Originally Posted by OKC370Z

I am posting this separately from the Stillen thread so it does not get lost in the hoopla. I want people to know that are some cars with the Stillen FI kit that have been working well with no real issues since day one and I have put about 3200 miles on this kit including one track day at Hallet Motor Speedway.

My car is a 2009 A7 and the FI kit has been installed since September 1st. The kit was installed with about 6,800 miles on it by Chris Cartwright with Failsafe Performance in Tulsa, OK.

The car was originally dyno’d prior to the FI install and produced 272 rwhp and 227 rwtq. Two weeks later after the install the car was dyno’d again on the same dyno under similar conditions and the car produced 389 rwhp and 290 rwtq. That’s a difference of 117 rwhp and 63 rwtq on 91 octane.

The results may not be what Stillen advertised but drivability is excellent and the increase in performance is very noticeable. First gear is almost useless and second gear has major traction issues. I love swinging out the rear in second gear as I am going through a turn in a very nice controllable fashion and then accelerating out of the turn.

The only noticeable issues are 1) when the motor is heat saturated and I stop the car and then get back in it, at times, it will not start without giving it a bit of throttle. At first I was like what the heck? But now that I am familiar with it I am prepared to give it a little throttle if it does not start right off as normal. It’s really not that big a deal now that I know what to expect and what to do. 2) When the temperatures dropped recently I started to experience some tip-in knock (detonation) when giving throttle under load. This happens mostly when at cruise and the trans is in a higher gear and the motor is in the lower rpm’s. To ensure I was experiencing knock I went to one of the few stations left in OKC that has 93 octane fuel, turns out that they had 101 octane for all the high end cars in the area (Porches, Lambos, Ferrari’s, etc.). I had half a tank of 91 octane in the car so I decided to fill up the 101 octane since the very next day I was participating in a track day. Once the fuel was mixed in, later that day I noticed a very noticeable increase in power across the board. I was surprised that increasing the octane would not only eliminate the tip-in knock but also increase the power as much as it did. I later found out talking to a friend of mine who was a Mercedes/Audi mechanic that Nissan’s VQ37 platform has a really nice knock sensing strategy that advances timing to maximize performance until knock is experienced and then adjusts accordingly. Wow! Is all I can say and now I try to fill up with the 93 octane (since the station is by my office) for the increased performance.

Does the Stillen kit produce as promised and without any issues? Well, not entirely but, performance is a bit subjective based on dyno’s, conditions, octane fuel, etc. and quite frankly I am very happy with the performance and the drivability of the car. The issues I am experiencing are minor and easily dealt with. So, overall I am very pleased with the Stillen FI kit and I am very, very pleased with my 370Z overall. My experience at the track day a week ago today was awesome. Unfortunately the weather sucked and we experience rain most of the day. However, the first two sessions of the day were dry (though chilly/cold track) and I was able to easily hang with a supercharged Corvette Z06 putting down 650 rwhp. We both kept our VDC systems activated since track conditions were not ideal. I actually had fun and enjoyed learning to drive with the VDC activated. With the track wet and cold without the VDC the rear would just come around and the car would spin out (I know, I tried it). With the VDC on it would intervene and keep the car from loosing the rear but would allow me to still swing out the rear and push the tires to their traction limits in the corners. I got to the point I was literally drifting the car through corners. Though the conditions were not ideal and I could not go as fast as I would have liked, it was a blast and I came to appreciate the VDC system and enjoyed experiencing a track day under those conditions.

That’s my story and I’m sticking to it.