B
Body Roll
CompUser said:
I'd say if he hits an unmarked open manhole in the roadway
the steel rims probably won't make much of a difference.
But on a pothole ridden roads they might.
I'd say if he hits an unmarked open manhole in the roadway
the steel rims probably won't make much of a difference.
But on a pothole ridden roads they might.
Y
y_p_w
Jirí Lejsek said:
Sure I thought about it. These rules are often set up to
prevent entrants from simply outspending each other for
performance benefits. Sometimes they're set up a certain
way because the sanctioning bodies are old-fashioned. I
brought this up on rec.autos.tech, and some of the racers
there said they only used them because the rules forced
them to use steel wheels. The sense I got was that they
would go with aluminum wheels if the rules allowed them.
They also said that the lighter weight steel racing wheels
tend to bend easily and weren't repairable like heavier
weight street-legal steel wheels. BTW - Bassett has a
street legal 15" wheel that weighs a whopping 24 lbs.
NASCAR requires steel bodies even though fiberglass or
carbon fiber would be lighter. They require a cast iron
block engine with pushrods and carburetors. They also
require steel wheels without wheel covers. You're not
going to tell me that these are used because they
represent the best performance, are you? They require
these things because they're dinosaurs when it comes to
technological advances.
Formula 1 is probably the most advanced racing category
in the world, and they have been allowed to use light
alloy wheels for over 50 years. BBS supplies alloy
wheels for several Formula 1 teams:
<http://www.bbs-usa.com/index.php?id=681>
J
Jiøí Lejsek
They simply catched you. This is typical marketing article. They speek about
advantages of larger rims a smaller profile tyres as it would be advantages
of alloy wheels.
They present one example and make conclusion that alloy wheels are "much
lighter than steel wheels". This is simply not true.
y_p_w wanted some specefic data fromme, so I provide some:
1) TOYOTA Carina E
a) winter wheels: 32 lbs (orig. steel rim 6x14 + Brigestone Blizzak LM 20
185/65 R14 ~70%)
b) summer wheels: 36,5 lbs (some Mangels alloy rim 7x15 + Bridgestone
Potenza RE 720 195/55 R15 ~70%)
2) SUBARU Impreza WRX
a) winter wheels: 36,5 lbs (Impreza steel rim 6,5x16 + Semperit Speed Grip
205/55 R16 almost new ~90%)
b) summer wheels: 36,5 lbs (Original gold alloy rim 7x17 + Bridgestone
Potenza RE 050A 215/45 R17 ~70%)
Summer and winter wheels have the same overall diameter for every car.
(Do the steel weighs more in America? ;-) )
advantages of larger rims a smaller profile tyres as it would be advantages
of alloy wheels.
They present one example and make conclusion that alloy wheels are "much
lighter than steel wheels". This is simply not true.
y_p_w wanted some specefic data fromme, so I provide some:
1) TOYOTA Carina E
a) winter wheels: 32 lbs (orig. steel rim 6x14 + Brigestone Blizzak LM 20
185/65 R14 ~70%)
b) summer wheels: 36,5 lbs (some Mangels alloy rim 7x15 + Bridgestone
Potenza RE 720 195/55 R15 ~70%)
2) SUBARU Impreza WRX
a) winter wheels: 36,5 lbs (Impreza steel rim 6,5x16 + Semperit Speed Grip
205/55 R16 almost new ~90%)
b) summer wheels: 36,5 lbs (Original gold alloy rim 7x17 + Bridgestone
Potenza RE 050A 215/45 R17 ~70%)
Summer and winter wheels have the same overall diameter for every car.
(Do the steel weighs more in America? ;-) )
J
Jirí Lejsek
I think this is also about security.
If the steel is good enough for racing, so it should be more than sufficient
for normal use.
See my second entry.
If the steel is good enough for racing, so it should be more than sufficient
for normal use.
See my second entry.
C
CompUser
....and restrictor plates, too...so by jiri's
logic, we should all restrict our intakes for
better performance.
Doesn't Subaru's WRC run on some of those
heavier-than-steel BBS alloy rims also?
It's a shame they can't afford some decent steel
rims, eh?
