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Discussion Starter #1
Has anybody that has upgraded theirs wheels weighed the old ones? Just wondering if they are light, or if I should be looking for some new wheels. Thanks,
 

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i'll look into if for you
 

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:shock: 41 lbs each, holy crap these thing are heavy. That means I better start looking into changing the wheels and tires. :wink:
 

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I'm no mechanical engineer, but the weight isn't really what you're concerned about. It's the mass (weight) distribution, right? You want less mass on the outer part of the wheel. I believe they have some sorta machine that can do those types of measurements by spinning the object. But I don't really know.....
:?
 

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I've heard that unsprung weight will affect acceleration the most. Like a 3 to 1 difference. I noticed a difference with the butt dyno on my 240sx. But having wider tires helps too I guess. I used SSR competitions on my last car. It was RWD, and had a different offset than the SRT, so I sold them with the car.
 

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for every 10 lbs of unsprung weight lost, it's equivilent to 100 lbs. of sprung weight lost. Do the math. )
 

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Just wanted to comment on the 41lb. weight. The tires themselves probably weigh anywhere from 21- 25 pounds( thats going off some different manufacturers websites for 205/50-17 tires, michelin doesn't list weights). So that would put the wheels at anywhere from 16-20 lbs. ea. which isn't great for a 17x6 rim but isn't really that bad either. Personally I would love to see about 12-14lbs. ea. but that wouldv'e probably taken a forged wheel to make the strength to weight ratio. And I don't think that really fits with dodges most performance for under 20 grand scenerio. I've been looking at the rota attack which is a knock off of one of the volk wheels. It's actually a 17x7.5 that only weighs like 16lbs but I don't think the offset will work with the srt4.
 

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Unsprung weight will make a difference in acceleration, handling, and in some cases braking.
 

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Unsprung weight makes a lot of difference in all handling aspects (body tilt during accel & braking included), but the acceleration difference ratio (similar to the 3:1 posted, so in effect the same) is due to the fact that it is rotating, not merely unsprung. This includes wheels, pulleys, flywheels, driveshafts, etc. etc. For rotating media, you want low weight, but you also want the weight as close to the center as possible (spin yourself in a chair).

VV
 

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Don't confuse unsprung weight with rotational weight. They can be the same thing but they aren't always. Rotational weight does have a greater affect on acceloration than static weight but the more common theory is more like 2:1 not 3:1 and definately not 10:1. It also makes a difference how far the weight is from the point of the center of rotation.

For example going from a 18" wheel that has its weight towards the rim to a 14" wheel that has its weight toward the hub will be more beneificial than going from a 18" wheel that has the weight closer to the hub and going to a 14" wheel that has its weight closer to the rim.

Rotaional weight that is also unsprung weight would be the wheel, tire, brake rotor and hub. The caliper, dust shield, upright or spindle and usually half of the lower control arm are also unsprung weight but are not rotational weight.

It is best to keep the sprung vs unsprung weight ratio as high as possible ( say 100 lbs of sprung weight for 1 lb of unsprung weight ) as this gives the best ride and handling especially on bumps without overly stiff springs and the shocks to control the high rate springs.

Rotational weight is also ( but not limited to ) all the accesorie pulleys, axles, driveshafts, clutch assembly and flywheel,balance shafts etc...Also remember that the benefit is magnified the lower the gear ratio.
 

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I guess I am a little slow typing as Vette Vert beat me to the puch by 2 mins. Hopefully it is clear enough between our two posts.
 

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Ihaterice said:
Just wanted to comment on the 41lb. weight. The tires themselves probably weigh anywhere from 21- 25 pounds( thats going off some different manufacturers websites for 205/50-17 tires, michelin doesn't list weights). So that would put the wheels at anywhere from 16-20 lbs. ea. which isn't great for a 17x6 rim but isn't really that bad either. Personally I would love to see about 12-14lbs. ea. but that wouldv'e probably taken a forged wheel to make the strength to weight ratio.
Come on! No 20K cars come with forged wheels. Hell most more expensive cars don't either.
Food for thought:
MazdaSpeed Protege wheel: 25lbs
SER SpecV wheel: 24lbs
Focus SVT wheel: 22.5-23lbs
Hyundai Tiburon GTV6 (17x7): 26lbs
Lancer Evolution (just for kicks): 16.5-17lbs :)
So the wheels being aroung 17lbs isnt really bad when you look at the other cars in the range (mind you, the evo wheels are 17x8 i think).
 

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I just wanted to clear something up, I wasn't saying that I expected it to come with forged wheels for 20g's. I said I wouldv'e loved to see the wheels at 12-14lbs which wouldv'e probably require forged wheels. Just like I wouldv'e loved to see 100 more hp and awd. Wanting something is not the same as expecting it. I understand the cost limitations put on dodge to get the vehicle on the road for under 20g. Personally I've never been happy with stock anything, I always want better, bigger, quicker, faster etc.
But I must admit dodge did a pretty good job of upgrading most of the things I normally would've bought through the aftermarket for this car. I don't think I wouldv'e purchased it if they hadn't. Peace. :D
 
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