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Discussion Starter #1
Well, I was thinking about rims again (easy to do when you're driving on a bent one:roll: ) and especially about my friend's SVT Contour (just an example, dont close the thread yet!) Not a torquey beast, but fun to drive. However, he got some 18" lead weights for the car last year. They're nice looking, but the car is a complete dog with them on. When he puts on his 15" steel snows, the car accelerates like a sports car again. He's seriously considering selling the big rims and getting some stock 16" SVT rims. I think this will help him out a lot. Why is this ford issue being posted in a 9-3 forum then, you say?

Well, lots of people buy new rims for their car, only to find that the car is much slower with them on. If companies tell anything about the performance of their rims, it is the weight and width. this really doesnt give an idea of the actual rotational force required to turn the wheel.

Take for example, 2 different 17" rims weighing 25 lbs a peice. Either one will have the same effect on acceleration if fitted to the same car, right? NO. If most of the mass of the wheel is closer to the center of the rim, it will take less torque to make it turn than if it is located on the outside radius. Simple physics saying that the torque arm is shorter for the weight on the wheel with more centered mass, minimizing what I think we called the 'moment' in college. My friend's wheels have a small center with thin spokes and lots of metal out near the tire, which weighs a lot itself. This is the worst possible setup IMHO.

So, buying a lighter wheel *could* still slow down your car, and you'll end up like my ford driving friend, though I doubt very much that his wheels were lighter. I think a wheel manufacturer should step up and make some really light wheels built in the best possible configuration.

And then they should perform a test that measures the amount of force to get the tire turning at a certain speed. Kind of like a dyno test, but reversed..

Then you could get a direct comparison of different wheels, knowing full well that getting this nicer looking wheel will slow you down a bit, but not enough
 

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Its more of an appearance issue rather than a performance issue.

I think people who put 18's 19's even 20's its to change the appearance of their vehicle.

I've always believed in this statement "rims make the car"! Rims do make and compliment the car!

But if your after performance definately stay 17" and under!

I'm a big fan of the 18" wheel and i have no problems keeping up and beating these other guys on the street!!:cheesy:
 

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The problem for us performance nuts is most rims are made for looks, not performance. So almost all of the rims that are made with performance in mind usually cost a fortune, generally because theyre forged, or use different materials, or they need more material near the outer rim to prevent bending. I wish there was a company which sold inexpensive performance based wheels :cry: .
 

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Discussion Starter #4
Yeah, It seems to me that any of the rims that are cheap enough for me to consider them are too cheap to even advertise weight.. Probably because they're embarassingly heavy...:roll: I went to the ATS site; they have a section called "light alloy wheels" AND STILL NO WEIGHTS!!!

Wheels are such a great opportunity to make a car accelerate faster and corner better.. Lower rotational weight, lower unsprung weight.... Really I can't think of a performance/comfort reason that you would not want lighter wheels.. the only problems are durability and expense; and appearance if you swing that way...

I dont. I bought my Viggen because I wanted a fast SAAB.. It's not my fault it came from the factory drop dead gorgeous:cheesy: But it looks like it does because of aerodynamics, form following function, to some extent at least...

Now I want light strong rims, like the kind that arent made of solder and crossed fingers:roll:

I think this 'wheel dyno test' would be a nice measurement, if you could make it in units people could easily understand and compare. Such as: If you had a car that went 0-60 with your stock 16" rims/tires in 6 seconds, and you switch to this tire/rim in 18", your new 0-60 will be approximately 8 seconds. You could calculate the load with both types of wheel, and the difference in load could be used to estimate the difference in acceleration..
 

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roadkil34 said:
The problem for us performance nuts is most rims are made for looks, not performance. So almost all of the rims that are made with performance in mind usually cost a fortune, generally because theyre forged, or use different materials, or they need more material near the outer rim to prevent bending. I wish there was a company which sold inexpensive performance based wheels :cry: .
wheels are not made for looks, there are 17 inch rims out there that weigh like 15lbs... i have held them in my own hands, people just pick the wrong rims for their cars

it has been mentioned here a million times that u r adding unsprung weight to the car
 

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Discussion Starter #8
ricot83 said:
wheels are not made for looks, there are 17 inch rims out there that weigh like 15lbs... i have held them in my own hands, people just pick the wrong rims for their cars

it has been mentioned here a million times that u r adding unsprung weight to the car
Really, 15lb 17" rims? Are they made for SAAB? Do they stay True? How much do they cost?

