Okay, I've searched, read and asked a few members... but I still don't understand it all.

I have an adjustable pushrod length checker, its adjustable from 6.5 to 7.5 inches. I just don't really know what to do with it now.

I have heard that you can use your existing hydraulic roller lifters with a checking valve spring, and then set up proper geometry.

I also heard you cannot use a hydraulic roller lifter; you have to get a solid roller and use that to figure out the correct length and geometry. Then you have to compare the solid lifter to your hydraulic lifter to make sure the height is the same on both, if it's not then you have to make adjustments according to the height difference, and you have your pushrod length. How do I find out what the height difference is though?

I'm getting pretty confused by all this. Anyone know what the correct method is? Anyone have any advice?

 

MW,

When I mentioned the valve checker spring probably wouldn't work, is because your lifters are dry.. no oil inside to keep the lifter from compressing..besides, like I mentioned it'd probably be easier to pull a few lifters than springs.

 

So I need to find a solid lifter, and figure out the height of my hydraulic lifter compared to the height of the solid lifter...

So I need to figure out the height of my hydraulic lifter... this is gonna be fun!

 

Not just the OD, but where the PR sits into the plunger to the roller.


Someone has to have the number difference. Or you have to measure with a caliper for the overall OD, then use the end of the caliper as a depth-mic to see if there is a difference where the PR sits.

You'll get, just don't rush it

 

My lifters are Sealed Power HT2148... I guess I will try to find a solid lifter that I can find specs on, so I won't have to figure out how to measure it... and hopefully I can find height measurements on my lifters.

I know I'll get it eventually, I'm just kinda confused. Thanks for talking me through it.

 

Are those just a factory style replacement?

 

Yes, stock style replacements, just made by speedpro.

Maybe this will be easy if I just get specs on the solid I get.

 

Yes, that would be a plus, but youo also need to know the seat depth too.

i/e say both lifters (hyd and solid) top to roller are 3.25 inches, but where the PR sits (seat) on one is .100 lower in the lifter body...that's important in calulating the correct PR length based on the contact patch.

 

I guess i'm gonna have to get my hands on a solid lifter, and a caliper, and figure out how to measure it out... then i can work from there. Still gonna stop by the machine shop, he might have a solid lifter he can give me.

 

Get two of the same, one for intake and exhaust.

 

Found an interesting article here...Carcraft Article

It explains a bit about the whole rocker arm geometry/pushrod length thing.

It doesn't mention anything about using a solid lifter or anything though. It also uses the method that Comp Cams suggests for correct geometry, which I have heard talked down a bit on the boards...

I will continue to search on the net for more info.

 

Make your own solid lifter by taking apart an old hydraulic one, removing the guts, and shimming the inside. I want to say the cup drops .030" when the valve is adjusted. Insert modified lifter and spin engine after marking valve tip.

The method posted in the carcraft article will get you very close. Remember that most pushrods are available in .025" increments, so unless you're having them custom made, start at the stock length and increase or decrease in .025" increments to get the one that is the closest. If you used a modified lifter with a real spring on the head, your goal is to get the contact pattern centered on the tip of the valve. If you use the carcraft article method, the contact pattern should be about 1/3 of the width of the valve stem and centered, which means when on the base circle the mark on the tip should be about 1/3 of the way in from inboard of the valve tip (intake side). Look at the last pix in article (comp cams illustration).

 

So in the carcraft article, they are basically saying go ahead and use a regular hydraulic lifter? or am I taking it wrong?

I don't have another lifter to modify right now, but again I think I am going to stop by the machine shop and have a talk with him, see what he reccomends, and if he can hook me up with either a used solid lifter or a used hydraulic lifter, which I could modify.

 

They set the valve lash with the stock lifter and "wiggle" the rocker to get the witness mark.