Are these rotators?

Like I mentioned before, they are in a 2x6 stud wall. I drilled 5/8 holes crossways through the studs and have some 1/2" steel rod slid in front of them. Now as for those mid '20s vintage overhead valve briggs and strattons, I think they are lag bolted down.
 
I think this is right - Ford deleted the valve inserts and just ran the valves straight in the block. To compensate for this downgrade, they introduced rotators on the valves. The slow rotation of the valves helps with seat life, offsetting the effect of the deletion of the inserted seats.

i could have just made that up but I think it is right.

Mart.
 
Rotators were kind of a new thing at the time so I think that is one reason. Better fuel availability was also part of that decision in 1951.
 
So do I get bonus points for using rotators AND hard seats? Actually, since I just reset the valves (for the third time), I'm not really too keen on the large lash settings called for with the rotator assemblies. Van Pelt site specs call for .013-.015 for intakes and .017-.019 exhaust. Since I'm certainly no hot-rodder, and not a fan of the 'lopey idle', I love the smooth, near silent idle of the stock flathead V8. Will this engine be a little noisier than what I'm used to with the larger lash settings? Since it has hard seats, could I use the clearances for the earlier engines without harm, perhaps making it quieter? I do understand that the lopey idle is from a reground cam and the noise I'm referring to is lifter clatter, but nonetheless, I like em smooth and quiet at idle. I'm not in a position to buy new valve gear at this time. Thanks.
 
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Valve rotators in the flathead is of non-positive type...which means engine vibration randomly makes the valve rotate.
The extra clearance shouldn´t be needed for rotation.
My thinking is change in camspecs and added power/heat lead to new clearance specs.
Rotators work as good on hard seats as on castiron.
We have to keep in mind that ford didn´t make changes to improve performance only...they did it to make money...Muntz engineering
 
Sounds like I just may use the 59ab valve lash specs. I'm sure it has the earlier style cam in it as the crab distributor. I have the pan back on and after the valves are adjusted (for the 4th time), I'll continue to add components. I put a starter in it last night and primed the oil pump. The engine without heads, cranking on 12 volts runs the mechanical oil pressure gauge up to 60 lbs. Sounds promising. On the other front, I chased all the block threads with a headbolt with a slot from a cutoff wheel. All holes now look great. I have about 100 head bolts and I high graded my meager stud collection for the engine I built last winter for the woodie. With hobby funds deleted by the woodie project it looks like this is a head bolt engine. The cleaned up threads give me newfound confidence.
 
I was doing a search on valve lash with rotators and came across this from 2017. Looks like pretty much everything I'm doing now I just did seven years ago and forgot what I did. Kinda scary, but I got a lot of good info that I can now use again.
 
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