you have 3 candidates: the old 462 (b ?), the 462-U, and the 462-UH
VERY preliminary testing indicates the -UH runs 3°C hotter than the -u
BUT
at the same pressure drop the die temp is effectively the same
rather interesting, and certainally of significance to WCing systems builders
(I hesitate to say designers)
the 'problem' that arises lies with building a system that is truly high flow, greater than 12lpm
we're talking BIG hoses, and NO fittings of the 90° type
g.l.amour
the old 462 is my preferred wb (I have 3 !), very easy to mod effectively
this will put you in the front row
the instructions are
here