Hey guys, how are pushrods measured? The reason I ask is because I am measuring a set of Trick Flow pushrods that are 7.150" and some stock length pushrods. For the TF set I am coming up with 7.165" and stock I'm getting 7.186".

So I'm wondering do you just measure the overall length or what? I can't make any sense of these measurements.

I'm using a Mitutoyo dial caliper to measure. Just so you know, I work in a Metrology lab so I know how to use the measuring equipment .

 

Here is how to get the correct PR length . . .

The following is a method of verifying proper valve train geometry. After you have estimated the required pushrod length using a Pushrod Length Checker, use this method to verify that the valve train geometry is correct (using the rockers you are using in your engine):



1
The first step is to install a solid lifter and an adjustable pushrod. Mark the tip of the valve with a marker



2
Install your rocker arm and set it up with zero lash.



3
Rotate the crankshaft clockwise several times. Remove the rocker arm. The contact pattern of the rocker tip will be where the marker has been wiped away from the valve tip. The pattern should be centered on the valve tip, and as narrow as possible. If it is not, experiment with varying the pushrod length to yield the best pattern.



4
Pushrod Too Long: Notice how the pattern is wide, and shifted to the exhaust side of the valve tip.



5
Pushrod Too Short: Notice how the pattern is wide, and shifted to the intake side of the valve tip.



6
Pushrod Length Correct: Notice how the pattern is narrow and is centered on the valve tip.

 

No, no, no. I know how to get the correct length for the valvetrain geometry. I am trying to measure the physical pushrod.

 

I use a 8" digital caliper. Piece o' cake.

 

ah.. guess I should have read the rest of the post. Don't know how I missed it..... I would think end for end is what you are measureing. That would be the length.

 

Okay let me rephrase the question.

Do I just measure the PR end to end or what? Because I am doing that with a set of TF 7.150 and I am NOT getting that reading. I am getting ~.015" longer.

 

Check this out:

http://www.compcams.com/Technical/FA...nGeometry2.asp

Look at the diagram at the bottom of the page. I think this is what you are
looking for.

 

Yes thank you!!!