I've got a 292 in a 55 t-bird. Engine has less than 50k miles. I pulled the valve covers to set lash and found some of the rocker arms are not centered on the valve stems. They are off as much as 1/8" to 3/16". The ones that are off are too close to the mounting pedalstal. Is this normal? The engine is clean inside. There doesnt apear to be any excessive wear. It runs good. Are their left and right angled rockers and mine were put in wrong? Should I replace rocker arms? Should I install spacer washers between rocker arms and pedalstals? Should I set the lash and close it up?  Any help would be appreciated.

[quote][b]Tedster (1/14/2019)Is it a given that a compressed spring loses tension over time? I'm not persuaded this is necessarily the case, and even less that it would matter with a P&G valve gapper...

Spring ‘creep’ (the relaxation of tension from being compressed over time) is a measurable scientific fact. The degree of relaxation and it’s relevance to function is dependent on many factors (material, force, temperature, use, etc.). The only way to be sure of the simplest issue (time only), would be to find a NOS (new-in-the-box/unopened) original/unassembled unit (or replacement part), and measure it’s tension for comparison to another NOS unit/spring that was merely assembled, but never used. It IS possible that MY P&G tool was consistently used daily in a busy shop for many years to set valve lash while an engine was running, and then left attached to a hot motor until the next job. THAT would certainly wear out the spring much faster. I can only assume (from the P&G instruction manual and 50s era car magazine articles) that the original device must have worked better when new than mine does now (?).


6 VOLTS/POS. GRD. NW INDIANA

Well... I think we're getting off into the weeds just a bit. The P&G gapper tool is simply a very accurate method of setting valve lash particularly on well used rockers, I've measured the lash both at a slow idle and when static and the lash indicated on the dial is identical.

I think the main benefit of this tool is not just an increased precision but also that the lash has a consistency across all cylinders, that contributes to a very smooth idle. Most people though, aren't going to bother or care.