There are autocross builds and then there builds that focus on a no holds barred approach to prepping a car for class. The E46 M3 was one of the most raved about modern BMW’s ever made. Critics praised from the mountain tops about it’s rev-happy 3.2L inline six boasting 333 crank hp out of the box. They cherished and fell in love with it’s ability to take corners from the gate and BMW M Division set itself up again as being one of the best all around sports cars money could buy. As the owner of a pristine E36 prior to this car, Kai Jones knows a thing or two about working on this Bavarian icon as well. His foray into STU began not too long ago and, in what is a relatively short period of time, has transformed this slicktop E46 M3 into a uniquely distinctive STU build with some panache. It excites me to learn the details of this build and share it with you. As you read this I’m sure you’ll also get to know Kai and how meticulous he is as a person in ensuring that things are done properly. 

aj: What type of car do you have (mod list later on in the questionnaire)?

2002 BMW M3 – 6spd – Slicktop

aj: A lot of people give their cars nicknames/actual names. Do you have one for the E46 M3?

I have called the car a lot of names, most of them not nice when I try to give it nice shiny things and she makes it hard on me.  

aj: How much power is the car making to the wheels?

Good question.   Hopefully I will have it back on the dyno soon to see if the new exhaust made a difference (fingers crossed).   Last time it was on the dyno it was consistently at 306whp & 239/wtq.  It made one glory pull at 315/249 but we could never duplicate it again.  These are all done in Denver also, so roughly 5300ft above sea level.

aj: Mod List! Let’s have it!

Here goes nothing…. I know I will forget something

Engine & Drivetrain:  Stock S54 Longblock + Stock Getrag G420 6Spd +Stock LSD

  • Epic Motorsports Custom Tune
  • Eventuri Intake + MAF Tube
  • Mishimoto Intake Elbow
  • Epic Motorsports Headers with custom merge and 3.5” catalytic converter
  • Bimmerworld 3.5” race exhaust
  • Mishimoto Oil Cooler
  • Radium Engineering Air Oil Separator
  • Rogue Engineering Octane Shifter
  • ECS Stainless Brake Lines
  • ECS 2pc CSL size Brake Rotors
  • Sparta Evolution SSP 3.0 Brake Pacs
  • Vorshlag Polyurethane Competition Motor and Trans Mounts

Suspension & Chassis:

  • Motion Control Suspension 2 way w/ reservoir shocks
  • Ground Control Race Camber plates
  • Ground Control rear weighted jack spring mounts
  • SPC Lower rear control arms
  • Ground Control Race large front bar
  • Ground Control small rear bar
  • AKG Polyurethane Bushings
    • Diff cover
    • Diff carrier
    • Rear Subframe
    • Front lower control arms
    • Rear upper inner control arm
    • Rear trailing arm bushings

Body/Weight Reduction

  • RaceTech 4009w seats – Driver and Passenger
    • Bimmerworld billet floor mounts
    • RaceTech Side Mount plates
  • Schroth Quick Fit Pro Harnesses
  • OMP Targa 330mm steering wheel + adapter
  • Shorai Lithium Ion Battery

Wheels & Tires

  • Bimmerworld TE:AL Forged wheels – 18×10.5 + 27
  • 285/30/18 Bridgestone RE71R

Data System

  • Autosport Labs RaceCapture Pro MKIII box
  • Samsung Galaxy Tab S2 + SoloStorm

aj: The cars goal seems to be for street touring and we’ve seen Jeff Stuart have great success in his 350z in STU. With the influx of cars in STU such as the 987.2 Cayman S and even the Boxster and the C5 Vette, what are your thoughts on the chassis capabilities in this class?

That’s an interesting question, and one a lot of us local STU guys talk about a lot.  In fact, we have even gone to the extent to create a spreadsheet that details data from real cars that we know to show power to weight, use of tires, weight distribution and power band for the gearing.  It is really interesting to see on paper what should be the most dominant cars in STU.   I do think that the e46 is honestly a quiet underdog but given the right prep and driver, I honestly think it is capable of winning an STU title.  On paper, the most dangerous car if really prepped for STU is actually the Fiat 124 according to our calculations.

aj: What was the biggest “surprise” or obstacle you faced when you worked on the car (as in what was maybe supposed to have been an easy task but ended up being a pretty huge undertaking)?

