To answer the original question, back in the day, mag wheels, as they were called, were very expensive and only found on fancy sports cars. However, today they're made in Asia for practically peanuts and it's imperative to save as much weight as possible to get every last bit of fuel economy. The fact that they look better than steel wheels with hubcaps is an added bonus. Yeah, I was [censored] off too when I started seeing wheels on minivans and SUVs that looked as good as those on my Camaro.
Stock Steel Vs Stock Aluminum Wheels
- Thread starter AstroTurf
- Start date
- Status
Originally Posted By: Oldyellr
Originally Posted By: Hokiefyd
NASCAR uses steel wheels.
They also use carburators and solid rear axles.
Actually NASCAR is a "special case" especially when it comes to wheels. Those steel wheels are only 9.5" wide and run oversize tires that bulge out a couple of inches on each side. That's what makes those cars so "squirelly" and the racing so, umm, "exciting".
All that is right. I was just pointing out that they use steel wheels because the statement was made that "all" race cars use aluminum alloy.
Word has it they're going to fuel injection next year or the year after.
Originally Posted By: Hokiefyd
NASCAR uses steel wheels.
They also use carburators and solid rear axles.
Actually NASCAR is a "special case" especially when it comes to wheels. Those steel wheels are only 9.5" wide and run oversize tires that bulge out a couple of inches on each side. That's what makes those cars so "squirelly" and the racing so, umm, "exciting".
All that is right. I was just pointing out that they use steel wheels because the statement was made that "all" race cars use aluminum alloy.
Word has it they're going to fuel injection next year or the year after.
Guys,
I got new tires on 5/25. Riding on the Steelies and my Mpg was in the toilet. I happened upon the Aluminum Rims on 6/04 and changed over to them.
It seems that my Mpg is a little better than before the new tires. Handling has changed for the better IMO.
It is like training for a marathon in work boots, Then running the race in sneakers.
I am pleased with the change.
Thanks, Jim
PS Is there a formula for sprung vs unsprung weight reduction?
I got new tires on 5/25. Riding on the Steelies and my Mpg was in the toilet. I happened upon the Aluminum Rims on 6/04 and changed over to them.
It seems that my Mpg is a little better than before the new tires. Handling has changed for the better IMO.
It is like training for a marathon in work boots, Then running the race in sneakers.
I am pleased with the change.
Thanks, Jim
PS Is there a formula for sprung vs unsprung weight reduction?
If anything the fuel economy difference is likely due to different trend depth and size of tires. On the same metal wheels, my mom's corolla feels like a turtle when it was switched from worn out Chinese T rated 175 65 14 to Dunlop SPA2 H rated 195 60 14. Both were about 3/32" left, but the difference is noticeable.
Originally Posted By: AstroTurf
I got new tires on 5/25. Riding on the Steelies and my Mpg was in the toilet. I happened upon the Aluminum Rims on 6/04 and changed over to them.
EDIT: Should have read... New Tires on 4/25, Aluminum Rim changeover on 5/04.
Sorry
I got new tires on 5/25. Riding on the Steelies and my Mpg was in the toilet. I happened upon the Aluminum Rims on 6/04 and changed over to them.
EDIT: Should have read... New Tires on 4/25, Aluminum Rim changeover on 5/04.
Sorry
Originally Posted By: PandaBear
Most stock aluminum wheel are durable enough to withstand normal pot holes.
I wonder what a normal Silicon Valley pothole looks like. I dented an aluminum wheel rim, so the tire lost its air, on a pothole. This was a pothole in a place that has deep-freeze/thaw cycles. I had to get a new wheel. Steel is more durable, but it can rust (cosmetic) if you scrape the paint.
Most stock aluminum wheel are durable enough to withstand normal pot holes.
I wonder what a normal Silicon Valley pothole looks like. I dented an aluminum wheel rim, so the tire lost its air, on a pothole. This was a pothole in a place that has deep-freeze/thaw cycles. I had to get a new wheel. Steel is more durable, but it can rust (cosmetic) if you scrape the paint.
I don't know the pothole size in North Cal, but in my area if the pothole is deeper than 1/2" that you can fell while driving over it then people will complaint and it will be repaired in less than a week. That why many vehicles in So Cal has paper thin tires, some as low as 30-35 series, and sustain no damage to either expensive alloy wheels or tires.
Originally Posted By: Hokiefyd
Originally Posted By: Oldyellr
Originally Posted By: Hokiefyd
NASCAR uses steel wheels.