C
CompUser
(e-mail address removed) says...> y_p_w wanted
some specefic data fromme, so I provide some:
You're **including tire weights**, and using
**different diameter & width** wheels (6" vs 7"
widths, 14" vs 15").
Same thing again, tho in this case, the wider
tire and bigger alloy wheel weigh the same as the
narrower steel combo. Ooops...alloy that's
bigger AND lighter
Yup.
some specefic data fromme, so I provide some:
You're **including tire weights**, and using
**different diameter & width** wheels (6" vs 7"
widths, 14" vs 15").
Same thing again, tho in this case, the wider
tire and bigger alloy wheel weigh the same as the
narrower steel combo. Ooops...alloy that's
bigger AND lighter
Yup.
M
Mark T.B. Carroll
Jiøà Lejsek said:
And what about Formula 1? Did they catch them too? Steel wheels are
perfectly legal under Formula 1 regulations, as I understand them.
-- Mark
Y
y_p_w
Jirí Lejsek said:
Of course street-legal steel rims are fine for normal use. That's not
what anyone is arguing here. The question is whether or not there
are any benefits to aluminum or magnesium alloy wheels. The
typical entry-level OEM alloy wheel is lighter/stiffer and transfers
heat better than the typical OEM stamped steel wheel. It's very
hard to get a street-legal steel wheel that's lighter than what's
currently available. However - there are lightweight aluminum and
magnesium alloy wheels that are considerably lighter than any
equivalent-sized steel wheel, yet street legal.
B
bugalugs
I think the point to be taken from the weights Jiøà Lejsek provided
was that the marketing hype about less unsprung weight was just that.
Hype.
The <normal punter> buys a car with steel wheels and standard tyres
decides that he wants alloys and 'one' of the selling points is this
unsprung weight. But then goes for a wider low profile tyre and the only
advantage is an extra inch in width, less pounds per sq inch on the road
and the ability to produce blue smoke sooner.
(My daughter-n-husband run a wheel/tyre shop and their target market is
the boyracer type)
was that the marketing hype about less unsprung weight was just that.
Hype.
The <normal punter> buys a car with steel wheels and standard tyres
decides that he wants alloys and 'one' of the selling points is this
unsprung weight. But then goes for a wider low profile tyre and the only
advantage is an extra inch in width, less pounds per sq inch on the road
and the ability to produce blue smoke sooner.
(My daughter-n-husband run a wheel/tyre shop and their target market is
the boyracer type)
R
Ray
Jiøí Lejsek said:
uh, but you're weighing the wheel and tire together.
(www.tirerack.com)
using your example: (BFG Gforce sport)
205/55 R16 -> 23 pounds for the tire
215/45 R17 -> 21 pounds for the tire.
and so, your steel wheel is 2 pounds heavier if the overall weight is
the same.
to compare wheels on a 2002 Subaru Legacy L wagon... (my car)
a 15x6 alloy goes as low as 13.5 pounds per wheel
I'm sure a stock steelie is more than 13.5 lbs.
maybe someone who's got one can weigh theirs...
Ray
R
Ray
yeah, I guess that's why cars like Vettes and Vipers all come with bigbugalugs said:
fat tires, just for looks. And those silly F1 guys, what do they know?
Y
y_p_w
Ray said:
<http://www.superhonda.com/tech/wheel_weights.html>
Again - one person got lots of people to send him weights of
several OEM and aftermarket wheel weight. The Legacy (year
wasn't mentioned) 15x6 stamped steel wheel was 19.5 lbs. The
same-sized Subaru OEM cast aluminum wheels by Enkei and
Topy were 16 and 18 lbs respectively. I have no doubt that it's
possible to make an extremely heavy aluminum wheel if no care
is taken to shave weight. However - the large majority of OEM
alloy wheels are lighter than the same sized steel counterparts,
in addition to being more rigid.
I don't know what Jiri's problem is. No matter what anyone shows
him or is able to demonstrate, he toes the line that steel is better.
For any practical consideration, aluminum and magnesium alloy are
better, albeit at a greater expense. I can't think of any racing
category where steel would be preferred wheel material if aluminum
or magnesium were allowed.
