Supercharged 2010 Infiniti G37 Convertible

GTM Stage I SC
Upgrev Engine Mangement
Hotchkis Sway Bars

In the past I had looked at 240sx convertibles but she wanted to get a new car instead of dealing with something old and problematic. When I initially started looking, the Nissan 370z roadster came to mind. With two kids and a need for a back seat the roadster was shuffled to the back of the deck and we looked at a BMW hard top. Driving the BMW it felt old, it had wind noise galore and it did not feel very refined. I test drove a Volvo next and I’m not going to bother detailing that bad experience. I then pushed our budget a little and looked at the G37 convertible.

The first-year models were still out but at that time of the year the new 2010 models were starting to hit dealerships. We test drove both a coupe and a convertible throughout the process and noticed the ‘vert felt a little heavier than its hard-topped brother. In passing I joked to the wife that I should just supercharge the G ‘vert as a joke (assuming she would say no), but again the wife was full of surprises and simply said “sure”. Yow, did she just give me permission to throw boost on a brand new car? Thus, with added enthusiasm I looked at the model differences and decided that a 2010 would suit me better. Searching the internet I found the cheapest 2010 G37 convertible with the options I wanted, at a price that was well below invoice. I printed the information and went to Fields Infiniti of Lake County in northern Chicago. I expected haggling and excuses from the dealership as that’s what I’ve been used to with other brands. Instead, the Sales Manager took the sheet, did a lookup and found there were none similarly equipped in the whole USA and it would have to be special ordered. Expecting to pay a premium I was flabbergasted when he agreed to matching the price I found, $5k below invoice, and agreeing with a handshake. In August of 2010 I took ownership. Infiniti has won a long time customer.

While the car was being built and shipped I was busy researching different Forced Induction routes which were available. I saw a few vhr37 cars with turbos, but twin-turbo was a route I decided not to follow for various reasons – but one reason in particular: All the people I know with turbo systems on their cars constantly have to work on them. I’m sure some will disagree with that statement but it’s what I’ve seen and experienced. With that in mind I ran across a couple of new supercharger options via Stillen or GTM. These kits had just made their debut earlier in the year and not too many people had them at the time. After careful consideration, I finally selected GTM and received special pricing for being one of the first G37 owners installing their kit. What was truly unique is I’d be the first supercharged G37 convertible EVER!

After what seemed to me an eternity the car finally arrived and I took delivery. I proceeded to put at least 500 miles on the car before considering the supercharger installation. Being a “Do It Yourself” kinda guy and having a DIY supercharger kit I enlisted the help of a good friend Scott (NICO member maxhopper) who was willing to help. In October 2010 it was time to for the installation. I had all the parts, I had Scott’s help and I had a weekend available. After two days the initial installation was completed. A special thanks goes out to my wife for that weekend as it was our 5th year wedding anniversary. She sat back, took care of the kids and let me spend the whole weekend working on the car. I could not have done any of this without her!

Being a “first” in anything means there are some challenges and the ECU was the first one we ran into as Uprev, the ECU management solution we chose, had not cracked the ECU for this vehicle yet. It took a week for them to crack it and get it back to Sam at GTM. Sam created a canned tune for the vehicle and sent it to me. It was a tough week for me as I could not run the car until the ECU code was flashed in. Once completed, I was finally able to take the car for its first ride and all I have to say is I had the biggest grin a man could ever have. This car is just that damn fast. Over the next few weeks I did a number of canned tunes with the help of Sam at GTM. We finally got a tune we both liked and I able to hit a dyno. Base numbers for this care were 280hp/240tq, the final numbers after installing the GTM supercharger are 429hp/341tq. Other than the supercharger and ECU tune the cars driveline itself is still completely stock, including the clutch.

It’s been over a year since I’ve had the supercharger installed. Thus far I’ve had a single oil leak, which Sam at GTM addressed with new fitting. I have also had Project X here in town do a check on it as well just to make sure everything was running properly and the car is doing fantastic. I’m keeping the stock rims for now because I really like them. Other mods that are to come are spacers and maybe a spring drop. There are not that many available modifications for the Convertible today as there are not a large number on the road and the rear suspension is completely different than the coupe. I will not be getting a louder exhaust most likely as the car is already loud enough with the top down and the supercharger.

From a handling and drivability perspective I have stiffened up the suspension a tad by installing Hotchkis front and rear sway bars. Otherwise it’s stock and it does a great job. I’ve gone through a Chicago winter in all the snow with it and had no problems running on Pzero Sottozero tires. The car does break loose of course but I’ve learned to feather the throttle when needed. I’ve even auto crossed the car at the Carlisle, PA NICOfest event which was my first time autocrossing and I must say the last run had a very competitive time when all was said and done. During the event I had the top up but I have since found out the car is SCCA approved with top down due to the factory roll bars built into the rear. Looks like I may be doing some future racing with the top down. The car handles turns in general very well and I’ve drifted the car and no problems as there is minimal body roll with the new sway bars. It’s definitely a sleeper and will not disappoint anyone who is in it. I’ve let quite a number of people test drive it and they just come back with smiles on their faces.

Two thumbs up!

A detailed article of Dave’s GTM SC install is located here: Infiniti G37 Convertible Supercharger Installation