Adaptor Plates....Attempt No. 1

The monumental problem with the MX6 is that for some reason, Mazda decided their sports coupe would be front wheel drive. This also means that there never was a rear wheel drive gearbox designed to fit it. Nor does it particularly share any design with RWD applications elsewhere. Bit of a problem as I definitely don't want a FWD kit car...

However, nothing is impossible in my garage! Well....that is a lie. There is a lot that is impossible, so off to the garage to design some adapter plates!


My first attempt was to measure and measure and measure then mock something up in CAD, print off and see how accurate it was. If it was good, excellent, waterjet the aluminium, add some machining and jobs a goodun! Well that was the plan. After a few attempts of measuring and printing a paper template, I felt confident enough to try a 3D mock up. Cheap piece of MDF sourced (cheaper to buy than aluminium and easier to cut a prototype with) and my final paper template and off we went. So far so good! I wasn't exactly using precise measurements or tolerances however it came out ok....for the one side. Obviously tapping into wood and hoping to hang a gearbox off the other side wasn't an ideal scenario. However both sets of holes lined up to their respective designated positions. That's good enough for me to take the plunge for the real deal.

My first attempt for the throttle body adapter plates was not so successful. Aluminium is easy to cut and machine he says. Jigsaw with a metal cutting blade plus some time with the drill and filing combination should be a dream. Bit more labour intensive but saving money with my own man hours....right?






I mean, the general profile cut for the gearbox adapter worked out ok, even decided to do ALL the holes myself, why bother getting the waterjet to at least provide a pilot hole? Pleb. Anyway, using Mk1 prototype "woody" as a template I set about marking up the holes and drilling to the correct sizes. I had also found that Forstner drill bits for wood also worked well on Aluminium to provide a counter sunk hole without buying all the expensive machining equipment to do it properly, yay for cost saving. Just ignore all the mess it creates from drilling 11 holes, tapping 5, counter-boring 4 and complete clearance holes on 2. I definitely should not have done it inside.....

Ta daaa! A full set of adapter plates. Gearbox adapter, throttle body adapter and flywheel spacer. The flywheel spacer ensures the clutch mating is still the same with the gearbox as the adapter plate moves it away. So spacer designed and drawings to Red7 Engineering to turn up on the lathe and happy days!


I guess all that's left is to put them on the engine and cross my fingers they all work!





















So the plates fit to the engine. Gearbox adapter no problem, just need to calculate, design and manufacture a starter motor mount, due to fit in the triangle space in the bottom left. Throttle adapters required a minor touch up to fit properly but no issues there, angle grinder out and marked off chunk chopped out. Angle grinder fixes everything....mostly.















































All paws on deck! Once again I appear to be ignoring the use of my garage. Good reason too being visiting my parents and then being left to dogsit for a day. No problem, I have small things I can do....











......just don't let them come back and find you making a mess!




Whoops.







I ended up finishing them off back home in the end. Some paint on the adapter and modified linkages to accommodate the increased spacing from the T595 to the KL intake. Vauxhall injector rail with the bigger injectors was chopped in half and used as well (surprisingly the spacing fits well!). These are now ready. It feels like a little victory as I have missed a lot of things that have gone wrong or held me back. However I am fully aware that just because they are assembled here, does not mean they will work on the car....time will tell. It was a nice job to do in the warm of the house during the week nights, now to find a spare weekend for the test fitting....