Wheel options: is there anything other than 6UL?
#21
The manufacturing quality control that Tirerack finds acceptable is not quite up to my standards. This spoke measured around 1/16" thinner than the the others, and the porosity right on the surface of the back face is not encouraging to me. I'm sure they are basically as safe as other gravity cast wheels of the same weight to size ratio, but I ended up sending it back and getting a set of 6UL 15x9 wheels....
Edit: to their credit, I should mention TR took it back and paid the return shipping, even though they said it wasn't defective, or any worse than any other wheel they sell under the TR Motorsports name.
Edit: to their credit, I should mention TR took it back and paid the return shipping, even though they said it wasn't defective, or any worse than any other wheel they sell under the TR Motorsports name.
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The price difference between the C3M and the 6UL is relatively small. The quality difference is somewhat larger.
#25
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For me, it's a matter of principal. They waited until 949 did all the hard work and proved that there was a market for a "good" Miata-specific wheel, then cloned the 6UL design and made a cheaper, heavier version with poorer quality control.
The price difference between the C3M and the 6UL is relatively small. The quality difference is somewhat larger.
The price difference between the C3M and the 6UL is relatively small. The quality difference is somewhat larger.
Remember the C3M is NOT the 6ul knockoff (the C1 is)...and the C3M is the only one they offer in 9", so the statement of copying the design is false.
The point is, the C3M is a legitimate second option. It is NOT as good of quality, and the cost vs quality might not be comparable to some, but it still works...and its not "copying."
---- THE MIATA IS A "COPY" OF THE LOTUS ELAN CONCEPT... GET OVER IT
/ rant
#26
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So I just learned something:
XXR Wheels is The Pursuit of Lightweight wheel
I guess they started out with some heavy wheels so they have nowhere to go but up (down) but honestly I never would have guessed that is what they were trying to make.
XXR Wheels is The Pursuit of Lightweight wheel
I guess they started out with some heavy wheels so they have nowhere to go but up (down) but honestly I never would have guessed that is what they were trying to make.
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---- THE MIATA IS A "COPY" OF THE LOTUS ELAN CONCEPT... GET OVER IT
For all intents and purposes, Mazda invented the the modem lightweight, inexpensive roadster in an era when the concept had been completely forgotten. Lotus, MG, Triumph, etc., had all abandoned the concept a decade or more earlier, and Mazda took a huge risk investing in a design concept for a market which, at the time, wasn't even know to exist.
If 949 had said "fuсk it, we're not interested in this anymore" and closed their doors, and then 15 years later TR had come along and said "Hey, I wonder if anybody might be ingested in a cheap 15x8 / 15x9 wheel these days? Let's invest a lot of money in designing one on the off chance that maybe people will buy it" then I wouldn't feel quite the same degree of annoyance towards them about it.
#33
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Important to acceleration and deceleration, yes it is very important.
Accelerate this stone wheel to 300rpm using 50hp.
Now accelerate this bicycle wheel to 300rpm with 50hp.
Now tell me which one would make it to the end of the longest straightaway first using the same powerplant?
Now, with the stock Miata brakes, bring each one to a stop from 300rpm.
Which one would need to start braking sooner to reach turn-in speed at the end of the straightaway using the stock Miata brakes?
Important? Yes.
Next exercise, imagine two Miatas going over a rough section in the track. One has 80lb wheels and tires on each corner and the other has 10lb wheels and tires on each corner. Let's say there is a 2 inch drop in the pavement that the car encounters in a corner followed by a two inch rise before leveling off (like turn 17 at Sebring). As the car is traveling about 75mph in that turn and the fall and rise occur quickly at that speed, which car's wheels will be able to more quickly respond to the drop and rise without losing contact with the concrete surface.
Which wheel's mass in motion, given the same shocks and springs, will be best able to change direction of motion -from down -to up -to level and maintain the contact patch to concrete connection for the greatest amount of time?
Which car's contact patch is doing a better job helping the car continue to turn through the unevenness of the track surface?
How helpful is a contact patch that is not in contact as often?
Is weight most important? Sometimes.
Is contact patch size most important? Sometimes.
Life is a series of trade offs.
So is racing. A blown big block Chevy would get my car down the straights faster but it wouldn't corner with a Spec Miata. A 18inch wide tire and wheel might stick like bubblegum in the corners but might accelerate more slowly in the straights and decelerate more slowly at the ends of the straights. There is a point of diminishing returns for anything and you have to figure out where that is through calculations and testing.
You are speaking in absolutes and I think that is unwise. It sounds like you are trolling.
#34
I was more trying to make a point that people will obsess over a pound or two difference between two wheels (like a 6ul vs a XXR or something) while you can gain/lose just as much rotating mass with tire choice and yet there's very little/no data on tire weights.
Edit: For example when I had my turbo Civic one drag slick mounted on one STEEL diamond racing wheel weighed 26lbs combined. I bet any road legal steel belted radial tire on even a super light wheel would weigh more. Just cause the only metal in the slick was the bead, so it was a very light tire.
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d
I was more trying to make a point that people will obsess over a pound or two difference between two wheels (like a 6ul vs a XXR or something) while you can gain/lose just as much rotating mass with tire choice and yet there's very little/no data on tire weights.
