Measuring camshaft lift
 

If I measure the diameter from heal to nose and then at a right angle to the first measurement ( the narrowest) will the difference be the lift?

Re: Measuring camshaft lift
 

Re: Measuring camshaft lift
 

Re: Measuring camshaft lift
 

I'd say, measure from the center of the cam to the highest point of the lobe, then measure from the center of the cam to the center of the heel.
Subtract the LITTLE number from the BIG number, and that's the LIFT!
There's probably a FORMULA, but I don't know it????---A dial indicator would work, also.
Bill Slightlystupid

Re: Measuring camshaft lift
 

YES, in the case of a model A Ford original cam.
They were of the 3 arc design so the base circle is concentric.
There are no clearance ramps.

Re: Measuring camshaft lift
 

#2 says No

#5 says YES

???????

Re: Measuring camshaft lift
 

Go with #4. Dad knows his shit

Re: Measuring camshaft lift
 

Just a week ago I mounted an A-grind cam between centers in my lathe and used a dial indicator to measure (accurately!) the lift.It was the same as when measured as the OP described.

Did the same with a B-grind and the difference in lift was OTOO .050", the same as using the OP's method.

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Re: Measuring camshaft lift
 

Hey Mike,
If you do not know Pete, then I understand your question.
Your answer is....Pete is a 50 some years of experience as...... CAM MAKER :) !

Pete builds and races cars and engines also.

There may be another here on this board, besides Jim B, who knows cams, but I would not question Pete's credentials where cam knowledge is concerned.

Re: Measuring camshaft lift
 

I was able to just catch the edge of a valve with my one inch travel indicator thru the spark plug hole. With the spark plugs out and car in high gear you can slowly move the engine. Zero out the indicator with the valve closed then push car slowly and you will see the rise and fall of the valve and lift. Mine was .287 lift which is correct for a stock cam with proper lashed valves.

Re: Measuring camshaft lift
 

Question: if your lift is , say 305, then is that the lift before the lash is subtracted or the total of the lift and lash.?

Re: Measuring camshaft lift
 

I like pictures,

http://www.lunatipower.com/Images/Te...eLiftSmall.gif

http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx

Re: Measuring camshaft lift
 

I like pictures too.
Here is a drawing showing clearance ramp locations that will clearly interfere with attempts at measuring the base circle 90 degrees to the lift.
http://www.team-integra.net/images/B.../tuan/lobe.gif

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I "think" I once read that CLEARANCE RAMPS had something to do with using HYDRAULIC LIFTERS????---"Maybe" I'm just confused????
Bill W.

Re: Measuring camshaft lift
 

Checking on the master cams for 3 of the most popular street/touring grinds for the model A/B, there is no difference in lift as measured with micrometers or a dial indicator.
In other words, the clearance ramps start above or at the center line.
However, as the grind becomes more radical as in a drag race or circle track grind, this does not hold true. this is primarily because the base circle becomes smaller.
The readings can vary as much as .002 to .005.

For Bill W, the base circle on a hydraulic lifter cam is concentric.