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Converting Your MX5 from Auto to Manual

Converting Your MX5 from Auto to Manual

First off, let’s see why anyone would want to do this. It’s a matter of preference, but some automatics have been known to cause problems. Moreover, owning an MX-5 is mostly about sheer driving joy. It is a lightweight RWD car with just enough power to provide fun, but not enough to have you praying to god every time you press the pedal. It is about a mixture of relaxed topless cruising and precise steering enhanced by lightweight body and RWD packed with just enough power to put a smile on anyone’s face with the pedal down all the way. It is about driving joy and it is best with a conventional manual.

How do I get a manual MX-5?

Buy one! This is the best way possible. The people at Mazda know how to make a good car and if you have an option to buy an MX-5 with manual, this is the best way. However, when buying old used cars, there is one thing that is more important than any other – condition. If you find a mint MX-5 with an automatic gearbox – and you want a manual – conversion is possible and not as difficult as you might imagine, although not really a walk in the park either. You will need various different parts in good condition, a different or modified wiring harness, etc. Let’s see how this is done…

What Parts Do I Need?

Obviously, you will need a good condition manual gearbox, flywheel and bolts, clutch drive plate, spigot bearing, clutch pressure plate, release bearing, gear lever, gear-gaiter(boot), gear-lever insulator rubbers (top and bottom), clutch master cylinder and hydraulic lines, clutch slave cylinder, brake and clutch pedal assembly, power plant frame and prop-shaft. These things are a must, but there are others that are different as well. For example, the automatic uses a different radiator that is heavier than the one on the manual. You don’t have to change it, but it will reduce weight further if you do.

Removal of the Automatic Gearbox

You will probably not be able to do this alone. Not due to the technical stuff, that one is pretty straightforward and all you need to do is follow the manual, but some parts are pretty heavy. The manual transmission alone is not all that bulky, but the automatic one is impossible for an average person to handle alone, we recommend hiring professionals for a job of this capacity such as the team at MX5 City. Also, supports for the car should be very robust, for the same reason.


Half of the work will be dealing with the wiring. There are many things to take into consideration and many of them will completely depend on a particular case. For example, not all cars have the same accessories, so there might need to be a significant amount of work for simple things like the problem of a source car having electric windows and the other one not. Even if we neglect these accompanying issues, there are still significant differences between wiring systems of a manual and an automatic. The automatic has dedicated harnesses for the control unit, kickdown, cruise control off switch (if fitted), gear selector, throttle position sensor and six more harnesses for the transmission. So, yeah, there’s a lot to think about.

Additional tips

These have come up during the swap process and they are basically experience condensed, so pay attention.

  1. When you are on the inside and pulling the wiring and swapping over the pedal assemblies it is a lot easier to do it with the seats removed. This is a surplus piece of advice for anyone who has removed them at least once, but for those of you who haven’t – there are only four bolts per seat and the amount of space this will give you is immeasurable.
  2. When removing the dash to access internal wiring, make sure you disconnect the three cables that control heating and ventilation before you try to remove the dash to avoid damage. It is not a huge issue to fix even if you forget this, but this is most definitely not something you will welcome during such a major task that swapping the transmission on an MX5 is.
  3. Make sure you DO NOT simply swap the entire instrument cluster. Although this might prove easier from a technical point of view, it would mean that you would also replace the odometer and this might be considered tampering with it. The authorities and future owners might frown upon that, as you can imagine.
  4. Make sure you install the slave cylinder after the transmission has already been placed.
  5. You may need to recalibrate the speedometer.
  6. The best idea would be to have an entire car with a manual so that you can simply remove a part from the source car and install it on your own. This would make things a lot easier. Furthermore, you could also install the automatic you removed to the source car and sell it, thus greatly diminishing the costs of the entire endeavour, or you could save the source car for loads of spare parts.

Here at MX5 City we have carried out many conversions on both Mk1 and Mk2 models, so if you don't fancy the task yourself, we can do it all for you! We use a good condition used gearbox, new clutch components, new clutch slave cylinder, good used pedal assemblies, PPF, etc. The approximate cost (of converting a Mk1 NA model) is £1,350 including VAT, parts, oils and labour. For further information and to book your car in call us on 01977 233555 or email: