THIS.........Works every time and is the non "lazy" better way........

Agreed, never had an issue.

Back in my Chevy days, I set the valves on my new hydraulic cam at zero lash. That was the hot trick of the day. They couldn't pump up because they were already as tall as they could get. I ran the engine for about four years and had no problems.

Now the hot trick is zero lash plus 1/4 to 1/2 turn. The thinking on this is that at zero lash, the little piston inside the hydraulic lifter will pound out the wire retainer. I guess it's possible, my old cam was designed 40 years ago. Valve action is a lot more abrupt nowadays. So use the new advice.

R.

No, I think zero is still the hot ticket, just not on Moparts. Better with a Tru-Arc retainer, but I've run a bunch with std wire retainer too.

Alternatively, if you are running a fast rate cam and the lifter cannot keep up, use a short travel lifter and run it 0.005 off the bottom.

That is a shame they were not setup right from the beginning.

I only set the preload on a hydraulic cam once when it is on the engine stand with the intake manifold off so I can see the plungers in the lifters.

One by one set it for zero lash watching that plunger, then a little pre load on that plunger, down a little ways from the snap ring.

That is the last time you ever you should have to touch it because the lifter takes up any extra slack and keeps everything together smoothly with little to no valve train noise when the plunger is in the middle of it's stroke in the lifter when the valve is closed. A hydraulic lifter is self adjusting once it's preload is set.

Like someone said above, why would you want lash/clearance with a hydraulic cam? and beat all your parts together when running. Even on a fast ramp cam of today like the 274 your running.


I have built countless street motors with hydraulic cams of all varieties and they all lived long healthy lives setup this way.

I think doing it blind with the intake manifold on is very risky cause you can't see what your doing and you can not be sure what that plunger is doing or where it's at in the lifter. Make sense?

To me zero lash is how I would set mine if I was racing the car alot. Cant pump up any more and hold a valve open. I remember that my buddy did that years ago in his 350 Chevelle when he was racing me in my 273 Dart. He missed 3rd gear and just as I grabbed 3rd he fell way back and did not come back to his house for about 30 minutes. He had to wait a bit for his lifters to bleed down since he over reved his eng when he missed 3rd gear and his lifters pumped up to much and held the valves open some.
Course zero lash can be a little noisier also and most manufactors of course want the plunger down about 3/4 turn to take up for wear. Ron

This too.

I've had lifters that are very difficult to "feel". And it takes some time to know what to feel. If it has factory heads, you can see and watch the plunger with the intake on.

If your rocker arms have 3/8 inch x 24 adjusters that have 24 threads per inch then one full turn equals .0416 (I round it up to .042) of travel so 1/4 turn is right at .0105. My message is 1.4 turn is near .010 preload, 1/2 turn is .021 and so on
The 7/16 adjusters are .050 per thread so 1/4 turn is .0125, a tiny bit more
Good luck on getting them where you like it