Reply to "Rocker stud got loose, again"

Originally posted by SF:
"Follow up
This is what I have come up with
1) When I set up the valve spring and checked for coilbind I have to change springs and go for offset locks. This would result in less open spring preassure..."

Yes but you need to measure it with a spring pressure tester to determine an exact number. Your offset lock is probably .100". I doubt you can measure the difference in spring pressure. It is probably something very small like one pound? I wouldn't worry much about the difference in spring pressure with just that change. Don't bother.


2) I have probably set the lash hot on cold. Since I have an engine with both the block and heads in aluminium the hot lash would have been .034 hot...

Setting it cold with the engine not running is more accurate. Just extreme hot or cold air temps should be avoided. Scientifically 70 F is the standard air temp for just about anything I can think of?

3) Or a combination of both

No forget about a combination. It is either hot (with the engine running) or cold.

Now I have set the lash cold to .014 which will theoretically give .026 hot (target), right?

If CompCams said to deduct .012" when setting the lash cold from the desired hot lash setting to arrive at the hot setting, then yes, you are correct. Did you check with them?

Roller rockers suggestion?
I think I will go for a new set of rockers though those I have don't feel ok at the roller tip.
Steel or aluminium rockers.

I personally like the new CompCams "chromemoly" rockers but I have only seen them in 1.7 ratio instead of 1.73. Aluminum arms, even the best ones are not as strong as these.


As described above about open pressure;
Is there any advantage to change valve locks with zero offset to reach a higher open preassure and go for a rocker with less gearing, 1:6 insted of 1:73?

That's two questions. No pressure advantage on the lock offset but make sure that the valve stem tip is long enough to accept them and not have the rocker arm bottom out on the top of the spring retainers?

Some racers use different arm ratios to fine tune the engine. Usually the intake will be stock or higher ratio, and the exhaust stock of less ratio?

There is less stress on the rocker arm studs with less ratio. More with higher ratio. I've seen the studs snap with higher ratios. I stay stock.

No damage on the valve stems and retainers.

"Suggestion is appreciated
Anders"