

[turboglenn]

I"d definately pull the lifters and look for shims. I have the DKS/FFWD 264/272 combo and had to put in shims. If you were to not take them out you would either be running your lifters bottomed out or having valves that won't close all the way.

I love my regrinds, but maybe that's because i got 2 for the price of one "real cam"

EDIT: and yes, the whole lobe gets turned all the way around, making the base cirlce smaller effectively raises lift and duration while the cam still seems smaller. It's the measure at the lobe from fully closed to fully open and how long they're open for that determines the 264,2724 etc..

 

[T9S1i]

i put in dks 264/272 and didnt need the shims. We checked when we installed em and there was no slack or play inbetween the lifter and cam.