I saw somebody asking another question about wheels and worrying over their relative weight.

The two perspectives are of course the rotating mass, and the unsprung weight.

There was a time when I was more interested in this stuff, but that's long over.

Don't get me wrong though. The simple physics of light weight cannot be denied. But they can be oversold.

Do you know how much unsprung weight you've got on each front corner of something like an Integra?

It's about 110 lbs.

And at the rear it's about 60 lbs.

You think about the nearly instantaneous acceleration of something weighing that much when you run it into a bump, and it looks like alot of energy.

So you save a few pounds with a light expensive wheel. Maybe you save 5 pounds by going to a light alloy caliper. You've still got about 100 lbs. That's still alot of energy. The benefit of your expenditure might be far more theoretical than perceptible.

Lightweight lugnuts? Puhleeze. "Oh - Anodized? Well, that's a different matter altogether!"

Scott, who nonetheless will continue to reduce mass whenever practical...whatever that means...

 

Aaron, who nonetheless will continue to reduce mass whenever practical...whatever that means...

 

-Jeremy, who bought 200 brand new shiny lugnuts at a cost of .24/ea

 

*BURP*

<------------Just finished 8 nuggets and waffle fries on his way to reducing the unsprung weight fraction.

 

light nuts 'just go with' lightweight wheels...

my wheels were the best preformance purchase I have made for 'my' car.... not that I have many preformance items.


you know you want to do it....
light weight nuts take you to the 'next' level.
http://www.we-todd-did-racing....D.jpg

 

Uh-oh!

Will! No..no..no....Not You Too!

Scott, for who'm this is like looking down and seeing that Will's feet point backward..."I didn't know he was an Alien"...

* Explanation: The Monkey's episode with Pat Paulson...

 

They got me too

http://www.we-todd-did-racing....D.jpg

Too bad they are not as stunna-riffic as will0rdz nutz

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">Not You Too!</TD></TR></TABLE>
yup.

Sadly they were 'included' when I purchased the wheels from their previous owner.
Daym that brother of mine and his selling tactics...

 

Will's not too blame, I threw those in with the wheels with he bought them from me, way back when.

 

I'm not really out to castigate, blame, stigmatize, or ridicule anyone.

"Yeah - Right!"

More seriously though - I've always looked at Alloy nutz with suspicion. I remember Victor had some though. And it looks like you guys have put lots of laps on them. No problemz eh?

Scott, who'z askeered of many things...especially threaded titanium fasteners...that's why I refuse to use any titanium on my car....well, that and the fact that I can't afford it....

 

i prefer to look at lighter wheels having less of a gyroscopic affect. too bad my larger, more heat capacitative rotors just added more gyroscopic affect than what was removed with the lighter wheel.

 

FWIW...

The difference between my 16lb MSWs and 11.5lb Hayashis at the end of a longish straight is rather consistently about 2mph. 2mph can easily be the difference between a pass under braking or a tuck in and follow.

How do I know this? Am I a Schumacheresque genius that can feel 1 or 2 mph difference on a straight?
Nah. Its simply a matter of all things being equal (draft, traffic, proper exit of turn 7...), with the Hayashis my shift light is on at the end of the Road Atlanta back straight. With the MSWs, it isn't.
&lt;shrug&gt;

Scott, who after noticing this little tidbit put "Panasports" on his ARRC to-do list.

 

cost &gt; benefit

 

I think it's a little more important than you are implying. Problem is you can't do much about getting it down in % terms, which doen't make it less important just because you can't do it (well perhaps it does). If you could reduce unsprung weight from 110 lbs to 55 lbs, you would have a large effect. Tire weight is always in the same range for a 225 on 15" rims, give or take, say 20 lbs. It is the most important as its mass is at the furthest away from the center. No changes can be made there. Wheel weight in a 15" depends on width, and you are looking at 13 lbs down to maybe 8 lbs for the most expensive ones. Only a 5 lb difference on the total, and tire plus wheel changes from 33 lbs to 28 lbs, and moment of inertia changes less than that since the tire radius is 12-13" while the rim radius is 7-7.5", so when you square them, the tire wins by several lengths. Then you have the disk, hub and axle rotating. No change can be made to the hub or axle weights, and disk is likely to be heavier than stock. Legend GS disk upgrade weighs 14.8 lbs, a couple more lbs than stock. Then you have the non-rotating stuff. upgrade to an NSX iron caliper that weighs 12 lbs, again a couple more lbs than stock. Buy some ALU calipers, to save some weight, maybe 5 lbs less than stock, but you have to decide if they are for stock disk, like Spoon, or for larger disk, like Stoptech or other. Then you add brake pad weight, and knuckle which are fully unsprung, but you can't change those. The lower A-arm is quite heavy, and you might be able to get a lighter one, as long as it can handle the torque. The upper A-arm is not very heavy, 4.5 lbs (about half un-sprung), so not much gain can be made there. Then spring is fairly fixed weight if you use a 7" one at 2.5" I.D., or maybe 2.25". Damper body can save a couple of lbs with an ALU one, and you could use an upside down one to reduce unsprung mass more than total mass. All in all it's going to be tough to get wider wheels and tires and bigger brakes and drop any unsprung weight at all over stock. It is going to cost a bundle. NSX has forged ALU suspension arms, as does the new RL. All in all you can get it down by 10 lbs. Is it worth a couple of tenths?

