Is rim weight a critical factor?
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From: Stockholm, Sweden
C200 Kompressor
Is rim weight a critical factor?
Hi.
I'm in the market for a new set of rims for my W203. I've seen lots of threads discussing the importance of getting light rims (to decrease the unsprung weight). Why is this so important?
The rims I've been looking at is AMG Monblock II, ATP (AT Italia) Flash and ATP Benzis. I saw on www.tirerack.com that AT Italia (ATP Flash is offered, but how about ATP Benzis. I live in Europe and they are probably named differently here, but I couldn't find any similar looking rim in the "upgrade garage".
Can someone please explain why rim weight is important and provide me with weight figures for the following rims:
Thanks in advance!
An image of the ATP Benzis
I'm in the market for a new set of rims for my W203. I've seen lots of threads discussing the importance of getting light rims (to decrease the unsprung weight). Why is this so important?
The rims I've been looking at is AMG Monblock II, ATP (AT Italia) Flash and ATP Benzis. I saw on www.tirerack.com that AT Italia (ATP Flash is offered, but how about ATP Benzis. I live in Europe and they are probably named differently here, but I couldn't find any similar looking rim in the "upgrade garage".
Can someone please explain why rim weight is important and provide me with weight figures for the following rims:
- AT Italia Benzis (18x8)
- AT Italia Flash (18x8)
- AMG Monoblock II (18x8)
Thanks in advance!
An image of the ATP Benzis
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1996 C36 AMG, 1995 Volvo 850 Turbowagon
something called unsprung weight. in a nut shell, sprung weight is weight of vehicle that is supported by the suspension. unsprung weight is weight of the suspension itself (e.g. wheels, springs, shocks, etc.). the more unsprung weight there is, the harder the suspension has to work. hence rim weight is important. as the suspension to move up and down, it needs to compensate for it's own weight. momentum is mass times acceleration; so the less weight, the easier it is for the suspension to move up and down. hope that helps.
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Thanks alot for your reply Steve S!
Ok now I've got they "physics" around my question, but how will for a heavy rim affect the performance of the car, like acceleration, top speed or handling. I now understand that the suspention has to work harder with a heavier rim, but it this really a bad thing (I the sense that one should avoid a heavier rim). Will for example the suspention wear much quicker etc.?
Ok now I've got they "physics" around my question, but how will for a heavy rim affect the performance of the car, like acceleration, top speed or handling. I now understand that the suspention has to work harder with a heavier rim, but it this really a bad thing (I the sense that one should avoid a heavier rim). Will for example the suspention wear much quicker etc.?
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1996 C36 AMG, 1995 Volvo 850 Turbowagon
n/p
in real world? no...not really, u don't really have to worry too much about weight. most people do it for the looks . weight is therefore a secondary concern...unless u want to take ur car to the race track, where weight is everything, including the weight of the rim. of course, less weight is better. think about it, if u have a heavier wheel, that means the engine has to do just that little extra to start spinning the wheel so it can transfer the power to the ground.
for everyday use, and i assume u're going for the killer look on these 18" (17" should be quite enough to extract the great handling from a small car like the c200k), then you shouldn't have to worry too much about the weight. just use the weights as a guide if can't choose between the 3 by design (which, unfortunately, i don't have).
. weight is therefore a secondary concern...unless u want to take ur car to the race track, where weight is everything, including the weight of the rim. of course, less weight is better. think about it, if u have a heavier wheel, that means the engine has to do just that little extra to start spinning the wheel so it can transfer the power to the ground.for everyday use, and i assume u're going for the killer look on these 18" (17" should be quite enough to extract the great handling from a small car like the c200k), then you shouldn't have to worry too much about the weight. just use the weights as a guide if can't choose between the 3 by design (which, unfortunately, i don't have).
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From: Stockholm, Sweden
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Thank you!
I'm very pleased with both of your answers. My pimary purpose for a wheel upgrade would not be to decrease lap-times on a race track. I'm mainly interested in the looks. On the other hand, I wouldn't like to bargain to much of the performance (hence the original question). I will now, like you recommended, consider rim-weight a secondary concern.
