Looking for power loss RESULTS from 20" wheels
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From: Windsor/Storrs, CT
Looking for power loss RESULTS from 20" wheels
I used the search but couldn't find the specific info I am looking for.
I am trying to gauge the amount of power lost from having 20 inch wheels, more specifically versus 19 inch wheels. I know that weight has everything to do with it so for the purposes here just consider average range weights, no $6k ultra light weight ones. Anyone have a dyno or actual quantifiable numbers for the loss of power?
I do NOT want to start another endless debate about wheel sizes I am just looking for this specific information, and I know both sizes are more visual oriented rather than performance, I am just looking for some results and to get an idea about the expected power loss going from 19 to 20 inch wheels from those of you who have ACTUALLY driven/ridden in both. I basically need to make a purchase decision and I need to hear others' experiences, not just what they've heard, as in I am looking for either A) it really makes no difference its only 10-15 lbs total all around for 20's over 19's, its nothing or B) it makes a hell of a difference, it feels a lot slower don't bother if you want your car to still pull
That's all, Thanks in advance
I am trying to gauge the amount of power lost from having 20 inch wheels, more specifically versus 19 inch wheels. I know that weight has everything to do with it so for the purposes here just consider average range weights, no $6k ultra light weight ones. Anyone have a dyno or actual quantifiable numbers for the loss of power?
I do NOT want to start another endless debate about wheel sizes I am just looking for this specific information, and I know both sizes are more visual oriented rather than performance, I am just looking for some results and to get an idea about the expected power loss going from 19 to 20 inch wheels from those of you who have ACTUALLY driven/ridden in both. I basically need to make a purchase decision and I need to hear others' experiences, not just what they've heard, as in I am looking for either A) it really makes no difference its only 10-15 lbs total all around for 20's over 19's, its nothing or B) it makes a hell of a difference, it feels a lot slower don't bother if you want your car to still pull
That's all, Thanks in advance
Ok ic your point.. Me personally I did the nismo 18/19 on my car and lemme tell you its a Disappointment in how much slower the car got.. For the *******s below me saying its forged wheels blah blah its makes a big difference in my eyes going bigger.... Its looks nice, handles better with the tires but cost me some ponies downlow
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I know it isn't the original question, but out of curiosity what about when going from your stock rims to your 20's, did you notice a big difference?
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Let me put it this way....
I used to have a set of 19's (not the ones I have now) that weighed the same as my stock 17" Enthusiast wheels. While back I had to put my 17's back on and my butt dyno felt a huge effin difference. Rotational inertia ftl. My next set of wheels now that my AME's are ruined are going to be 18X10 in all four corners Advan RS's. 18-20 lbs FTW. Honestly....it's quite a difference when you start adding pounds and diameter.
I used to have a set of 19's (not the ones I have now) that weighed the same as my stock 17" Enthusiast wheels. While back I had to put my 17's back on and my butt dyno felt a huge effin difference. Rotational inertia ftl. My next set of wheels now that my AME's are ruined are going to be 18X10 in all four corners Advan RS's. 18-20 lbs FTW. Honestly....it's quite a difference when you start adding pounds and diameter.
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The size of the rim is more of a factor than weight is. A 20" rim has the weight farther from the center and will take more power to overcome the intertia from such a large wheel. A heavier 19" wheel is better than a lighter 20" wheel (or the same depending). Weight is a factor, but not as big a factor as size. If we could fit 15" wheels on our cars even the heaviest crappiest 15" would way out accelerate any 19" or 20" wheel by a huge margin.
Put a weight on a piece of string and with about 6 inches of string let out spin it around in a circle. Pretty easy with a flick of your wrist. Now go out to 6 feet of sring and try that same flick of the wrist to spin it around. Not going to happen. You would need a lot more effort to make up the inertia of such a long string because the weight is so far from the center. A heavier weight also is a factor, but not as much as the overall size of the wheel.
Thats why trucks with 26" wheels are SOOOO slow. So much weight overall and such a huge wheel, it's a double whammy. Even if those 26"s were 20lbs each it would still be a huge amount of inertia to overcome.
So with only 1" difference between 19's and 20's does it make a difference? Well yeah and no. If you drive on the street and are not tracking the car (on those wheels) then it dosen't matter. Thats like saying you bought a pop-charger for the power. 5hp is not noticable and isn't gonna do anyting for you. But that pop-charger with exhaust and a plenum spacer and chip etc yeah for sure. So if you are just rollin on the street, getting a 20" wheel won't really matter honestly. Nobody here is racing on the street (right?) so really the weight shouldn't be a big deal.
