Back to the valvetrain...

[mrltd]

OK, make sure I'm doing this right.

Stock pushrod length= 6.270
Preload= .030

Awhile back I did a test fit of the adj rockers. Not enough adjustment. So, from that rocker I figured that the pushrod needs to be ~.20" or so longer to put the pushrod cup in a good spot in the rocker.(I have the adjustable pedestal ones, the cup is hieght adjustable)

So, I will need a pushrod that is 6.270+.030+.2= 6.500" Correct?

The least expensive pushrods that were the closest in length were 6.480 for 80 bucks. There were 6.500" exactly. The least expensive 6.500 was 87 bucks...Meh 6 bucks....

[Mercracer]

Truly good spot on the rocker can only be adjusted by pedestal height. If you are only referring to zero lash with .20 more length, then that is something different. Don't forget the rocker ratio. If it takes .20" length to get you zero lash, then you need .030" more lifter preload, you only need .019" more length with 1.6 rockers and .018" more length with 1.7's.

[mrltd]

Yes, .20 to get zero lash. That .20 is without any preload. That's why I fatored that into the needed length. Is that correct?

[mrltd]

mercracer???

[Mercracer]

If you measured .020 on the valve side, then you need less on the pushrod side depending on the rocker ratio.

[mrltd]

No, I measured it on the pushrod side. The pushrod cups are adjustable on these rockers...

[mrltd]

I bought the rockers hoping for them to have enough adjustment, they don't. The cup has to be so far down that there isn't enough thread for the locknut to grab safely.

What I did for measurement was install the rocker and ran the adjuster all the way until it hit the pushrod. Then I measured how far the adjuster was out from the base of the arm.

[mrltd]

these are the arms....

[Mercracer]

Double check it by setting the adjustable cup at a loose setting and take up the pushrod lash and then use a feeler gauge and check your valve lash. See if your numbers agree.