ST Generator efficiency?

[veggie]

Does anyone know what the average efficiency is for the ST style generators when running in the "sweet spot". The ST-3 in particular.
As I understand it, the newer design brushless 3600 rpm heads used on today's "screamers" are about 92%.
I was wondering if the ST heads fall in the same efficiency range.

veggie

[veggie]

Anyone ?? 

[Henry W]

I don't know how efficient they are. Todays brushless are probably higher efficiency. But 92%, that seems pretty high.

[Tom Reed]

IIRC around 80%. My 6/1cs is rated for about 4.4kw and will put out about 3.6kw continuous.