(First posted on MX5 nutz forum in May 2016)

I will only need it if/when I get as far as running injectors directly from the DET3 but I thought I’d see what I could do about providing a proper variable TPS for the DET3 while keeping the OEM 3 state TPS for the OEM ECU.

Had a look at the OEM TPS on the pre charger TB first then had another rummage through my various car spares and found a variable TPS off of a Rover K-series TB.  Think it was from a 56mm TB I fitted to my Mini.

The Rover TPS has the same D shape hole which was a good start and can be wired to go low or high and it just squeezes between the OEM TPS and the rocker cover.

 

Now on to trying to piggy back the Rover TPS on the Mazda one.

 

Insides pulled out

 

I machined an extended collar to replace the internals of the Mazda TPS and provide a shaft for the Rover TPS to fit on.

 

A quick bracket to hold the Rover TPS and allow some adjustment.

 

Parts ready to try on the car.

 

Finished and wired in to the DET3.  Not too pretty but it works.

 

MAF to MAP conversion and MAF delete next.