Black MK1 1.8 Supercharger

We bought a black 1997 MX5 MK1 Classic in standard condition with the 1.8 litre engine. As a test we decided to take it on a track day with no modifications. We went to Snetterton and the performance was limited to say the least! On the long straight we only scraped 90 and it was like a boat in the corners.

Something had to be done, so we decided more power and improved handling was necessary. Here are the modifications we made:

Engine

  • BMW Mini M45 Supercharger (Initially standard pulley and no intercooler)
  • TR Lane mounting hardware
  • Megasquirt MS2 ECU
  • Inlet air temperature sensor (allows air flow meter removal)
  • Toyota Pencil Ignition coils
  • Wideband lambda sensor
  • Twin throttle bodies
  • K&N airfilter

Suspension

  • Flyin’ Miata up rated anti roll bars
  • Racing Beat adjustable anti roll bar links
  • Rokkor adjustable coil overs
  • Our custom four wheel alignment

Other Items

  • TR Lane roll bar
  • Team Dynamics Racing 15” wheels
  • 195/50/15 Toyo Proxes tyres
  • EBC Yellowstuff front pads

With this set up we were only achieving 4PSI of boost which made a very nice road car but on the track the performance was lacking, particularly at higher revs. We decided we needed to spin the supercharger faster so we added a Jon Speed 15% smaller pulley. A brief road test showed more performance but very high intake temperature and pre-ignition. To overcome this, an intercooler was neatly installed in front of the radiator.

The result was over 6.5PSI of boost and an engine that pulls smoothly and rapidly to the red line. On the track the car has proven to be fast, tractable and great fun.