Maybe lug nuts are the secret. The again, if you could drop 50 % from the 2 front corners, it's going to be a lot faster. Just can't afford it.

 

Lugnuts matter a whole lot, if you're, you know, Juan Montoya. For the rest of us there are cheaper ways to loose unspring weight:

- Remove half the lug nuts on each wheel (if you have odd number, slightly more than half)

- Fill your tires with helium

- Drill holes in your brake rotors (not those weenie cast-in holes, I mean big-*** swiss cheese holes)

- Run lighter springs

- The weight of fasteners adds up fast. Replace them all with zip-ties.

- Why do all the work when the street can do it for you! Scrape your wheels against curbs whenever you get the chance, to remove heavy powedercoating

- Valve stem caps. Gone.

- Balanced wheels are for sissies. Chuck those wheel weights and reap the benefits.

- Shocks? Gone. We all know the spring does all the work anyway.

Of course the shock is only half-unspring weight. Actually, it isn't really half-unsprung, but if you take the inverse square of the first three digits of the serial number on the shock and multiply them by number of parking lights on the vehicle, you'll have wasted as much time as if you actually tried to figure it out.

 

Brakes? Suspension?

puss

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Angry Joe &raquo;</TD></TR><TR><TD CLASS="quote">Lugnuts matter a whole lot, if you're, you know, Juan Montoya. </TD></TR></TABLE>

The only thing Lightweight lugnuts are going to do for JPM is allow him to spin (coming down the front straightaway) a fraction of a second sooner than usual.

 

Every so often I get a chance to lift some real racing parts like wheels, uprights, and such, and I'm blown away by how light they can be.

Then I heft the stuff on a production car like one of ours, and I look at what small improvements can be made for modest dollars and I kinda shake my head.

Alot of it has to do with how and when we make our decisions.

Take Scott Giles' example for instance - that 2mph would be worth more right then during a race when faced with competition just a hair away than it would be thinking about it calmly over your morning Captain Crunch.

Scott, who makes all of his decisions Very Carefully...right up to the second I execute - that's when it always seems to go to hell...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">

The only thing Lightweight lugnuts are going to do for JPM is allow him to spin (coming down the front straightaway) a fraction of a second sooner than usual. </TD></TR></TABLE>

Okay bad example. Anyway Montoya has only one nut (per wheel)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">And it looks like you guys have put lots of laps on them. No problemz eh?</TD></TR></TABLE>
only problem (was it really?) was when I installed the GM ARP studs. I had to chase a tap thru them to clean out the threads/antiseze. Used a box in wrench and did it by hand... no hard twisting was needed.

purchased ~Nov. 2000
http://www.imagestation.com/pi...c.jpg
I took them over at/near ~Sept. 2002
I have put ~22,000 miles on them (14 events) (non-racer with street tires). Previous owner put about that much/many on them before I gained possession.
http://www.we-todd-did-racing....D.jpg


A ~9.74883 pound wheel feels 'much better' than a stock ITR wheel even under street conditions.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RR98ITR &raquo;</TD></TR><TR><TD CLASS="quote">Take Scott Giles' example for instance - that 2mph would be worth more right then during a race when faced with competition just a hair away than it would be thinking about it calmly over your morning Captain Crunch.
</TD></TR></TABLE>

Well, at least you seem to recognize that you are sick.
I hear that its the first step towards getting better.

Scott, who will support Scott during the tough times on his road to good health.

 

You're on the west coast tho. You're supposed to embrace all of the lightweight goodness FULLY! Oh. And make sure its JDM.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Catch 22 &raquo;</TD></TR><TR><TD CLASS="quote">
Scott, who will support Scott during the tough times on his road to good health.</TD></TR></TABLE>

You'll have to excuse my friend Scott. The business we're in is fairly slow right now, so I'm guessing this allows him more time to think about light nutz.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by johng &raquo;</TD></TR><TR><TD CLASS="quote">

The business we're in is fairly slow right now
</TD></TR></TABLE>

I never really thought about it, but it does make sense.
It figures that the housewives have less time and money for the male exotic dancers when the kids are home from school.

You guys should see if the Hyperfest folks will let you wear some marble bags and hit each other with sticks.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Catch 22 &raquo;</TD></TR><TR><TD CLASS="quote">
Scott, who will support Scott during the tough times on his road to good health.</TD></TR></TABLE>

I keep seeing this phrase pop up: "That's Good to Know!"

Scott, who thinks maybe he IS getting better...I just bought another motor...that's a Good Thing right? I figure if more horsepower doesn't make me go faster then I'll know I'm not the problem.....no, no, it Does make sense, think about it some more...