in fact the weight in the wheels affected double of the weight inside the car (a factor of 0,0057 s/kg to 0,096 s/kg). Additionally unsprung weight makes suspension work harder in bumps meaning that a stiffer suspension is needed resting comfort and also driveability. you create very good content, thanks for it
Okay - so this is a GREAT test as it gives an idea of how the weight of a tyre & rim(wider, thicker, larger)affect acceleration(mileage, handling, etc)... BUT it's 50% unfair, because only 2 wheels got additional weight... All 4 wheels should have received extra weight for the test to be representative of the debate between Rotational Weight vs Static Weight - as even though the front wheels don't drive the car(in your case - GREAT looking car by the way), it still takes(more)energy to rotate them when they are heavier... So the actual times you would get would be worse than the 6,65 etc...🤔
often when people discuss unsprung weight, they don't know how weight, unsprung weight and inertia of moving parts work, what people often refer to as an unsprung weight of wheel is actually inertia which is = 1/2 * mass * r^2, adding or removing weight from rubber itself would have more impact as it is further away from axis of rotation... even so wheel of 18 and 19 can be of simmilar weight, but 19 one will have soo much leverage on rest of suspension and due to third newtown law it will break some things and it will require more work to get rotated... also regular road tyre compared to semislick is huge difference in weight. Other reason why rotational weight is important is to be able to tune out and design suspension to work around antisquat, antidive and wheelhop thingie as car gets launched, rubber bushings and shocks can only handle so much. This doesen't play a huge role on road other than some feel which can be placeboo just because steering feel can be bit different, but on track events where you brake very late, trail brake into corners, or just brake to shift weight and rotate car and drive on near limit you don't want suspension to do funny things and it's much more manageable to tune setup if wheels are light and suspension has to work less to keep rubber planted since there is less antisquat/antidive to deal with. And yeah 99% of people would be completely fine with oem wheels, but burning money on nice wheels makes people happy so who am i to judge... whatever floats your boat mate :)
@ivanfilipovic3296 so, as usual, "it makes difference on track but on the street no difference", in the end from car mods I did only ones I can recommend is low profile tire, chip tuning if you have turbo car, and maybe bigger brakes so they heatsoak later, that's what matters on the street, unless some mod can give you at least 2-3s of shorter acceleration or ability to start hammering brakes one time after another it's gonna be unnoticeable even in dynamic street driving, as most what you can reasonably flex on others is acceleration let's say 0-70kmh and some fast corners and rapid deceleration, nobody cares about 0.1s either way, what counts is loud exhaust and overtaking the right lane enemy by few car lengths in drag race limited to reasonable speed
@@howabout2138 difference is difference be it on track or road, but there is a point of diminishing returns when going past some point doesen't give much but takes a lot, and it makes more sense to put money elsewhere to make car more fun
@@ivanfilipovic3296 ye but on track every 0.1s makes difference, on the street either you gap someone by 2 car lengths or you don't, thus go big or don't start modding hoping you will gain massive amount of acceleration from driving with empty tank and throwing away spare tire 😀
This was done in 3rd gear, so the time is several seconds which makes the Draggy results nice and consistent. The effect of reducing rotational weight should be much more noticeable in 1st and 2nd. This might be harder to measure. I know that when I replaced my 18lb flywheel with an 8lb one, you could really tell in the lower gears, but it is not noticeable in 3rd-5th.
Great video! I can only feel a small difference in the weight of the wheels on my car going from 195 65 15 for the winter tires and up to 205 55 16 for the summer tires. I feel that i have better handling with the wider summer tires and that the weight of the wheels are perfect even that they are a bit heavier than the original 15" wheels.
The biggest difference would be from 0-100 than 50-110 kmh, it would take a lot more energy to spin it from stationary and would be even more noticeable in less powerful cars.
Awesome tests. That 50-110 test is perfect for a daily and real use measure. Can i suggest a time table on your Google Drive Sheet with all the setups (wheels, weight, intake, exhaust) and times? What's next? Here some ideas: Different tire pressures, before and after oil, filters, plugs change, before and after gearbox oil change, with different octane level fuel, some octane boost additive, before and after injector cleaners, different engine oil levels (close to minimum vs at the max), before and after low friction ceramic oil treatment (LiquiMoly Ceratec or similar), AC on vs off, low vs high alternator load (radio, lights, fans). Keep the great work!