They also use carburators and solid rear axles.
Actually NASCAR is a "special case" especially when it comes to wheels. Those steel wheels are only 9.5" wide and run oversize tires that bulge out a couple of inches on each side. That's what makes those cars so "squirelly" and the racing so, umm, "exciting".
All that is right. I was just pointing out that they use steel wheels because the statement was made that "all" race cars use aluminum alloy.
Word has it they're going to fuel injection next year or the year after.
I think most oval racing uses steel wheels or atleast one on the front right. The near constant left turning plus the bumping with other cars, makes light alloy wheels not a great choice.
Originally Posted By: Oldyellr
Originally Posted By: Hokiefyd
NASCAR uses steel wheels.
They also use carburators and solid rear axles.
Actually NASCAR is a "special case" especially when it comes to wheels. Those steel wheels are only 9.5" wide and run oversize tires that bulge out a couple of inches on each side. That's what makes those cars so "squirelly" and the racing so, umm, "exciting".
All that is right. I was just pointing out that they use steel wheels because the statement was made that "all" race cars use aluminum alloy.
Word has it they're going to fuel injection next year or the year after.
I think most oval racing uses steel wheels or atleast one on the front right. The near constant left turning plus the bumping with other cars, makes light alloy wheels not a great choice.
Originally Posted By: AstroTurf
PS Is there a formula for sprung vs unsprung weight reduction?
The total inertia of rotating wheel mass is equivalent to 1.5 times its mass for a solid disc and 2.0 times its mass for a thin ring. So it's somewhere between that.
If you dropped 40 pounds off your wheels, it's probably equivalent to about 70 pounds in terms of acceleration and braking, but still only 40 in terms of rolling resistance. So rolling resistance will be down about 1%, energy required to accelerate and brake will be down about 2%, and, of course, wind resistance will not be affected. So I'd guess the total effect on fuel economy would be about 1%.
That is a fair bit of mass though. I think you'd feel the difference in your suspension.
PS Is there a formula for sprung vs unsprung weight reduction?
The total inertia of rotating wheel mass is equivalent to 1.5 times its mass for a solid disc and 2.0 times its mass for a thin ring. So it's somewhere between that.
If you dropped 40 pounds off your wheels, it's probably equivalent to about 70 pounds in terms of acceleration and braking, but still only 40 in terms of rolling resistance. So rolling resistance will be down about 1%, energy required to accelerate and brake will be down about 2%, and, of course, wind resistance will not be affected. So I'd guess the total effect on fuel economy would be about 1%.
That is a fair bit of mass though. I think you'd feel the difference in your suspension.
Originally Posted By: rpn453
Originally Posted By: AstroTurf
PS Is there a formula for sprung vs unsprung weight reduction?
The total inertia of rotating wheel mass is equivalent to 1.5 times its mass for a solid disc and 2.0 times its mass for a thin ring. So it's somewhere between that.
If you dropped 40 pounds off your wheels, it's probably equivalent to about 70 pounds in terms of acceleration and braking, but still only 40 in terms of rolling resistance. So rolling resistance will be down about 1%, energy required to accelerate and brake will be down about 2%, and, of course, wind resistance will not be affected. So I'd guess the total effect on fuel economy would be about 1%.
That is a fair bit of mass though. I think you'd feel the difference in your suspension.
Kewl, and Thanks...
Now I don't have to go on that Diet my wife has been buggin me about. LOLz
Thanks Again, Jim
Originally Posted By: AstroTurf
PS Is there a formula for sprung vs unsprung weight reduction?
The total inertia of rotating wheel mass is equivalent to 1.5 times its mass for a solid disc and 2.0 times its mass for a thin ring. So it's somewhere between that.
If you dropped 40 pounds off your wheels, it's probably equivalent to about 70 pounds in terms of acceleration and braking, but still only 40 in terms of rolling resistance. So rolling resistance will be down about 1%, energy required to accelerate and brake will be down about 2%, and, of course, wind resistance will not be affected. So I'd guess the total effect on fuel economy would be about 1%.
That is a fair bit of mass though. I think you'd feel the difference in your suspension.
Kewl, and Thanks...
Now I don't have to go on that Diet my wife has been buggin me about. LOLz
Thanks Again, Jim
Originally Posted By: rpn453
......but still only 40 in terms of rolling resistance.........
Sorry, but rolling resistance (a steady state property) is unaffected by the wheel.