I suppose it probably has been mentioned a million times.. But I dont bother reading any threads about rims bigger than 18" so I would probably not have seen it. I dont care to make my car slower...

The main intent of this post was to mention the idea of actually testing the torque that different wheels require for the same performance. I personally would prefer quantitative data that my car wont slow down if I were to spend big bucks on wheels and tires...
 

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This month's Grassroots Motorsports has an ad in the front couple of pages for some ultralight racing wheels...I just remember the prices being inversely proportional to the weight, as in the lighter the wheel, the heavier the hit on your bank account.

And I think those ultralight wheels are fine for autocrossing or track racing on decently maintained surfaces, but I think they'd go home crying to mama after a spring in New England....
 

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Thats Why I love my BBS RK's only 17lbs. I am a big stickler for keeping unsprung weight at a minimum, and most people do not even realize what unsprung weight is. 13lbs 17inch Rims thats really cool, but being that my BBS cost a pretty penny I can't imagine what those cost.

Also Tires can make a difference as well. There are some farily heavy tires out there, and that combined with a really heavy rims can really make a car feel doggish.

However there are people out there that purley put Rims on a car for looks.
I say to each there own. For me I was lucky to find a set of Rims that I love the Looks of as well as being light weight and 8 inches wide.
 

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Anybody else remember 9-3 Mike's thread? It went on for like 4 pages, all to the point of if he should get 20's. People argued and argued until he said that he actually uses 17s (I think, maybe 18s) for his normal driving. This is my point!

Typically: Performance= 17 or less; Looks= 17 or bigger. Obviously this is general. But you get the idea.

So with that out of the way. Yes, unsprung weight is huge!!! I completely agree with all that you are saying. One of my big points with lighter wheels is longevity. I know the stock Viggen wheels are heavy and bend easy, but usually weight is paired with durability. So the lighter you go, usually more likely to bend.

That is why for me, unlike 9-3 Mike who has the 19s for show, and 17s for regular use. I would go with light weight 17s for track, and strong, maybe heavy, 18s for daily use. Its all what you do with your car.

But wheels definatly make the car!!!!!!!!!!

(I'm pretty sure I represented all that 9-3 Mike said, if not sorry. I just wanted to press my point, so if its not accurate, you still know what I mean.)
 

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ricot83 said:
wheels are not made for looks, there are 17 inch rims out there that weigh like 15lbs... i have held them in my own hands, people just pick the wrong rims for their cars

it has been mentioned here a million times that u r adding unsprung weight to the car

yeah but most wheels that size, or of any size for that matter, weigh more than that. Youre telling me wheels arent made for looks? then whats the point of "dubs" and dub deuces? or 19's on a civic? do people actually believe their car is going to perform and handle better with that type of lead weight on their car? You cant be serious that companies dont make wheels for looks. I doubt a ricer cares wheter his wheels weigh 15 pounds or 45 pounds a pop. but if its got that bling or that nice chrome, or the spinners of course, then theyll spring for it. Companies realize they can make money off that, and thats what they make, the cheapest way possible, which is heavy. There are companies which are exceptions though, such as Team Dynamics or something like that, where theyll make reasonably sized wheels, and sometimes theyre forged, for low weight, good weight distrobution, and good handling.

/rant
 

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roadkil is right. Probably 80-90% of aftermarket wheels kill performance. I work with a guy with a Chevy Silverado SS, he's got it cranked up with a supercharger and a whole list of stuff to about 680hp. (Dyno verified, don't go there!) The 0-60 time with 24" Lexanis was like a second slower than with the stock wheels. But the 24s looks amazing!!!!! The truck is black, btw. He was stunned when he found this out. So he bought some Volk racing 18s, mind you the stocks are 20s. So now he's got 18s for drags and 24s for street. He seems to be in good shape!!!
 
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