What was the barometric pressure? Outdoor air temperature? Fuel blend? Etc etc... A better test would be comparing two cars side by side then again with the change / swap wheels for example.
It adds absolutely nothing. I work with tire change and wheel balancing and the other day i got some very dirty wheels that needed new tires. What i did when i should balance them was to remove the weights on both the inner and outside of the wheel before i mounted it on the wheel balancer just to see how much the dirt weighed and the result was that the wheel had the same weight both dirty and clean.
I would expect a bigger change in performance between 0-35kmh in 1st gear. Fuel economy and stopping distance would also be adversely affected. These parameters were not measured and the video largely missed the point.
thank you for this test 👍 I like your thinking trying to get to a true assessment comparing extra weight in the trunk to extra rotational mass at the wheel.
A good one. If I find some spare time, I'd like to repeat this experiment. I'd glue some sound deadening material instead of wheel weights. I'd add maybe double the weight of yours. Thanks for sharing.
I suspect you notice it more than the numbers suggest because you don't drive around everywhere full throttle. Part throttle power more noticeably affected by wheel weight I suspect.
Let's appreciate the fact that Tim is speaking a foreign language to make these videos.
Thank you for the continued support Michael🙏
in fact the weight in the wheels affected double of the weight inside the car (a factor of 0,0057 s/kg to 0,096 s/kg). Additionally unsprung weight makes suspension work harder in bumps meaning that a stiffer suspension is needed resting comfort and also driveability.
you create very good content, thanks for it
Okay - so this is a GREAT test as it gives an idea of how the weight of a tyre & rim(wider, thicker, larger)affect acceleration(mileage, handling, etc)... BUT it's 50% unfair, because only 2 wheels got additional weight... All 4 wheels should have received extra weight for the test to be representative of the debate between Rotational Weight vs Static Weight - as even though the front wheels don't drive the car(in your case - GREAT looking car by the way), it still takes(more)energy to rotate them when they are heavier... So the actual times you would get would be worse than the 6,65 etc...🤔
often when people discuss unsprung weight, they don't know how weight, unsprung weight and inertia of moving parts work, what people often refer to as an unsprung weight of wheel is actually inertia which is = 1/2 * mass * r^2, adding or removing weight from rubber itself would have more impact as it is further away from axis of rotation... even so wheel of 18 and 19 can be of simmilar weight, but 19 one will have soo much leverage on rest of suspension and due to third newtown law it will break some things and it will require more work to get rotated... also regular road tyre compared to semislick is huge difference in weight.
Other reason why rotational weight is important is to be able to tune out and design suspension to work around antisquat, antidive and wheelhop thingie as car gets launched, rubber bushings and shocks can only handle so much. This doesen't play a huge role on road other than some feel which can be placeboo just because steering feel can be bit different, but on track events where you brake very late, trail brake into corners, or just brake to shift weight and rotate car and drive on near limit you don't want suspension to do funny things and it's much more manageable to tune setup if wheels are light and suspension has to work less to keep rubber planted since there is less antisquat/antidive to deal with.
And yeah 99% of people would be completely fine with oem wheels, but burning money on nice wheels makes people happy so who am i to judge... whatever floats your boat mate :)
Amazing reply bro
@ivanfilipovic3296 so, as usual, "it makes difference on track but on the street no difference", in the end from car mods I did only ones I can recommend is low profile tire, chip tuning if you have turbo car, and maybe bigger brakes so they heatsoak later, that's what matters on the street, unless some mod can give you at least 2-3s of shorter acceleration or ability to start hammering brakes one time after another it's gonna be unnoticeable even in dynamic street driving, as most what you can reasonably flex on others is acceleration let's say 0-70kmh and some fast corners and rapid deceleration, nobody cares about 0.1s either way, what counts is loud exhaust and overtaking the right lane enemy by few car lengths in drag race limited to reasonable speed
@@howabout2138 difference is difference be it on track or road, but there is a point of diminishing returns when going past some point doesen't give much but takes a lot, and it makes more sense to put money elsewhere to make car more fun
@@ivanfilipovic3296 ye but on track every 0.1s makes difference, on the street either you gap someone by 2 car lengths or you don't, thus go big or don't start modding hoping you will gain massive amount of acceleration from driving with empty tank and throwing away spare tire 😀
@@howabout2138Low profile tires is for looks though, it only makes you slower.
