Well here it is, your ULTIMATE guide to the KMiata BMW Transmission swap, for the DIY mechanic. I’m hoping this video teaches you new skills and motivates you to keep wrenching, no matter what kind of car you own!
I can’t wait to finally be able to bring the Miata back over 400WHP and see what kind of cars this beast can reel in! Should also be quite exciting to see how much I can really turn it up in the canyons, as I remember for the brief moments I got to experience the power, it’s a pretty scary car. Cheers to the beginning of the real fun.
Extra Supplies You May Need
Important Video Notes
Please keep in mind that this video is intended to be used in conjunction with the KMiata installation instructions. There are some things that may have been covered only briefly in the video which are outlined in detail in the PDF instructions. The following is a list of additional notes that should help you if you are installing this kit yourself. If you are having any trouble, feel free to reach out to me or to KMiata for assistance!
5:40 – In the bag of starter bolts, there is a single flat washer. Install the flat washer on the referenced “short bolt” before threading it in. This stops the bolt from sticking out of the other side of the adapter. (I failed to realize this and ended up grinding down the bolt which works as well, but isn’t necessary.)
7:06 – See the picture below for measurements to make a more centered cut than mine:
18:10 – See the picture below for a drawing of how to cut the bellhousing for more downpipe clearance:
18:39 – I highly recommend using these OEM mounts. There is not a lot of performance gain to be had with the stiffer transmission mounts, but you will have an immense increase in cabin vibration/NVH.
19:10 – It’s best to use an angle finder to be sure you’re at the correct angle. It’s a cheap tool (linked above).
20:09 – Make 100% sure you use a pilot bearing that has the correct inner and outer diameter for your setup!
39:15 – By “early chassis” I mean any Miata that has a cable driven speedometer, I think that’s only 90-93, but 94-95 may have had cable speedos as well. If you have a fat black cable coming out of your firewall right behind the speedometer, yours is cable driven.