Personally I didn't want a 20" because they are heavier and larger plus you get into a 30 series tire which is not very much side wall. The ride will be rougher and a lot better chance of bending a rim with a 20 inch wheel because of the thin tires. To each their own.
Put a weight on a piece of string and with about 6 inches of string let out spin it around in a circle. Pretty easy with a flick of your wrist. Now go out to 6 feet of sring and try that same flick of the wrist to spin it around. Not going to happen. You would need a lot more effort to make up the inertia of such a long string because the weight is so far from the center. A heavier weight also is a factor, but not as much as the overall size of the wheel.
Thats why trucks with 26" wheels are SOOOO slow. So much weight overall and such a huge wheel, it's a double whammy. Even if those 26"s were 20lbs each it would still be a huge amount of inertia to overcome.
So with only 1" difference between 19's and 20's does it make a difference? Well yeah and no. If you drive on the street and are not tracking the car (on those wheels) then it dosen't matter. Thats like saying you bought a pop-charger for the power. 5hp is not noticable and isn't gonna do anyting for you. But that pop-charger with exhaust and a plenum spacer and chip etc yeah for sure. So if you are just rollin on the street, getting a 20" wheel won't really matter honestly. Nobody here is racing on the street (right?) so really the weight shouldn't be a big deal.
Personally I didn't want a 20" because they are heavier and larger plus you get into a 30 series tire which is not very much side wall. The ride will be rougher and a lot better chance of bending a rim with a 20 inch wheel because of the thin tires. To each their own.
Last edited by 350z-Jim; Mar 6, 2009 at 03:44 AM.
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Thanks for all the replies, I am getting a lot of good input
No I will not be tracking the car, it's just my daily and I don't plan on ever doing it either, and I don't race on the street, so I am not worried about that. I am just worried about turning my quick z into a slug because I wanted 20 inch rollers instead of 19's. I am not going smaller than 19, so I guess you are right in the fact that the difference from 19 to 20 is like the popcharger comparison. I do worry about the bending issue, I live in CT, the roads can be bad sometimes especially after the winter with potholes, and I have bent a rim before. I had 19's on my last car and I have learned to drive carefully and have been issue free for awhile now... But when you think about how much difference from the 19 inch tire with a 35 series sidewall vs a 20 inch with a 30 series sidewall... it really doesn't make much difference, I believe that what matters more is the fact that it is larger and weaker... My other concern is that I am dropped on coilovers, and I will have less room to lower the car won't I if I go with a 20 inch wheel...
No I will not be tracking the car, it's just my daily and I don't plan on ever doing it either, and I don't race on the street, so I am not worried about that. I am just worried about turning my quick z into a slug because I wanted 20 inch rollers instead of 19's. I am not going smaller than 19, so I guess you are right in the fact that the difference from 19 to 20 is like the popcharger comparison. I do worry about the bending issue, I live in CT, the roads can be bad sometimes especially after the winter with potholes, and I have bent a rim before. I had 19's on my last car and I have learned to drive carefully and have been issue free for awhile now... But when you think about how much difference from the 19 inch tire with a 35 series sidewall vs a 20 inch with a 30 series sidewall... it really doesn't make much difference, I believe that what matters more is the fact that it is larger and weaker... My other concern is that I am dropped on coilovers, and I will have less room to lower the car won't I if I go with a 20 inch wheel...
The size of the rim is more of a factor than weight is. A 20" rim has the weight farther from the center and will take more power to overcome the intertia from such a large wheel. A heavier 19" wheel is better than a lighter 20" wheel (or the same depending). Weight is a factor, but not as big a factor as size. If we could fit 15" wheels on our cars even the heaviest crappiest 15" would way out accelerate any 19" or 20" wheel by a huge margin.
Put a weight on a piece of string and with about 6 inches of string let out spin it around in a circle. Pretty easy with a flick of your wrist. Now go out to 6 feet of sring and try that same flick of the wrist to spin it around. Not going to happen. You would need a lot more effort to make up the inertia of such a long string because the weight is so far from the center. A heavier weight also is a factor, but not as much as the overall size of the wheel.
Thats why trucks with 26" wheels are SOOOO slow. So much weight overall and such a huge wheel, it's a double whammy. Even if those 26"s were 20lbs each it would still be a huge amount of inertia to overcome.
