I have trusted Evan Steel Performance with my life as they built and maintained my race bikes for me from 2015-18. They are legit with a history of fastest privateer AMA/MA bikes. If I’m anywhere within driving distance of them in the future I’ll be using them again.
Kws has done my 675 heads in the past and were great. that being said, after working with Vance and Hines lately and seeing just how many heads and who’s heads they do (you would shit yourself if you knew just which teams sent their heads to V&H including factory efforts) they are definitely on another level altogether.
VHR has done the heads for all four Japanese Factory Superbike teams here in U.S. Three of the four at the same time!
Oh yes I’m well aware. It’s funny because people think “they’re Harley guys” but they know their shit. We needed a little “extra” from our husky last year and Byron personally did the last one. We found 2hp with head alone and that’s HUGE on the 450’s. In fact I would credit them largely to us winning our championship because it turned our program around in the hp department and even better was we never had an engine failure. They really do know their shit. have you been to the Indy facility? Omg I could have lived in there. Just spent hours asking questions and hanging out.
Graves/YMUS visited in 2015. Most of the juicy stuff was covered up (because it belonged to our competitors) but still an impressive place.
Call KWS. Godin is good and can help you decide if it's worth messing with it or not. Or get in touch with Aussie Dave and see who he uses - although I'd wait til next week.
I did check, that head is CNC ported by Kawasaki. Which means, it will be tough and costly to make it flow any better. Any good shop should be able to check and refresh it though. But, if you’re looking for everything you can get out of that head. I’d check with shops that do heads for drag bikes. Carpenter Racing and APE racing are both well respected in that area.