When you're considering a turbo option on your RX-5, there's a couple of options available for you straight off the bat. In this article, we discuss the pro's and con's of either solution, and if you even need to turbo at all?
Currently, at the time of writing, there are 2 options for the ECU to power your Mazda MX-5 based Indy. Both solutions allow you to upgrade to the turbo at a later date should you wish to do so.
Option 1 - The Standard MX-5 ECU.
When running naturally aspirated or NA, the stock ECU from Mazda claim 138bhp as their ""pub number"". It's half reasonable, but won't set the world alight. Yes, for a road car to toodling around the lanes on a sunday to and from the pub it's absolutely fine. It's been running for the past 20 years and it very likely to last another 20 years. It's a reliable tried and tested solution.
If you decide this is just simply isn't enough for you and you want some more power, then you can upgrade the stock ECU using a ME221 ECU which fits inside the stock ECU casing. It's simply a task of unscrewing the stock ECU case, remove the daughter board from Mazda, and replace with the Motorsport Electronics ME221 board. It uses the same wiring plugs, so there is no need for any upgrades, all you have to do is run a vaccum line from the inlet manifold to the ECU so the ECU can read how much pressure is building. And that's it ! a very simple upgrade.
Option 2 - The OMEX ECU
This solution is designed to make the wiring installation in the first place very simple. The OMEX ECU when running the car naturally aspirated claims a ""pub number"" of 158bhp, that's a 20bhp increase over the stock ECU and a redline of 7200rpm, which again is slightly more than the stock ECU. Connecting this ECU into the vehicle is simply a case of plugging several leads into the engine block (for sensors) fitting a new trigger wheel and plugging the OMEX umbilical chord into the bespoke chassis wiring harness - it's as easy as that.
The benefit with this solution is that with this extra 20bhp, do you need the turbo immediately? This is above entry level options for the competition of the Indy, so you could argue not. However, if this is something you should desire, MK make this upgrade even easier that the Motorsport Electronics upgrade. A quick engine map update and a vaccum sender later, and you're all wired to go.
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