I think this has to easily go to the exhaust.  Every other car the exhaust is such an easy bolt on and done, the e46 has been 0% that.  I am on the 2nd version now, and to say it has been a challenge is an understatement.    To get the maximum performance while staying within the confines of the STU ruleset has been a massive challenge of customization of nearly every part.  Hopefully, it is done now, for a while.   Until I have to make it out of Ti so that I can save another 10lbs, because you know, racecar.

aj: Do you data log at all? What kind of data-logging system do you use? How easy was it to integrate the software into the OBDII system of the e46?

I do and I wish I would have invested in it and started using it so much sooner. It has paid big dividends in our driving skill improvement in a very short time!  Our user interface and logging we use a Samsung Galaxy TabS2 that’s hard mounted to the dash running SoloStorm.   Our data system that feeds SoloStorm is an Autosport Labs Race Capture Pro MKIII box that is wired directly to the OEM CAN system.  We also have both OEM brake pressure sensors wired to the box currently and plan to add in a wideband and oil pressure as well.    The Race Capture box also has its own 5 axis gyro for accurate G load data and its own external GPS that we can run consistently at 25hz refresh so our driving line data is super accurate.  I definitely geek out over data from the car and runs.

aj: Let’s talk suspension. What do you think is one thing the car could do better (i.e. sweepers, hairpins, transients)?

Honestly,  nothing.  I can honestly say I am super happy with the way the car feels right now.  It transitions well, can sustain a high G load in sweepers, and gets in and out of hairpins as well as a RWD car can be expected too I think.  Obviously, there is always a little give and take between those three so the car is never perfect on all of them at the same time but I think we have got it dialed in pretty close to a perfect balance right now. We do make little shock changes based on the surface and course design to really make sure the car excels at whatever the dominant features are of any course but those changes are very minimal.

aj: What would you say the car’s primary strength is?

Personally, I think the car can slalom better than any other car in the STU grid.  The car is so well corner balanced with so much mechanical grip that when it needs to, it can just dance through slaloms at speeds that seem to be a couple mph faster than most others can do it.

aj: BMW has had many liveries throughout the years – what made you decide to go with the Art Car theme?

Jeff Koons art car just stood out to me as an incredibly instantly iconic design like the traditional liveries of Gulf, Jagermeister, Martini, or Marlboro.  Truthfully I am normally a clean, simple and subtle kind of person so this livery was way out of my comfort zone.   I was doing some contract work at Impacted Wraps and Graphics in Denver and Cam, one of the guys there, wanted to take on the challenge of doing this livery onto an e46 so I just said “let’s do it!” and he crushed it out of the park.  So here we are.

aj: Are there any sponsors you would like to acknowledge for their assistance in getting your car to the way that it is?

Absolutely!  There is a lot of people and companies that have helped me with this car to all of them I am very thankful and eternally grateful.  There are a few I would like to call out by name though:

  1. Brad at Chicane Motorsport.  Brad has helped me with this car almost from day one.  He got the subframe squared away so I never have to worry and has always guided me right with what parts are best for the car when I need advice.  Brad has also sourced almost every single aftermarket part on the car for me and gotten me the best prices and fast turn times.  Chicane Motorsport is truly a great race shop for racers and run by a racer.  Thank you, Brad, for always helping me with this car and helping me at any and all hours of your very busy day!
  2. Lex, Wyatt, and the team at Motion Control Suspension.  This is the 2nd car over the last 4 years these guys have helped me with and I continue to be more impressed by them every time I have another interaction.  Thank you guys for always helping me out with knowledge, advice, and support for your amazing dampers.  This car wouldn’t be nearly as good as it is without your team and their hard work.
  3. John and his team at Sparta Evolution.  Special thanks to John for always making sure my brakes are as good as they can be.  They have developed and continue to develop better brake systems and pads for racing enthusiasts so you can be confident about getting hard on the stop pedal at the end of a long straight.  I can never say enough good things about the SSP 3.0 pads, they truly are magic.
  4. I can’t forget my good buddy Alex McCulloch and Glen Shelly Auto Brokers.  To say this build would have never been possible without him is the 100% hard truth.  For fun, here is the article he wrote to capture the story of how we got the car, it was a crazy adventure:

Also big thanks to Eventuri, Epic Motorsports, RaceTech USA and OMP Racing for making awesome products and supporting them!

aj: As most of raced cars undergo continuous changes, what are the next plans for the car?

This offseason I think will be mainly about maintenance and preventative maintenance since we are already almost all the way maxed out for STU. Currently, the list includes rod bearings, VANOS rebuild, valve adjustment, cooling system overhaul and upgrade, check and refine tune, and if time and budget allow I would really like to put an OS Giken diff in the car.