I was also wondering how you were going to get the correct (around 0.5 thou ish?) tighter bore clearance using non-nikasil specific pistons? The Asso pistons were graded A and B I seem to recall. I have pondered MAP as they do a number of options, not sure if Gilardoni compatible is one of them?
What has always put me off personally, is spending a bunch of dosh and losing what is currently such a sweet, powerful motor, even if it is only running 7.something:1? The higher comp pistons will possibly be heavier(see below though) and the flame front compromised. With the cool running thanks to the alloy heat dispersion AND the tight bore clearance, I have never experienced detonation (and, yes, the low comp helps in that respect), even with the undoubted lack of squish.
I conversed with Jaye Strait of Britech in Maryland about 5 years ago and he has run a Gilardoni kit in one of his street bikes for 50,000 miles. Here was his response back then on my request for Gilardoni type pistons:-
"I'm familiar with the Nickasil kit I've got 49000 miles on one I fitted from (Triumph LF Harris) in 1988 to my T140ES. It works great. I can supply a set of Coated Forged pistons with Nickasil compatible rings to fit that cylinder @ 2.991" or whatever size you need".
in a further mail
"Pistons forged 9-1 or 10-1 std $429.90
Coating both $99
Gapless $79
Pistons are lighter.
520 sprockets $188.00
We have a Triumph 750 long rod w/ 6 full seasons of racing undefeated in Open GP
BSA A 50 with 61,000 miles.
T140D with 43,000"
Jaye has a good, if somewhat divisive reputation, no idea if he still does this or anything else? I also seem to have E&V engineering down as a possible source but never conversed.
Also, DanTriumph, J H motorcycles in Watford used to have new UNC studs for these kits. (my UNF threads are fine also though)