Edit: For example when I had my turbo Civic one drag slick mounted on one STEEL diamond racing wheel weighed 26lbs combined. I bet any road legal steel belted radial tire on even a super light wheel would weigh more.
I was more trying to make a point that people will obsess over a pound or two difference between two wheels (like a 6ul vs a XXR or something) while you can gain/lose just as much rotating mass with tire choice and yet there's very little/no data on tire weights.
Edit: For example when I had my turbo Civic one drag slick mounted on one STEEL diamond racing wheel weighed 26lbs combined. I bet any road legal steel belted radial tire on even a super light wheel would weigh more.
#37
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On topic I found these for the e30's and they don't look too bad, too bad they don't come in 9" wide
http://www.harrisonmotorsports.com/d...4x100-e30.html
#38
At any power at which you have enough power to spin the tires at will, the same is true for the weights in acceleration, except we count half of the weight savings, because the front wheels are still driven by the road, the power for that is derived from the engine of the car.
Is weight most important? Sometimes.
Is contact patch size most important? Sometimes.
Life is a series of trade offs.
So is racing. A blown big block Chevy would get my car down the straights faster but it wouldn't corner with a Spec Miata. A 18inch wide tire and wheel might stick like bubblegum in the corners but might accelerate more slowly in the straights and decelerate more slowly at the ends of the straights. There is a point of diminishing returns for anything and you have to figure out where that is through calculations and testing.
You are speaking in absolutes and I think that is unwise. It sounds like you are trolling.
Is contact patch size most important? Sometimes.
Life is a series of trade offs.
So is racing. A blown big block Chevy would get my car down the straights faster but it wouldn't corner with a Spec Miata. A 18inch wide tire and wheel might stick like bubblegum in the corners but might accelerate more slowly in the straights and decelerate more slowly at the ends of the straights. There is a point of diminishing returns for anything and you have to figure out where that is through calculations and testing.
You are speaking in absolutes and I think that is unwise. It sounds like you are trolling.
1.) You mention contact patch area like it is a function of tire size, with bigger tires having bigger contact patches. That's not actually true. Contact patch area is a strong function of tire pressure, and a weak function of sidewall stiffness. The contact patch area is basically the instantaneous corner load divided by the pressure in a bias ply. In a radial with stiff sidewalls, you can subtract a tiny bit from the slightly higher contact pressure right under the sidewall if the sidewalls are stiff enough. The advantage to wider/narrower and/or bigger/smaller diameter tires is way more complicated than just an increase in area, which you can achieve with a little lower inflation pressure.
2.) Reducing mass when there is no other trade off is always good, but there is almost always a trade off. The easy way of saying that sounds like an absolute. Sometimes it is worth more mass in a wheel just to get more stiffness, so there isn't camber loss occurring in the wheel back bell. I was responding to someone who sounded like he was advocating looking for the lightest tire as a starting point. If there was an RE-11 and a Star Spec both available in similar gearing, and one was lighter than the other, and I thought the lighter one would have just as much grip, I might pick it for being lighter. Probably I would still pick based on something else, like rain performance, or cost. The fact is it isn't like that. If the one that sticks better and costs less and has better gearing is 1 lb heavier, we easily pick the heavier tire if we know what we are doing and we want to go faster. It is almost never a good idea to pick the lightest option, unless we are picking it because it offers something else, and happens to be light. A toyo T1R that is the exact same diameter and tread width but lighter than an R1R is never going to be faster. That was my point. It isn't like there are equivalent options out there that are the same except one is lighter, or options where the other differences are overshadowed by weight. Lighter is better, as long as it doesn't compromise something that matters more, which is often everything else. All this based on timed events, not feel or pride or ride quality or anything subjective.
3.) I pretty much regret saying anything at this point, since my perspective is so far removed from what is average for this forum that I do sound like I am trolling, and I felt obligated to put the effort into a reply, even thought I'm not feeling like it will be well received.
4.) This is right in my area of professional expertise (the practical application of the theoretical side of solid mechanics and energy systems). If we were talking botany, or medicine, or something else I know nothing about, I wouldn't just state things I think like they are facts, because then they probably wouldn't be
#39
d
I was more trying to make a point that people will obsess over a pound or two difference between two wheels (like a 6ul vs a XXR or something) while you can gain/lose just as much rotating mass with tire choice and yet there's very little/no data on tire weights.
Edit: For example when I had my turbo Civic one drag slick mounted on one STEEL diamond racing wheel weighed 26lbs combined. I bet any road legal steel belted radial tire on even a super light wheel would weigh more. Just cause the only metal in the slick was the bead, so it was a very light tire.
I was more trying to make a point that people will obsess over a pound or two difference between two wheels (like a 6ul vs a XXR or something) while you can gain/lose just as much rotating mass with tire choice and yet there's very little/no data on tire weights.
Edit: For example when I had my turbo Civic one drag slick mounted on one STEEL diamond racing wheel weighed 26lbs combined. I bet any road legal steel belted radial tire on even a super light wheel would weigh more. Just cause the only metal in the slick was the bead, so it was a very light tire.
I started out replying because you said there is no data on tire weight. Most tire manufacturers publish tire weights. Often they have the data on their own individual websites. Tire rack for one compiles all that data neatly for us. You can look up pretty much any tire they carry and in the specs tab it will list the weights of each and every size of that particular tire.