I've been quietly working on Hyper in bits of spare time here and there. Lots of cool stuff in the works. Debated about how much to share because inevitably once I start showing stuff others start to copy it. But I'll risk it, want to bring you guys along on the journey.
Let's start off with explaining that this update is specifically and only happening because of where this car competes. Global Time Attack has evolved to now require a spec tire model in each class. The tire for Limited class is the A052 and that is not available in any wide sizes for 15" wheels. Fitting larger wheels on a Miata properly is not an easy feat, and this likely means we'll see less NAs/NBs competing in GTA events. But unlike others who run their cars for fun in many different series, the HyperMiata is a single-focus car that is all about trying to earn that top spot at the largest time attack event, and that is GTA. So I'm doubling down and committing a lot of time and money to converting this car to run some big rubber.
Left: our old 15x10 with 245/40/15 Rival S 1.5. Right: 18x11 with 295/30/18 Yokohama A052.
Custom 5x114 front and rear hubs get the wheels bolted to the car:
Brakes have to be changed to work with the new hubs. I've got half the parts or so for that already with drawings done and parts in the works for the rest.
Now let me be clear: our recommendation has always been and will continue to be that you NEVER want to put large 17" or 18" wheels on an NA/NB. Don't do it! This car's situation is so specific, and even then I agonized over whether to pull the trigger on this for a while. The new tire offers a larger contact patch and stickier compound than the smaller Rivals we were running, so the potential is there for more speed, but there are some massive challenges caused by the larger wheels that all have to be overcome otherwise it's just a big step backwards.
Custom hubs and brakes are the easy part. The real mountain of work is in providing room for the massive wheel's range of motion.
Current state of things is I've been cutting... and cutting... and cutting. Basically cut out as much car as needed until full range of motion is there, and then see how much car is left and rebuild around that. This is cutting into some rather critical parts of the tub so as I'm cutting I'm planning how I'm going to rebuild these areas to keep load transfer through the areas that need it. Otherwise the car would end up a floppy mess.
This is where the front is at, with still some more cutting to go. Those holes go into the interior of the car. If the fiberglass blanket wasn't in the footwell and someone was sitting in there, you'd see their feet through the hole.
The rear is nearly done in terms of cutting and I've started some of the new pieces.
Yep, that's the new rear wheel tub protruding through the rear parcel shelf into the interior of the car:
When the sheet metal is done, the bodywork will be a whole separate project because new fenders will be needed. Feels like I've been at it for a while already but there's a mountain of hours ahead. Right now I'm just putting my head down and keeping on plugging away at it day by day. We'll get there.