The only time wheel weight comes into the picture is during accelleration and braking, and from a fuel consumption point of view, the wheels only consume fuel when they are accelerating. In braking they are losing energy, but they do not consume more fuel during that time.
......but still only 40 in terms of rolling resistance.........
Sorry, but rolling resistance (a steady state property) is unaffected by the wheel.
The only time wheel weight comes into the picture is during accelleration and braking, and from a fuel consumption point of view, the wheels only consume fuel when they are accelerating. In braking they are losing energy, but they do not consume more fuel during that time.
Last edited:
Originally Posted By: CapriRacer
Sorry, but rolling resistance (a steady state property) is unaffected by the wheel.
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Sorry, but rolling resistance (a steady state property) is unaffected by the wheel.
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Originally Posted By: rpn453
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
Originally Posted By: CapriRacer
Originally Posted By: rpn453
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
Okie Dokie then...
How bout the unsprung mass reduction.
What effect does that have?
Thanks, Jim
Originally Posted By: rpn453
It seems hard to believe that vehicle mass doesn't affect rolling resistance. I assumed that rolling resistance was approximately proportional to mass. That may be off, but it must have some effect.
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
Okie Dokie then...
How bout the unsprung mass reduction.
What effect does that have?
Thanks, Jim
During acceleration, weight in the wheels has between 1x and 2x of the effect of the same amount of weight that is not rotating, depending how far from the rotation axis the weight is. The average effect of the weight would have an effect of maybe 1.6x the same weight on the chassis.
Originally Posted By: Carbon
During acceleration, weight in the wheels has between 1x and 2x of the effect of the same amount of weight that is not rotating, depending how far from the rotation axis the weight is. The average effect of the weight would have an effect of maybe 1.6x the same weight on the chassis.
Thanks Carbon
Jim
During acceleration, weight in the wheels has between 1x and 2x of the effect of the same amount of weight that is not rotating, depending how far from the rotation axis the weight is. The average effect of the weight would have an effect of maybe 1.6x the same weight on the chassis.
Thanks Carbon
Jim
Originally Posted By: CapriRacer
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
Does rolling resistance of automotive tires deviate significantly from the basic formula where rolling resistance force is proportional to the normal force (weight, in this case)? If not, a 1% increase in mass should translate to a 1% increase in rolling resistance.
Yes, more mass would add to a tire's rolling resistance (assuming the inflation pressure and tire size remain the same), but the effect is so small compared to the mass of the vehicle that its effect can be ignored.
Does rolling resistance of automotive tires deviate significantly from the basic formula where rolling resistance force is proportional to the normal force (weight, in this case)? If not, a 1% increase in mass should translate to a 1% increase in rolling resistance.
Originally Posted By: rpn453
Does rolling resistance of automotive tires deviate significantly from the basic formula where rolling resistance force is proportional to the normal force (weight, in this case)? If not, a 1% increase in mass should translate to a 1% increase in rolling resistance.
Last Sept I attended a tire conference where Bruce Lambilotte from Smithers Scientific Services gave a presntation where he showed that RR was NOT proportional to the normal force - and he showed examples where is went both ways. I couldn't see the scale of the data, so I couldn't judge if the effect was small or not - but I suspect it is small enough to ignore.
That was the long way of saying - Yes!, a 1% change in normal load would result in a 1% change in RR.
Oh and don't foegt that the affect RR has on fuel economy is somewhere about 15% (varies depending on the situation), so a 1% change in RR results in a mere fraction of a precent change in fuel economy.
Does rolling resistance of automotive tires deviate significantly from the basic formula where rolling resistance force is proportional to the normal force (weight, in this case)? If not, a 1% increase in mass should translate to a 1% increase in rolling resistance.
Last Sept I attended a tire conference where Bruce Lambilotte from Smithers Scientific Services gave a presntation where he showed that RR was NOT proportional to the normal force - and he showed examples where is went both ways. I couldn't see the scale of the data, so I couldn't judge if the effect was small or not - but I suspect it is small enough to ignore.
That was the long way of saying - Yes!, a 1% change in normal load would result in a 1% change in RR.
Oh and don't foegt that the affect RR has on fuel economy is somewhere about 15% (varies depending on the situation), so a 1% change in RR results in a mere fraction of a precent change in fuel economy.
