widened steelie question
#2
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The problem will be the weight and how poorly Miatas react to heavy wheels.
Your car will be considerably slower. Your car will be more uncomfortable to drive/ride in. Your car will handle worse in corners.
There are several lightweight choices in steel racing wheels, especially in 13", but 1.8 brakes won't clear the 13s. The 15s exist but are a little heavier than the 13s. They exist because many types of racing don't allow aluminum wheels.
Bottom line is it is your car and you can do whatever you want with it.
Your car will be considerably slower. Your car will be more uncomfortable to drive/ride in. Your car will handle worse in corners.
There are several lightweight choices in steel racing wheels, especially in 13", but 1.8 brakes won't clear the 13s. The 15s exist but are a little heavier than the 13s. They exist because many types of racing don't allow aluminum wheels.
Bottom line is it is your car and you can do whatever you want with it.
#4
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The rotational weigh of the wheels counts about three times as much against you for accelerating and braking as static weight of the rest of the car does. Any of the rotating mass of the drivetrain, wheels, and brakes will be critical for acceleration, especially in an underpowered car. Heavier is much slower. Lighter is better.
#14
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Here's one. You can put info in this spreadsheet on your tires and wheels or look at what is already in there as an example. Concentrate on the changes in results at "Tire + Wheel Edge Weighted" and "Chassis Weight Equivalent" at the bottom right for the four wheel total difference.
http://the-welters.com/racing/rotational.xls
There is some background info here :
http://the-welters.com/racing/rotational.html
I recommend Googling lots of different sources for a better understanding.
Anecdotal:
Cliff_J
Jul13-04, 03:05 PM
Here's just a single example but relevant to your question. On the Speed channel is a show called "Sports Car Revolution" where they have a project Acura RSX. When they went to larger diameter discs that were two pounds lighter and larger diameter wheels with the same overall weight, they lost 12 horsepower. They're using a dynojet which uses the acceleration of heavy drums to measure horsepower. Their source concluded that even though the overall mass of the brakes and wheel/tire combination was less, the distribution at a larger radius accounted for the 7% loss in power.
Chester - if you needed to pry open a crate, would you prefer a 6" crowbar or a 3' crowbar?
Same for flywheels. Think back to some pictures of the really old-school stuff and you'll see some flywheels where its basically spokes supporting a large ring on the outside, all the mass is concentrated at as large a diameter as possible.
For a wheel, one could have a very heavy center section and very light rim, the other a super-light center section and heavier rim. As a flywheel they could work out to be either way. I hope the flywheel metaphor works for you, its pretty simple to think that if it stores energy it must have energy input into it to get it up to speed. And if you're using engine power to spin up the flywheel, that leaves less power to accelerate the car.
Cliff
One of the reasons the weight of a wheel and tire hurt acceleration so much is that it must be accelerated twice, both forward through space and rotationally. It likewise hinders braking.
http://the-welters.com/racing/rotational.xls
There is some background info here :
http://the-welters.com/racing/rotational.html
I recommend Googling lots of different sources for a better understanding.
Anecdotal:
Cliff_J
Jul13-04, 03:05 PM
Here's just a single example but relevant to your question. On the Speed channel is a show called "Sports Car Revolution" where they have a project Acura RSX. When they went to larger diameter discs that were two pounds lighter and larger diameter wheels with the same overall weight, they lost 12 horsepower. They're using a dynojet which uses the acceleration of heavy drums to measure horsepower. Their source concluded that even though the overall mass of the brakes and wheel/tire combination was less, the distribution at a larger radius accounted for the 7% loss in power.
Chester - if you needed to pry open a crate, would you prefer a 6" crowbar or a 3' crowbar?
Same for flywheels. Think back to some pictures of the really old-school stuff and you'll see some flywheels where its basically spokes supporting a large ring on the outside, all the mass is concentrated at as large a diameter as possible.
For a wheel, one could have a very heavy center section and very light rim, the other a super-light center section and heavier rim. As a flywheel they could work out to be either way. I hope the flywheel metaphor works for you, its pretty simple to think that if it stores energy it must have energy input into it to get it up to speed. And if you're using engine power to spin up the flywheel, that leaves less power to accelerate the car.
Cliff
One of the reasons the weight of a wheel and tire hurt acceleration so much is that it must be accelerated twice, both forward through space and rotationally. It likewise hinders braking.
Last edited by sixshooter; 05-04-2011 at 03:50 PM.
#15
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A little light mathematics exploring the subject with regard to automobiles:
http://hpwizard.com/rotational-inertia.html
http://hpwizard.com/rotational-inertia.html
#16
A little light mathematics exploring the subject with regard to automobiles:
http://hpwizard.com/rotational-inertia.html
http://hpwizard.com/rotational-inertia.html
#20
because 9 out of 10 outsiders/strangers that hop on here to sell their **** without being part of the community are low life pieces of **** that scammed tons of people on here. We like to buy/sell within the community of honest/helpful forum members and friends and generally have low opinions of n00bs until you prove otherwise. That takes time.