Hydraulic Lifters in 1/2 Dubs???

[Slohand42]

In reading through Bob Hoover's stuff I saw that he recommended hydraulic lifters for his VW Airplane engines.

"Based on dyno runs of factory-built VW engines running both solids and juicers,
the hydraulic lifters clocked an impressive increase in output right across the dial.
Even a hot adjustment, tweaking the solids to near-zero lash couldn't make up
the difference. The juicers simply do a better job."
And, Aircraft engines were among the first to adopt hydraulic cam followers. Some
form of hydraulic valve-lash compensation is standard on all modern engines,
even those running overhead cams."

I haven't seen much discussion about hydraulic lifters in this group.  Is anyone using them?  If so, why?  If not, why not?

Thanks,

[Kamcoman77]

MOFOCO makes a hydraulic lifter kit for VW's that requires no case machining. The cost is between $400 & $500 depending on stock cam or slightly hotter. Spending an extra $400 for an unknown increase in horsepower is not on my bucket list. I'll stick with tried & true since Hoover does not state how much of an increase ("impressive increase") might be available. Perhaps someone who has hydraulics in their 1/2 VW will chime in, but I've never heard of anybody doing this.

[Slohand42]

Thanks Kamcoman,

That’s what I wanted to know.

I found a drop in set for $250 which is still high.

I’m not looking for more power as much as not dealing with the constant readjust issues that some talk about.

[Kamcoman77]

I think a little maintenance every 25 hours gives the pilot a chance to check a lot of things over more carefully than a pre-flight. Checking things like wiring connections, oil cooler fittings, nuts & bolts, are just some of the things that should be checked at oil change & valve adjustment time. As a general rule, after the first couple of times adjusting the valve clearance, it won't need it again unless something is wrong internally. That is a great warning sign to suggest a more thorough check of engine internals.

[Slohand42]

Once again thanks.  That sounds good.
I just heard back from Scott Casler who does not recommend hydraulics, so solids it is.