I completed a DIY Stillen SC installation on my 2009 sport/touring Z (auto trans) 3 years ago. I posted this shortly after completing the installation, adding today this post's penultimate paragraph as an updated evaluation after 6K miles of living with the beast.
There are several areas in Stillen's instructions that will trip up even ASE-certified first time installers. I prepared the attached instructions to help others around those areas. The photos that go with the instructions are in my 'wortmeister' album on this site. Most cases of dissatisfied owners are due to installer error. If the car ran well before installation, it'll run like a striped-fundament simian after--as mine does. I made a couple of doozies myself. Took me 6 hrs. to find and correct the mistakes (2 bad MAF wiring connections and a FUBARed manifold gasket (see 'wiring' and 'troubleshooting' in my instructions)-but it was worth it.
This is a great kit, and worth every penny. Fit and finish of parts are so good Nissan would be proud to claim it as an in-house production. The kit is complete to the point you probably won't have to leave your garage to complete the installation--as long as you have a fiber-optic scope to use while installing the right-side manifold bolts. Stillen somehow "overlooks" this requirement. With my instructions filling the gaps not covered in Stillen's, any average DIY mechanic can install the kit in less than 20 hours.
If you want an astonishing increase in torque/horsepower, while retaining the docile, refined character of the touring Z, this is the way to go. I don't have dyno results after the SC installation, but can relate objectively the following: 1. Even with the VDC on, I can't use more than 1/3-throttle for launch without getting wheelspin so severe it moves the back of the car sideways; 2. The performance increase isn't just my opinion: friends I've permitted to drive it before and after now uniformly exit the car after a test drive with an open mouth and the words, "Sacred fecal material! (I expurgate the words to avoid this forum's rules regarding profane and obscene language). One porscheophile friend states it's as fast as a mid-'80s 930 turbo--but a lot more manageable.
I don't race the car professionally, and am careful about when and where I make full throttle runs. I live in Phoenix Arizona, where 110 degree summer temps are the norm. The car has performed flawlessly during the 6K miles since I installed the Stillen, with no service other than oil and filter changes. Sorry, I wouldn't have a manual transmission. Not only does the 7AT make it a pleasure to own as a daily driver, but I pick up a car length at stoplight grand prixs every time "nearby" traffic has to shift their manual. If the Stillen costs anything in gas mileage, it's negligible, and easily worth the increased performance. I'm using the Stillen/Uprev tune supplied with the kit. While a custom tune might pick up a few horsepower, tuners largely ignore what happens at less than full throttle. As previously noted, my supercharged touring Z is the same docile, refined machine Nissan engineers designed it to be--until you nail the throttle.
As icing on the cake, it passes Arizona's stringent emission test, which is right behind California's in difficulty.
The attached instructions must be read in conjunction with those Stillen supplies with the SC kit. Unfortunately, Stillen no longer allows downloading the instructions unless you buy the kit. I've also attached the instructions in .pdf format, readable by anyone with Adobe Acrobat. This is a link to the pictures in my album on this forum that go with the instructions:
Nissan 370Z Forum - wortmeister's Album: Stillen Supercharger Installation pics
If you're serious about an installation and wish further info, ask for it, and I'll respond. Duane Isaacs,
etymeister@aol.com