well in the gen 1 range ther are 2 differnet n/a heads
one with yamaha stamped on it one without
basically the one stamped yayamha will have slightly cleaner ports and a diffrent casting methoud makiing tha yamaha head heaver
i have both head and you can have them both free + postage if ya want
they just need guide seals
the gte use the same casting methos at the yamaha ge head
but have a sholder in the port just where the injector is
there are a couple of different ge gen 1 models
the one with the yamaha head is the one you want
this comes with raised compression and slightly more agressive cams
these are apprently 159 hp stock
the rest are 10-30 hp lower depending on the model
i also have a gen 1 gte block if you want that as well
that comes with the water to oil cooler on the front
and the oil squirters
i also have the domed pistons from the yammy ge
they come with flatops on the non yammy head
at the end of the day i dont really know what you aiming for hp wise
so its hard to say
if you want high revs or massive cams your really gunna need to do the buicket over shim coversion
but i guess most of this comes withou saying
this is my observations on the gen 1 and comes from the 30-40 ive pulled to bits and hiffed or fixed
i have a shitpile of bits laying round doing nothing so feel free to have them my partner would love you
v
