??W2 Econo valves??

long valves are need for econo heads that require long valves...standard valve length can be used with econo heads that use standard length valves...pretty simple...

the 5.29 and 5.28 sound about right for the long stem valves..

i got a set of each econo heads...long and standard valve lengths...might be able to measure the height of the pedestals...to help confirm which you have...