Mini Cooper S


In Fall 2011 I picked up a 2003 Mini Cooper S (R53) from my friend Andy.   He was the original owner and had a short commute, so despite being 8 years old, it only had 86k miles on it.

2003 Mini Cooper S - Post Detailing

This particular mini was used in a lot of early performance product development, and has had a lot of different aftermarket parts on it at various points in its life, as well as measurement points to do testing of all of those parts, including airbox temperature, pre- and post-intercooler air temps, additional map sensors, wideband O2 sensor, etc.  It’s probably had 5 different intakes, different intercoolers, 4 different exhausts, and a host of other parts.

The car started life as:

2003 Mini Cooper S

  • Premium Package:  Auto climate control, dual-pano sunroof, leather steering wheel with multifunction and cruise, on-board computer
  • Sport Package: Dynamic stability control (DSC), 17″ S-Lite wheels, foglights, Xenon headlights with washers
  • Cold Weather Package: Heated seats, heated mirros, heated washer nozzles
  • Interior:  Panther black leather, magnesium interior trim, park distance control, navigation system.

Current Modifications

  • Helix 19% supercharger pulley (also have a 15%)
  • Helix 380cc injectors
  • Helix short-shifter
  • Remus cat-back exhaust
  • RDR 19mm rear swaybar
  • Omori mechanical boost gauge
  • Summit racing digital oil pressure / water temp gauges
  • Whalen shift machine

Dyno Tests


144.1 whp @ 6250 rpm
129.8 lb-ft @ 4000 rpm

Modded:  15% pulley, Alta Intake, Magnaflow cat-back

173.1 whp @ 6750 rpm (+ 29.0 whp over stock)
158.5 lb-ft @ 4000 rpm (+ 28.7 lb-ft over stock)

Current:   To be determined, but estimated 183 whp

More Photos:

Mini Cooper S - Interior


Dual Sunroof




Repairs and Maintenance

Items I’ve replaced / added since I got the car in October 2011:

  • CravenSpeed strut-tower defenders
  • Coolant expansion tank
  • Thermostat / thermostat housing
  • Radiator hoses
  • O2 sensor
  • Serpentine belt tensioner

The mini isn’t complicated mechanically, but packaging-wise it’s hard to work on.  Things that should be simple aren’t, because of how tightly everything is packed.