Wingman703

5 lug? I take it you are commiting to a 16" wheel for tire sizing choices then?

ThePass

iTrader: (3)

More bigger

ooja3k

iTrader: (1)

Right on! I'd love to see how much work (im suspecting a LOT) to get a bigger wheel and tire under there and whats its effect on center of gravity, roll center, etc ends up being with the car higher off the ground

ThePass

iTrader: (3)

It's going to be a long path with a LOT of work no doubt, but it was inevitable... the snowball continues to roll downhill

doward

18x10.5 +15 295/30/18 Nissan fitment should fit your flare situation off the shelf.

ooja3k

iTrader: (1)

Thats 2" taller, and 1 of those is straight up, not to mention inward towards the shock towers in front. If it's possible, there's no doubt I'll try and follow as GTA with the Yoko's has handicapped all our miatas unless we get to cutting a lot of metal out of the way

Lurch

Wonder how well an 11 would fit. Assume it would be faster on a 295.

ThePass

iTrader: (3)

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 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.

ooja3k

iTrader: (1)

wowwwwwww

griff

Did you hear that???? That was the sound of me pitching the hopes of ever running my turbo LFX in GTA right out the window. Can't wait to see your handy work Ryan and I have ZERO doubts that Hyper will be worth the investment!

Wingman703

With that much metal cut out, I'd find it hard to believe that the OEM shock mounts will remain unmolested without hampering the wheel at full compression. How are you working around GTA's Limited class rules that state "OEM front and rear shock towers must remain intact and attached to OEM tub as stock....The shock tower may be modified to install shock mounts reinforcement or spacers but the OEM structure must remain in place. They may be clearanced for engine swap fitment only." ? Or are you moving Hyper into Unlimited?

Twibs415

iTrader: (8)

The rules are pretty loose. I got word back that something like this falls under “fender clearance” verbiage. Keep up the good work Ryan!

ThePass

iTrader: (3)

I'm confident I'm operating within the ruleset.

sixshooter

iTrader: (12)

Have you ever had the feeling the organizers are trying everything they can to make you and others with Miatas go away?

emilio700

iTrader: (3)

The organizers are using a variation of 25 year old Japanese time attack rules. No specific Miata hate. The tire sponsor is not making any special tires to accommodate unique platforms, such as the Miata. The West Coast Yokohama Motorsports distributor is across the street from us. I was talking to her about the problems time attack Builders face with getting the right tire size. She asked what size I would want and agreed that it would take a special mold. Yokohama, as a policy, will not put a plug into an existing mold to make it wider the way Hoosier and BFG will. They insist on a separate new mold for each tire and she mentioned roughly how much those mold cost. So a 305/30/15 A052 for a handful of drivers would never happen.

The cultural legacy in time attack is unlimited horsepower. There has never been any discussion about building power to weight classes like you have in Club racing. This means there will never be any concessions to smaller cars, engines and tires. The unfortunate result of this is that the resultant cost to build a competitive car skyrockets. Which is why there are so few fully developed cars that show up for these events. You might have a dozen cars in the class but only one or two actually run all day and are well..fully developed. The rest are hastily cobbed together woefully underdeveloped, slow and desperately unreliable budget builds.

The magic of time attack is those scant few fully developed cars running at full song. Those are some brief moments of pure poetry in Motorsports.

Lurch

All of this kind of reminds me of the Mighty Mouse CRX. They had similar problems going to the big rubber a few years ago.

https://worldtimeattack.com/index.ph...even-mightier/

A lot of bodywork, tubbing, and geometry correction. Probably easier to do on an unlimited car.

Chilicharger665

iTrader: (2)

I think an NC would be the miata to use for both an LFX swap and the tire size requirements.

ThePass

iTrader: (3)

Very similar, actually. Just like Mighty Mouse we've been fighting at the front of the pack with the least power and the least tire, and just as they did I've concluded that as the field continues to get faster, to stay near the front I need to do everything I can to level the playing field in those two areas. As they found, there are plenty of hurdles to overcome, but they got faster in the end because they did it right. I hope to as well.

I had a chance to look over that car in detail last year.

blackzx3_13

+1 here. I've been to COTA for Super Lap both years (and will continue to go as long as they keep doing it, with dreams of running in it one day), but I've probably seen less than 10 "complete" unlimited laps. This past year was particularly disappointing, at least for unlimited builds. I go for the more club-level builds anyway. It seems like there are more than a few teams that are facing issues with the limited sizing in the spec tire.

/thread jack. I'm pumped to see Hyper next year at COTA! You guys need some merch. I'd buy a shirt and some stickers.

ThePass

iTrader: (3)

Detour from cutting up the chassis for a moment. After months of measuring, drawing, triple checking and revising drawings... parts are materializing to move the transmission project forward.

Got this picture from CNC of the adapter plate being born:



Less than 24 hours later I had it test fit to the motor, a couple final adjustments made, and now it's off to anodizing:



With the adapter here I was able to mock up the bellhousing to the motor for the first time and do some trimming on that so that it now mounts up:



And apparently Monday all the stars and planets were aligned because on that same day the custom flywheel arrived. This baby is CNCd from a single piece of chromoly, designed for a 7.25" twin plate clutch, with a welded ring gear and integral pilot bearing (So happy to have a pilot bearing after the MV5/7 design that doesn't have one). It's almost 10 lbs lighter than the 'lightweight' aluminum flywheel from Spec, and almost 20 lbs lighter than the factory flywheel.