So with only 1" difference between 19's and 20's does it make a difference? Well yeah and no. If you drive on the street and are not tracking the car (on those wheels) then it dosen't matter. Thats like saying you bought a pop-charger for the power. 5hp is not noticable and isn't gonna do anyting for you. But that pop-charger with exhaust and a plenum spacer and chip etc yeah for sure. So if you are just rollin on the street, getting a 20" wheel won't really matter honestly. Nobody here is racing on the street (right?) so really the weight shouldn't be a big deal.
.
Put a weight on a piece of string and with about 6 inches of string let out spin it around in a circle. Pretty easy with a flick of your wrist. Now go out to 6 feet of sring and try that same flick of the wrist to spin it around. Not going to happen. You would need a lot more effort to make up the inertia of such a long string because the weight is so far from the center. A heavier weight also is a factor, but not as much as the overall size of the wheel.
Thats why trucks with 26" wheels are SOOOO slow. So much weight overall and such a huge wheel, it's a double whammy. Even if those 26"s were 20lbs each it would still be a huge amount of inertia to overcome.
So with only 1" difference between 19's and 20's does it make a difference? Well yeah and no. If you drive on the street and are not tracking the car (on those wheels) then it dosen't matter. Thats like saying you bought a pop-charger for the power. 5hp is not noticable and isn't gonna do anyting for you. But that pop-charger with exhaust and a plenum spacer and chip etc yeah for sure. So if you are just rollin on the street, getting a 20" wheel won't really matter honestly. Nobody here is racing on the street (right?) so really the weight shouldn't be a big deal.
.
good info
you can never take david's comments serious....lol. i have 20's and i came from the stock 18's. i didnt really notice a difference at all except the road noise. but damn they look good when you dont lower it. (dont want to here in okc...terrible roads and usually crap all over em) but i may end up lowering anyways lol.
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I just put on my lightweight semi-solid forged (~21 lbs each) 19" SSR Comp-H's yesterday which I upgraded from stock base 17s. So far I'd go as far to say that my car actually noticeably performs better, but I'm going to contribute that to the new summer performance tires that I got for my 19s since my 17s were running on crappy Yokohama YK520 all-season tires. Had I gone with the same tires, I'm not sure how large of a difference the extra wheel diameter would have made but from driving my car around on lightweight 19s I don't think the difference would be very big, if even noticeable. Not sure if it helps to add, but I do drive aggressively when the opportunity arises (which, in a small town where traffic and blind areas aren't a big issue that I visit almost every week, is fairly often 
).
My main point is: I don't think you'll lose noticeable performance going from a heavy 17 to a lighter 19 inch wheel/tire combo assuming you can keep the overall diameter roughly the same or only a few mm larger (tires can weigh more than wheels, especially in the case of light performance wheels). I cannot vouch for 20s, however.
).My main point is: I don't think you'll lose noticeable performance going from a heavy 17 to a lighter 19 inch wheel/tire combo assuming you can keep the overall diameter roughly the same or only a few mm larger (tires can weigh more than wheels, especially in the case of light performance wheels). I cannot vouch for 20s, however.
Last edited by RedSled; Mar 6, 2009 at 05:27 PM.
Remember tire weight plays a big part too, especially since they're the furthest away from the hub. I had the 18" '03 Rays, and put on 19" Enkei's (also lightweight) and noticed no power loss. 1" of aluminum compared to 1" of tire sidewall there isn't a huge weight difference.
If you add some ugly, heavy chrome to the mix though, then you'll notice a definite loss of acceleration.
Remember "an object in motion tends to stay in motion yada yada" so the heavier your wheels, the worse your acceleration and braking will be. You will suffer exponentially. The faster your speed, the greater the resulting loss of "power." So while from 0-60mph, you may be only 3/4 a car length behind.... this may translate to multiple car lengths at higher speeds assuming the two cars are otherwise equal except for their wheel/tire weights.
If you add some ugly, heavy chrome to the mix though, then you'll notice a definite loss of acceleration.
Remember "an object in motion tends to stay in motion yada yada" so the heavier your wheels, the worse your acceleration and braking will be. You will suffer exponentially. The faster your speed, the greater the resulting loss of "power." So while from 0-60mph, you may be only 3/4 a car length behind.... this may translate to multiple car lengths at higher speeds assuming the two cars are otherwise equal except for their wheel/tire weights.
