Can four heater valves fit on a six?? I know that the six valves have the "hole" and I believe that the angle might be slightly different, but are the connection diameters the same and do the actuating levers match up??

Got my HE's leak tested and looking pretty good and want to re-install them, but thinking of shelving my really good condition six valves if the four ones will work. Thanks

In my book, they're the same.

I think the hole in the hat is due to the 911 fan moving more air at a higher pressure. The hole alleviates the possibility of the valve spreader spring being overridden. I have taken the hat off a broken /6 and placed it on a good /4 unit.

Thanks Slits, now to find a reasonable $$ set of four valves

I should be able to dig up a good pair for you. What do you think is a fair price?
Bruce