G200 Auto to manual conversion

Thought i’d do a bit of write up on how i converted my detomaso from auto to manual. You will need the below parts to do it.

  1. Manual gearbox
  2. Clutch cable.
  3. Speedo cable.
  4. manual crossmember ( runs from radiator support to rear engine mount. )
  5. Flywheel and clutch assembly.
  6. Manual shifter.
  7. Manual pedal box
  8. Manual throttle body or modified auto one.
  9. Manual driveshafts
  10. Manual rear engine mount and bracket
  11. Passenger side engine mount.

Hopefully i’ve remembered all the parts but i will update the list if i think of anything else. Easiest thing to do is grab a complete donor car.

I started by removing the auto pedal which consists of just the larger brake pedal and replaced it with the manual pedal box as in the pic below.

You will need to drill out the hole for the extra mounting bolt of the clutch pedal in the firewall. Luckily daihatsu have already marked and centre punched the hole for you to make it easy. I used a stainless bolt with a nyloc nut and it’s as solid as the factory welded nut is. Next you will also need to drill out the two holes for the clutch cable mount and the hole for the cable to go through in the firewall. These are also centre punched from the factory.

Here’s a picture of the auto crossmember which has a different front mount setup.

Also in the above photo you can see to studs towards the rear of the floor opening for the shifter. These arn’t there in an auto chassis so you will need to drill out the conveniently centre punched and marked holes for them again and i used some more stainless bolts and nuts to create my own mounting studs. After all that’s done it’s a pretty straight forward swap, remove the auto box and chuck in the manual one.

The next problem i then ran into was the TPS being a different style on the auto to the manual. At first i tried to swap them over but the throttle shafts are also different and the manual TPS wouldn’t fit correctly. At the moment i have a auto throttle body modified with the manual throttle shaft with a modified TPS wiring loom to suit. It runs ok but i suggest swapping to a complete manual setup. I havn’t yet as i’m still chasing a detomaso one.

The wiring is the next hurdle and you will need to trick the car into thinking it’s in park or neutral to start. I’ve bridged the plug that connected to the neutral/park safety switch in the engine bay for the time being but am looking for a neater option in the future. The TPS wiring needs to be changed to a 3 wire setup from the 4 wire auto and a couple of pins moved to the correct spots in the ecu harness. The wire to the manual/auto terminal of the ecu also needs to be removed so the ecu then thinks it is a manual car. I’ve unplugged my auto ecu completely and it hasn’t caused any drama’s. You will also need to wire in the reverse light switch which is pretty easy to do with the help of the wiring diagrams in the manuals.

I’m not sure on wire colours or exact terminals but can have a look for anyone that gets stuck and will add some more pics shortly. Hope this helps someone :wink:

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Awesome write up mate, I’m sure this will come in handy for many people in the future!

Thanks