B
Body Roll
Sooner? With WIDER tires? Tell us what you smoke.bugalugs said:
Riiiiight. And the option of wider rear wheels/tires on Carrera is
tailored
for morons in their 40s with over $70k in their pockets also.
Y
y_p_w
bugalugs said:
I prefer the apples to apples comparison of equivalent size wheels
and tires. The original Mazda Miata came with 14" steel or aluminum
alloy wheels. The aluminum wheels didn't really have that boy racer
look either, but they weighed 12.3 lbs compared to the 18 lbs of the
steel version. That's a case (one among many) where a reasonable
application of alloy wheels is clearly superior to steel.
Larger rims with lower profile tires can actually weigh less in total
thann smaller, narrower steel rim, higher profile tire combinations.
You then get the advantage of better dry grip and improved steering
response. A bigger contact patch will reduce the chances of that
puff of blue smoke.
L
Lord Foul
Ray said:
Are you reading your own data? The summer tire is two pounds lighter,
and since the overall weight is the same, that means the alloy wheel is
two pounds heavier than the steel wheel, not two pounds lighter.
Again read your own data. In the example above, a 16 inch steel wheel
and tire weighs 36.5 pounds. Subtract the weight of your 23 pound
example tire, and you're left with 13.5 pounds. So a 16 inch steel wheel
is about as light as your 15 inch alloy wheel.
Make no mistake, you can buy extremely light alloy wheels. But you will
spend lots of money to do so, and risk destroying a wheel every time you
hit a deep pothole. Most people buy much more durable and less expensive
alloy wheels. These wheels are usually just as heavy as steel wheels.
Their primary advantage is that they look a lot nicer than steel wheels.
B
bugalugs
y_p_w said:
I thought it was the other way around.
If you had X amount of weight applied to the ground through a tyre
contact area Y then the any turning force applied tothe wheels would
propel the vehicle forward. But if the turning force exceeded the
friction between the wheel and the road the tyres would break traction
and spin. If you then widen the wheel you increase the size of the
contact patch that would reduce the pounds per square inch in contact
with the road. You apply the same amount of force to the same vehicle
weight then with a lesser pounds per square inch the tyres would
exceeded the friction between the wheel and the road the tyres would
break traction sooner.
Less weight per sq inch to prevent spinning.
Dunno, My maths are a little rusty :>)
Y
y_p_w
bugalugs said:
Well - I do remember high school physics, where in a perfect
friction world, contact area didn't matter as much as the
coefficient of friction. However - the real world isn't
theoretical physics, and megabuck cars have wide and tall
tires that don't easily break away into a cloud of smoking
rubber.
I don't see open cockpit cars using narrow tires, or
spinning their tires in a cloud of burning rubber. They
use really wide tires and seem to know what they're doing.
Y
y_p_w
Lord said:
However - the comparison is between a wider and taller alloy
wheel.
I can't imagine a street legal 15x6 steel wheel weighs
13.5 lbs. The lists I saw (where wheels were weight
without tires) were between 18-24 lbs.
Again - the stock 16x6.5 WRX wheels weigh 16.5 lbs, which
compares favorably with the 19 lbs. I can't figure out
what's going on with all those calculations, but here's
an actual list of Subaru Impreza wheels:
<http://wac.addr.com/auto/obs/wheels.html>
15x6 Impreza OEM steel: 19.5 lbs
16x6.5 WRX OEM aluminum alloy: 16.5 lbs
The stock 16" WRX wheel is plenty strong. They're not
superlight, but they are lighter than the corresponding
steel wheel. I know that steel wheels can take more abuse
and are easier to repair. However - the fact that steel
flexes more isn't an overall performance benefit.
N
nobody >
y_p_w said:
Severe off-road truck racing is still primarily "steel wheel" territory.
If you've ever seen a bent rim "fixed" with a 20# sledgehammer, you'd
know why. Any alloy would break under boulder slams like these dudes do.
Y
y_p_w
nobody said:
Certainly that makes sense. I guess a heavy steel wheel
would be more in the "bend not break" mold. However -
that's completely different than the stresses encountered
on pavement.
However - I can't imagine any racetrack use where steel
would be an advantage. Like I said - NASCAR mandates all
sorts of outdated technologies because they're dinosaurs.