Thanks again for all your help
I'm very pleased with both of your answers.
My pimary purpose for a wheel upgrade would not be to decrease lap-times on a race track. I'm mainly interested in the looks. On the other hand, I wouldn't like to bargain to much of the performance (hence the original question). I will now, like you recommended, consider rim-weight a secondary concern. Thanks again for all your help
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Re: n/p
Originally posted by steve s
in real world? no...not really, u don't really have to worry too much about weight. most people do it for the looks . weight is therefore a secondary concern...unless u want to take ur car to the race track, where weight is everything, including the weight of the rim. of course, less weight is better. think about it, if u have a heavier wheel, that means the engine has to do just that little extra to start spinning the wheel so it can transfer the power to the ground.
for everyday use, and i assume u're going for the killer look on these 18" (17" should be quite enough to extract the great handling from a small car like the c200k), then you shouldn't have to worry too much about the weight. just use the weights as a guide if can't choose between the 3 by design (which, unfortunately, i don't have).
in real world? no...not really, u don't really have to worry too much about weight. most people do it for the looks
. weight is therefore a secondary concern...unless u want to take ur car to the race track, where weight is everything, including the weight of the rim. of course, less weight is better. think about it, if u have a heavier wheel, that means the engine has to do just that little extra to start spinning the wheel so it can transfer the power to the ground.for everyday use, and i assume u're going for the killer look on these 18" (17" should be quite enough to extract the great handling from a small car like the c200k), then you shouldn't have to worry too much about the weight. just use the weights as a guide if can't choose between the 3 by design (which, unfortunately, i don't have).
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From: Bay Area, CA
I believe so. There is a website out there that posts wheel weights... if I can rememember where I saw it, I'll post it. Otherwise, just ask the company you are buying from about the wheel weight. Keep in mind that some of the light wheels out there are light because they aren't that strong. I would recommend going with a forged (as opposed to cast) wheel if you are looking for a combination of strength and light weight. Also keep in mind that I am driving a car that puts out over 480 hp and 450lb/ft of torque..... performance is first on my priority list. I think most drivers wouldn't care about the marginal perfromance differences a 12lb difference in wheel weight can make.
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M3 Cab
i think someone once posted that every pound of additional usnprung weight added equates to an approximate 2hp loss. so for sleestack, changing from Brabus to BBS would have slapped back on an estimated 24hp per wheel.
i know when i had my winter 15's on my a4 the car felt faster than when i ran my summer 17's. we'll see what happens when i get my 19's which may be lighter than the amg monoblock 18's. i will measure each wheel as i put them on and post the comparo.
i know when i had my winter 15's on my a4 the car felt faster than when i ran my summer 17's. we'll see what happens when i get my 19's which may be lighter than the amg monoblock 18's. i will measure each wheel as i put them on and post the comparo.
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Originally posted by oresama99
i think someone once posted that every pound of additional usnprung weight added equates to an approximate 2hp loss. so for sleestack, changing from Brabus to BBS would have slapped back on an estimated 24hp per wheel.
i know when i had my winter 15's on my a4 the car felt faster than when i ran my summer 17's. we'll see what happens when i get my 19's which may be lighter than the amg monoblock 18's. i will measure each wheel as i put them on and post the comparo.
i think someone once posted that every pound of additional usnprung weight added equates to an approximate 2hp loss. so for sleestack, changing from Brabus to BBS would have slapped back on an estimated 24hp per wheel.
i know when i had my winter 15's on my a4 the car felt faster than when i ran my summer 17's. we'll see what happens when i get my 19's which may be lighter than the amg monoblock 18's. i will measure each wheel as i put them on and post the comparo.
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From: PHILIPPINES
07' ML350
just had my 18" carlssons installed for almost a week now, and i dont c any difference in acceleration compared to my stock 16". The car doesnt lean as much, however the ride is bumpier than stock. So going bak to my question....what is the minimum recommentded tire pressure for 225/40zr18?????????????????