Last edited:
Originally Posted By: CapriRacer
Last Sept I attended a tire conference where Bruce Lambilotte from Smithers Scientific Services gave a presntation where he showed that RR was NOT proportional to the normal force - and he showed examples where is went both ways. I couldn't see the scale of the data, so I couldn't judge if the effect was small or not - but I suspect it is small enough to ignore.
That was the long way of saying - Yes!, a 1% change in normal load would result in a 1% change in RR.
Oh and don't foegt that the affect RR has on fuel economy is somewhere about 15% (varies depending on the situation), so a 1% change in RR results in a mere fraction of a precent change in fuel economy.
What does this mean when it comes to "low rolling resistance" tires, as compared to other tires of the same class and size that are not LRR? Are the fuel economy benefits small enough and insignificant enough to ignore for most but the die-hard hypermilers?
Last Sept I attended a tire conference where Bruce Lambilotte from Smithers Scientific Services gave a presntation where he showed that RR was NOT proportional to the normal force - and he showed examples where is went both ways. I couldn't see the scale of the data, so I couldn't judge if the effect was small or not - but I suspect it is small enough to ignore.
That was the long way of saying - Yes!, a 1% change in normal load would result in a 1% change in RR.
Oh and don't foegt that the affect RR has on fuel economy is somewhere about 15% (varies depending on the situation), so a 1% change in RR results in a mere fraction of a precent change in fuel economy.
What does this mean when it comes to "low rolling resistance" tires, as compared to other tires of the same class and size that are not LRR? Are the fuel economy benefits small enough and insignificant enough to ignore for most but the die-hard hypermilers?
Originally Posted By: weebl
What does this mean when it comes to "low rolling resistance" tires, as compared to other tires of the same class and size that are not LRR? Are the fuel economy benefits small enough and insignificant enough to ignore for most but the die-hard hypermilers?
First, let's define LRR. It means ...... ah ...... Mmmmmmm ..... Oh ..... whatever someone says it means. Some take LRR to mean low compared to all tires - and some take it to mean lower than comparable tires.
Considering that Rolling Resistance, Traction, and Treadwear form a technology triangle - and you can't improve one property without sacrificing at least one of the other properties - then LRR is probably best understood as a difference in compromise where RR is improved and then some sort of balance is achieved for the other properties.
But the above paragraph is an over simplifcation of a very complex issue - and it is possible to achieve improved RR with very little loss of other properties. HOWEVER, this is NOT the way it usually turns out.
http://www.tirerack.com/tires/tests/Tire...us+Technology_1
Notice how different the tires perform.
But there can be a 60% difference in RR between tires - albeit with a similar change in those other 2 properties. I am sure folks would notice a difference of 60%!
But the effect RR has on fuel economy depends on the driving condition for each individual driver. A driver who has to live in stop and go traffic is probably not going to see much, if any, improvement, where a driver with a long commute on an interstate is probably going to see a significant improvment.
So it comes down to this: Is YOUR situation such that the improvement in RR is going to be felt strongly enough to overcome the Traction / Treadwear compromise - and I don't know the answer to THAT!
What does this mean when it comes to "low rolling resistance" tires, as compared to other tires of the same class and size that are not LRR? Are the fuel economy benefits small enough and insignificant enough to ignore for most but the die-hard hypermilers?
First, let's define LRR. It means ...... ah ...... Mmmmmmm ..... Oh ..... whatever someone says it means. Some take LRR to mean low compared to all tires - and some take it to mean lower than comparable tires.
Considering that Rolling Resistance, Traction, and Treadwear form a technology triangle - and you can't improve one property without sacrificing at least one of the other properties - then LRR is probably best understood as a difference in compromise where RR is improved and then some sort of balance is achieved for the other properties.
But the above paragraph is an over simplifcation of a very complex issue - and it is possible to achieve improved RR with very little loss of other properties. HOWEVER, this is NOT the way it usually turns out.
http://www.tirerack.com/tires/tests/Tire...us+Technology_1
Notice how different the tires perform.
But there can be a 60% difference in RR between tires - albeit with a similar change in those other 2 properties. I am sure folks would notice a difference of 60%!
But the effect RR has on fuel economy depends on the driving condition for each individual driver. A driver who has to live in stop and go traffic is probably not going to see much, if any, improvement, where a driver with a long commute on an interstate is probably going to see a significant improvment.
So it comes down to this: Is YOUR situation such that the improvement in RR is going to be felt strongly enough to overcome the Traction / Treadwear compromise - and I don't know the answer to THAT!
Last edited:
- Status
Similar threads
- Locked
