I was reading the CRG article on setting the valves. It says for stamped steel rockers only in article. I am going to put some 1.5 roller tip rockers on my engine. I can't see why you would set them any differently. If its a true 1.5 I am thinking you set them at .029 cold. Opinions?


http://www.camaros.org/302valves.shtml

Joe..I did not read the link...but the cold lash is safe for start up.Obviously you will run the lash when the engine is up to operating temp to compensate for thermal expansion with different materials and components.

i 2nd that

We always set the 30 30 cam when hot.

Set them cold fire it up and let it warm up, then check the lash again. Once you have your cold lash figured out you won't have to mess with them hot again. I can set mine cold fire it up and it is right on the money when warm. Head material will obviously effect how much the lash will change from cold to hot.

I didn't read the article either, but it doesn't make sense that you would have to adjust the lash any different because of the rocker type. Maybe they are taking into account that the material of the rocker is going to effect the lash once it warms up.

If you search Crane Cams website they have an article that gives specs on how much to adjust cold lash for the different block/head materials. For me it was right on the money.

When you say you are setting them hot, does that mean the engine is running with oil going everywhere? Or the engine is warmed up, shut down, valve covers removed and then you go thru the valve adjusting sequence?

alan

I always wondered about that "hot and running"

You don't set or check the lash with the engine running. It's not possible. When they say hot last that means the engine is up to operating temperature, but the engine is shut off. We are talking solid cams here, which means using a feeler gauge to check the gap (lash), with the cam on the base circle of the valve/lifter being adjusted.

Now with hyd. cams (which have pre load, not lash) you can do it with the engine running.

Two different animals though.

You CAN set them hot and running, but it is not advised and not that accurate.

For initial setup I would set them 0.028 cold and then bring it up to temperature. Then check again after engine is "hot" - but not running.

OK, thanks for the clarification. Isn't the fact that it is called the 30-30 cam related to the fact that lash is .030" on both exhaust and intake? Doesn't the CRG recommend .024"? My cam was lashed on the tight side and the idle was somewhat undependable. Vacuum reading were crappy too. When I re-lashed it to .030", the idle settled right down and the vacuum went up to 9-10". The idle has been rock solid ever since.

alan

With 1.5 roller rockers, a setting of 0.028 cold should end up close to 0.030 hot. If not, adjust the cold setting to compensate.

How are you going to get your feeler gauge under the tip of the rocker with the engine running? If you're not going to use a feeler gauge what method are you going to use to measure the lash with the engine running?

How can you state what to set the lash at cold without knowing the cylinder head material?

No problem. Been doing it that way for 35 years. But I also said "not advised and not that accurate."

If you will read carefully, I never said it would be EXACT. I said "close to 0.030 hot. If not, adjust the cold setting to compensate."

Come on, this is not rocket science.

Not rocket science at all. I just wanted to know how anyone would adjust a solid lifter cam with the engine running. Still want to know how you do it, I love to learn new things. If you are going to make an adjustment to begin with why wouldn't you want it to be accurate?

I have never seen anyone adjust lash on a solid cam with the engine running. I have never personally done it either and don't see how you could. I set mine cold, warm the engine up and double check, once you have an engine down, then you don't need to worry about hot lash. Check them cold and you don't have to burn your hands or drip oil everywhere.

When a guy asks a question like this they usually want the "correct" way to do it.

Hi Royce..alls well I hope with you.
Setting solids running takes me back to the mopar dealer circa 1978 straight out of high school.
Slant six 225.Still have my .010"/.020" feeler gauges I purchased new 33 yrs ago.
Setting lash running was the preferred method both in the shop and by the fsm.It was part of our regular maintenance tune up and I enjoyed it.You could hear and feel the engine respond to minor tweaks and watch the vac gauge rise and level off.The feelers you had to move in and out quickly while the box end 3/8ths wrench in your hand rode up and down on the pushrod side.
By all means..not what I do today on my bbc,I use the same method you do.The little slant six would idle down to 400 rpm and not sling oil and the feely factor was similiar to static settings.
Just saying..this thread took me back in time.
Take care Royce.