Motordyne Engineering is the company, Hydrazine (Tony) is the guy and I don't think they have a website. He is a G35 owner and I believe there is a group buy right now on g35driver.com, you could also try PMing him on 350Zmotoring, do some searches over there for the couple of dyno runs etc. I am going to a dyno day but have a few other mods so I wont have a definitive this is how much difference it makes type of thing. If the GB is still on I believe the price was 150 (normally 200) for the kit 1/4 inch kit that fits the Z (without the bar you can go to a 3/4 kit). I paid full price but he refunded me the difference when the GB came up. He is a stand up guy in my book.
Chris