Full details in @///cloudarch's words:
I've been meaning to write a review of my E46 M3 Supercharger kit which has been the source of joy for over 2 years now. I figure this has been long over due and wanted to share what my experience has been. I hope this can serve as reference for E46 M3 owners exploring the FI route.
I first visited the Gintani shop in Van Nuys, CA in early summer of 2011. I had completed my first mod on this car (Eisenmann Race Muffler) and was instantly hooked. I was looking to source a cold air intake kit and had been calling a few shops in the valley to see if anyone had experience installing these on E46 M3.
The owner of one shop who works primarily with Porsche customers referred me to Gintani and suggested they would be able to help. I drove one day to Gintani's shop and discussed with them my interest in modifying my intake system in hopes of achieving an aggressive induction growl and possible gaining some extra horsepower. That's when I was introduced to FI and the Gintani kit which could yield massive amounts of power over my existing NA setup.
I took a few visits to their shop to discuss my options and also get familiar with their staff. I also researched other S/C vendors and their kits during this time but I was really intrigued by the fact that there were very friendly to me from the get-go and the fact that they were local was a huge advantage. I travel about 80% of my time so considering the expense i was looking at and the risk that big power introduces, I knew that having someone in my backyard that I can turn to should problems arise was going to be a benefit I would struggle to have with anyone else.
So I pulled the trigger on the Gintani Stage 1 Supercharger Kit in August 2011. My car had just over 78k miles then. The kit was installed shortly after including a custom tune with their in-house dynamometer (Dyno Dynamics) resulting in 386whp and 273 TQ. I have had a constant smile on my face driving my car with a lead foot ever since.
The following is a summary of notable updates since then:
1. October 2012, Upgraded to Stage 2 kit
Mods included Fabspeed headers, smaller pulley, larger fuel injectors and a retune
2. November 2012, participated in Airstrip Attack II
My wife and I had an awesome experience at this great event organized by the Shift S3ctor crew. I was probably one of the slowest cars there but glad to have had an opportunity to take the car up to high speeds in a friendly controlled environment. We managed to hit 140mph at the 1/2 mile mark on our best run (not bad for a 3753lbs convertible plus two passengers ). My car was at 95k miles around this time.
3. February 2013, Spark Plug maintenance
Performed this work myself at 100k miles. Installed the same spark plugs which came with the S/C kit (NGK DCPR9EIX Iridium IX)
4. March 2013, dyno day at Creations and Chrome in Santa Clarita, CA
2 dyno runs on a DynoJet with best run resulting in 474whp and 326TQ. Setup included Fabspeed header, OEM Section 1, OEM Section 2, Eisenmann Race muffler. You can see in the power curve a bump just past 6500 RPM that I attribute exhaust flow restrictions.
5. July 2013, Valve Adjustment and Exhaust modifications
Had the guys at Racewerks Engineering perform a valve adjustment with new gaskets. Also installed used OEM Euro section 1, new Supersprint Resonated Section 2 and Supersprint Race muffler. The car now had 106k miles.
6. January 2014, Shift S3ctor Dyno Shootout at European Auto Source
I got wind of this dyno day hosted at EAS on Saturday 1/19/14 and took advantage of the opportunity to get my car dynod. I hadnt had the opportunity to dyno the car since the exhaust modifications back in July. I was ecstatic at the results from 3 dyno runs. Consistent power curve as you can see from the chart below. The drop at high RPM range seen with previous exhaust setup is no longer observed. The Supersprint mods have clearly delivered on their promise. Car is now at 112k miles.
To conclude, I have to say that I am more than happy with this kit as it has delivered to every one of my expectations: reliability and consistency. After 2 1/2 years and over 30,000 miles of abuse, the kit is still running solid and putting down great power.
I will eventually be looking to hitting the 600whp mark with a custom engine build. I have my first child on the way so who knows how realistic this goal is but at least I have something to dream about.
Thanks for reading!