I have taken my modified LJ GTR with triple 45mm webers for these guys to dyno tune it a few times 1st when I had my engine built and then for maintenance adjustments as webers are awesome but need to be balanced correctly. They do really good work but a bit on the pricey side IMO.

I take my car here to get it serviced- being an R32 Skyline it needs to be looked after if I want to keep it in peak condition. They are pretty good. They give you a print out and tell you if its having any problems. The car always runs better after the tune and any problems can be dealt with before they get worse.