C3Paul

Apart from the possible mess with oil splashing, which could be eliminated by customising an old valve cover, what's your opinion?

Using roller cam and hydraulic lifters.

Worth doing?
Any advantage?

Crimson Thunder

I still adjust lash with the engine running although it is hard to hear the clacking over the noise of my side pipes. I just cut up an old valve cover and there is no mess.

530planeman

I use the clips<br/>Bring down slow after clicking stops about 3/4 turn<br/>Wes

71 Green 454

I do mine the same way using the clips.

C3Paul

Sorry, what are the clips?
I have never seen them before.
Do you use them with Solid lifters?

MotorHead

When I was using hydraulic cams I would set the valves cold and then use a cutout valve cover with the engine running for the final adjustment.

71 Green 454

https://www.summitracing.com/parts/mrg-1015

TimAT

If you have any size solid lifter cam that has any real spring pressure, trying to set them with it running will eat your feeler gauge. It'll just chop divots in it.

cardo0

I think adj w/eng running gives me a better feel of when the p-rod can no longer move up & down and just starts to drag. U don't have to figure out if your on the base circle of the cam either.

I have changed to using 1full turn of pre-load now. It actually makes a tiny bit more power due to less plunger travel which in turn takes from the vlv lift. And I never plan to run the motor to high enough rpm for vlv float to occur where a small pre-load like 1\4 or even 1/2 turn would minimize vlv train damage.

Hope this helps - for hyd lifters of course.

cv67

Doing it runing is foolproof

I have a set of feeler gauges I keep around as a laugh someone tried adjusting their solid runniing. Must have fast hands no it dont work.

C3Paul

Would love to see someone swapping feeler gauges for accurate reading

gkull

I have not since I was a youngster set valves on a running motor. I admit that everybodies feel for the ability to still spin the pushrod is different.

In high performance, higher spring, pressure H flat and H roller motors I adjust hot

Rescue Rogers

I do my solid lifters cold, motor off. I have an old cap that I cut the center out of to tell where the rotor is pointing. I found a paper that explains how to adjust a 30-30 cam so that you are off the lobe. Its written by John Hinckley and Duke Williams. Very good info. Makes my lifters quiet

fishslayer143

I have always set mine by feel , first cold , then warmed up and adjusted running to 1/2 turn past zero....BTW, you won t need to do them ever again

cardo0

That's a good point as higher pressure springs may make the "feel" more difficult. But myself I never get into that situation using modest cams and spring. Something to consider though.

gkull

I had 7200 rpm and running up to 155 pound closed 1.46 diameter springs with 200 cc dart 2.055/1.60 valves ported sportsman iron heads on my 355 L-82 bottom end of course balanced and blue printed

lars

There's no good reason to set valve lash on a running engine. I've been around racing and racing engines for over 40 years, and I've never once seen a competent race team or engine builder set valves on a running engine. On the dyno, we do an initial cold lash adjustment to get the engine fired up. Once the engine is up to temp, it's shut down, and the lash is set hot on the non-running engine. Once done, it's done. Same process is used for setting lash in the pits on the race cars - we never set lash on a running engine, whether it's hydraulic or solid.

Danish Shark

Well that's the whole point. If you're not used to adjusting valves then do it with the engine running as it can be difficult for us amateurs to find zero lash, especially if people insist on teaching the spinning method instead of the "moving up and down" method.