Why do the swap?

Most people would question why I’d want to get away from the cable-based throttle body on the miata. I don’t disagree that mechanical systems are generally simpler to work on and easier to debug. The drive by wire (DBW) solution can also be a safety concern as well if the system doesn’t have proper fail safes implemented.

The simplest way to summarize the pros of a DBW setup is, “more features with fewer things to control.”

• built-in idle control. no need for a separate idle control valve.
• built-in cruise control. no need for a separate cruise control motor to pull on the throttle with yet another cable.
• traction control by pulling throttle (albeit, pulling timing might be more responsive)
• throttle blipping (for pontential DCT swapping in the future :))

Finding the parts

I hit up the junkyard for some OEM parts. I chose to look at Toyota throttle bodys because I wanted a part that would be easily accessible in the future in case I needed to buy a replacement. The throttle I chose was from a 2003 Toyota Camry with the 2.4L 4 cylinder engine. I was able to test fit the throttle on a 1.6L miata that was also in the junkyard.

Cleanup

When I got home, I removed all the coolant/vacuum ports that I wouldn’t be needing. I sealed some of the holes with JB weld to prevent vacuum leaks or water getting into the housing.

Psssttt… here is a link to part 2