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Two 15x9's?
Ok so this is awkward. A while back, during planning for our new gen 5 line, we determined that the big 11.75x1.25 AFCO/Wilwood/Stoptech BBK's wouldn't fit behind our previous generation 15x9 6UL. So we set it aside and decided to make the new 15x9 a Coto to increase brake clearance. The Coto is the same spoke pattern as the 6UL but with the spokes extending to the front flange instead of attaching at the drop center. In basic terms: 6UL= lip, Coto = no lip.
So we're plugging away on the 15x9 Coto design for the past month or so. Unbeknownst to me, John (our engineer) was secretly creating a new-from-scratch 6UL design to also clear the 11.75x1.25. After getting both the Coto and 6UL to the point where he could run FEA on them, we found the 6UL was significantly lighter at the same stress values (strength). That's intuitive as the spoke is shorter and less cantilevered. The Coto ends up with a bit more headroom in case anyone ever tries an even fatter caliper than existing BBK's but that's future proofing that no one really needs.
We had been telling folks the new 15x9 would be a Coto, but.. maybe not.
How the gen 5 15x9 6UL will be different than all previous 15x9 6UL's.
The lip on the old 15x9 and 15x10 was the same size, about twice the width of the 15x8. The G5 15x9 6UL would have a much smaller lip, the same size as our new 15x8. The spokes on the old 15x10 were a bit more concave than any other 6UL. The G5 15x9 6UL would have a similar concave spoke profile, more concave than the previous 15x9. So a subtle but important difference. While some folks don't need the clearance and want the wider lip of the old wheel, it does not make sense to make an entirely new mold just for that version.
Coto?
The 6UL still polls well, we still love it. But the Coto design is preferred by many and the longer spokes look damn hot.
Miataturbo
We're not publishing this info anywhere else so y'all get a rare chance to influence the outcome. We're leaning towards keeping the Coto in reserve for the higher offset 17-19" 5 lug designs that require massive brake clearance.
So, we submit the Coto and 6UL design studies for your perusal, love, acceptance, rejection, rebuke, admiration, ridicule..
I previously commented on your wheel thread about how the COTO's look good but share a lot of similarities to Jongbloed wheels if you are squinting at them. Yeah, yeah, I get that COTO's are more advanced in many ways and do look different, but the resemblance is still there.
In comparison, the 6UL design has always been something that looked good on many cars and was uniquely yours. Fix the strength shortcomings of early gen wheels with the due diligence you've been doing and I still think its a great looking lightweight wheel.
I enjoy the look of both but everything equal I'd choose the concave styling of the COTO over the lip of the 6UL on the basis of nothing more than personal preference. That is why I chose my Jongbloed 15x10's over the 6UL 15x10's when I had the choice. If I was in your shoes from a business man's perspective though, I'd be offering the product that is more unique and unlike other wheel options, so for that reason I voted 6UL.
I agree with Padlock. For me it's 6ul no question, in fact, this post has me postponing a wheel purchase of a certain 15.x9.5 wheel right now until closer to spring to see what you come up with. A modern 15x9 6ul that would clear my 1.25 afco boxmount kit, especially if it has addressed some of the weaknesses, would be a no brainer. And the pricing, at least looking at your 15x8 6ul pricing already, should be competitive enough that I'd buy a set for sure, even if I still go with the aforementioned 15x9.5's on the track the 6ul has always been my "dream wheel", and it was the hardest decision to make when shopping brake upgrades that I would lose them.
Just my $.02, I personally find the spoke to the edges of the wheel undesirable vs something like a 6ul. Though I will admit the way you made the Coto spokes flush with the rim of the wheel instead of protruding like the advanti's (and others) made it acceptable for me and I was still considering those for my 2nd wheelset.
I voted the 6ULs because they're lighter, there's "more sexy" in them due to the additional details, they DON'T look like Jongbloed rims, and the spokes are recessed from the lip so will not get any gutter rush.
I love my current 6UL 15x8s but WANT 15x9s too.
I'll be buying your KamaCoto 15x9s if you end up NOT producing the 15x9 6ULs.
Surprised to see that I’m one of two to vote for the Coto.
It was a tough decision. I like them both. And honestly, for a track-only wheel, performance trumps everything else (this would be my use).
I like the look of the Coto. It’s novel. If you release it in 15x9 first, everyone will instantly know I’m running baller 9” wide wheels and not limp-wristed 8” wheels. That’s very important to my manhood.
There’s actually a bit of an idea in there. Reserve the 9 and 10” widths for the Coto. Makes the wide ones special.
Whatever you decide, I’ll probably be buying a set. I say probably only because I’m a little short on funds right now and have some car-b-q to fix…
It may have something to do with when I got into Miatas, but NA/NB Miata = 6UL for me. The Coto is a great looking wheel, but has a 'contemporary' feel that would be great on an ND, but is out of place on an earlier Miata. Save the Coto for the 17"+ wheels and keep the 15s 6ULs. In the less subjective category, I do like the recessed spokes of the 6UL for practical reasons.
I really like the 9" 6UL pictured, but honestly may not be a buyer. My next set of race wheels are likely to be 15x10" (not 100% on that, though), and the street car is sticking with 8s...
Big lips look better on NA and NB since it makes wheel look smaller. Which I think looks better. On ND or Lotus elise the Cota would look great makes wheel look larger. I hope both wheel models come on sizes for elise. 15x8 and 17x9. Looks like Cota is available for elise.
I welcome the addition of 15x9.5 for those of us with NAs that dont want to pull fenders even more.
And good color choices.
When will we see some pictures of wheels on cars Emilio?
I voted 6ul as they look easier to clean, but the only wheel I'd replace my K1's with is the Sanger. Coto will sell well if that's what you choose to produce.
Spokes are still recessed on Coto so there's no greater chance of race rash until you've broken the wheel.
Really appreciate everyone's input. Thank you for posting and not just voting! Sharing your thoughts about the wheel is every bit as valuable as simply stating your preferences.
Not really surprised to see 6UL win, especially within this community. Probably won't be the last time we ask either though
At this stage it's looking like the first Coto will be the S2000 fitment. We have room for big brake clearance and a lip on NC/86 fitment wheels.
While I understand why basically all modern wheels have pushed the spokes to the edge of the wheel, I really miss wheels with recessed faces and deep lips. I'll take small lips if that's all I can get.
So.. assuming we do get a 15x9 6ul.. what is the best guess ETA? Just trying to gauge so I can hold off on a wheel purchase if they are coming in the spring.
11-17-2023, 05:29 PM
15x9 design studies
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