This was done in 3rd gear, so the time is several seconds which makes the Draggy results nice and consistent. The effect of reducing rotational weight should be much more noticeable in 1st and 2nd. This might be harder to measure. I know that when I replaced my 18lb flywheel with an 8lb one, you could really tell in the lower gears, but it is not noticeable in 3rd-5th.
Probably the effect of rotational inertia would be more pronounced at low speed high acceleration scenarios.
I like the videos where you test and collect data to make your conclusions. I can only imagine how much time it takes
This one didnt take too much time tbh but thank you for noticing. Most take quite alot of time yes
the mad man returned xD
I went from 275\65r17 to 195\45r15 alloy wheels on my isuzu. That made a bigger difference than upgrading the turbo.
Great video! I can only feel a small difference in the weight of the wheels on my car going from 195 65 15 for the winter tires and up to 205 55 16 for the summer tires. I feel that i have better handling with the wider summer tires and that the weight of the wheels are perfect even that they are a bit heavier than the original 15" wheels.
I have done similar testing myself and came to the same conclusions.
The biggest difference would be from 0-100 than 50-110 kmh, it would take a lot more energy to spin it from stationary and would be even more noticeable in less powerful cars.
Yes. But also alot harder to get right as there are way too many variables imo
Awesome tests. That 50-110 test is perfect for a daily and real use measure. Can i suggest a time table on your Google Drive Sheet with all the setups (wheels, weight, intake, exhaust) and times?
What's next? Here some ideas: Different tire pressures, before and after oil, filters, plugs change, before and after gearbox oil change, with different octane level fuel, some octane boost additive, before and after injector cleaners, different engine oil levels (close to minimum vs at the max), before and after low friction ceramic oil treatment (LiquiMoly Ceratec or similar), AC on vs off, low vs high alternator load (radio, lights, fans).
Keep the great work!
Great ideas honestly. All of them. Thank you
What was the barometric pressure? Outdoor air temperature? Fuel blend? Etc etc...
A better test would be comparing two cars side by side then again with the change / swap wheels for example.
Pressure i dont know. But temperature was the same, fuel blend too. Full tank both of them
Use an old rubber valve, attach it to a drilling machine and use it to scrub the glue off the rim wihtout damaging the surface.
Thank you. I will give it a try
Ive never wondered this but I have wondered how much weight all that brake dustand dirt adds to a wheel
It adds absolutely nothing. I work with tire change and wheel balancing and the other day i got some very dirty wheels that needed new tires. What i did when i should balance them was to remove the weights on both the inner and outside of the wheel before i mounted it on the wheel balancer just to see how much the dirt weighed and the result was that the wheel had the same weight both dirty and clean.
I have now
I would expect a bigger change in performance between 0-35kmh in 1st gear. Fuel economy and stopping distance would also be adversely affected. These parameters were not measured and the video largely missed the point.
It's gonna make the car faster, duh!! 😂
thank you for this test 👍
I like your thinking trying to get to a true assessment comparing
extra weight in the trunk to extra rotational mass at the wheel.
Thank you for doing this. Interesting comparison.
In the name of science! Hahah sometimes you're a funny guy
so in a track day 1 sec only whit weels haha
Thank you, it was interesting!
Double take at the thumbnail haha
Interesting
A good one. If I find some spare time, I'd like to repeat this experiment. I'd glue some sound deadening material instead of wheel weights. I'd add maybe double the weight of yours.
Thanks for sharing.
Sounds like a cool experiment
I have a couple of wheels with almost that many weights 😅
Lol
I suspect you notice it more than the numbers suggest because you don't drive around everywhere full throttle. Part throttle power more noticeably affected by wheel weight I suspect.
As always, an interesting video, thanks for the upload
That's what I call dedication 👍
Another banger video.
2:31 hadn't noticed that Málaga plate hanging on the wall