It doesn't look like I can loose any weight with the tires (I'm not buying new wheels). From my research on TireRack the lightest tires in my size and category are the OE tires I have. Everything else weighs more.
Would an additional 4 lbs. per tire be noticeable? (tire weight, not air)
- Thread starter wbwanzer
- Start date
Instead of trying the tire that I was hoping to try, I'll pick either the tire that's 1 lb. more or the other one at 2 lbs. more.
I think us BITOGers are in a different world than the average Joe. Average Joe goes out to buy tires not knowing or caring what his current tires weigh and not knowing what the new tires will weigh. And life will go on without making a project out selecting new ties. Some times I wish I didn't obsess over this stuff like I do.
I think us BITOGers are in a different world than the average Joe. Average Joe goes out to buy tires not knowing or caring what his current tires weigh and not knowing what the new tires will weigh. And life will go on without making a project out selecting new ties. Some times I wish I didn't obsess over this stuff like I do.
Don't forget the impact of unsprung weight on suspension performance. It's not just the inertia of rolling mass, but also the turning and damping.
The question on if you'll notice all depends on your perception as a driver. Some will notice, some will not.
The question on if you'll notice all depends on your perception as a driver. Some will notice, some will not.
Who's obsessing?
You thought of something and asked about it on a suitable forum way fewer than 24 hours ago.
You're not stymied as you are at least passingly familiar with terms like "unsprung weight" and "inertia".
Just go on and beat the next dragon.
Post #16. F1eng was an F1 engineer and sort of disputes what you are saying. I’m not taking sides just something for consideration.
“The difference between Iron and composite brakes on a F1 car is just weight, not unsprung (that made no difference) but just weight, the lap time gain is entirely just the weight saving, 10kg lighter is around 0.35 secs per lap quicker wherever the weight comes from and composite brakes are well worth it for that. The reduction in rotational inertia is very small, Inertia is totally dominated by the tyre.”
https://www.taycanforum.com/forum/threads/porsche-active-ride.18992/
There's a 5 lb difference (39 vs 44 lbs) between the summer and winter sets on our P2 V70 and it is noticeable on that vehicle. The heavier wheels take more effort to accelerate, brake and the suspension does not feel as responsive. You also get used to it and forget about it overtime. I'm not sure if it would be as noticeable on a vehicle with more power and better brakes.
With that said, I wouldn't base a tire decision on weight alone.
With that said, I wouldn't base a tire decision on weight alone.
edyvw
$50 site donor 2025
Absolutely noticeable! I have in winter lighter wheel +tire combo due to smaller sizes on all 3 vehicles and mpg increases while acceleration is noticeable better, especially on Atlas.With a heavier tire your car has greater momentum while moving so in theory you can coast farther thus saving gas
IMHO, in real life you will not notice the difference in acceleration, braking and gas mileage.
The thing is, I didn't just start thinking about this 24 hours ago. I've been fooling around with this tire research for months now. I just decided to get BITOG involved yesterday. Also, I don't do this eight hours a day, everyday. I get hung up on it a bit and then let it go for a while. I don't need the tires right now.
And thanks to everyone who has responded.
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I won't. All tires that I'm considering are name brand with good reviews.
Unsprung weight is roughly the effect of four times sprung weight. So 4 lbs per corner multiplied by four corners = 16 lbs, multiplied by four again is roughly the equivalent of carrying around 64 lbs of dead weight at all times.
Thanks for that information.
The last half sentence is applicable to OP’s question “…inertia is totally dominated by the tyre.”
That said, though unsprung weight may not matter to F1 lap times as much as total mass matters, I respectfully submit that F1 lap time is not the entire model in play here.
Consider the following: On the street, we’re not trying to save 0.35s off of our commute, we’re trying to keep the tires on the road and the ride no harsher than needed. For street cars and their much larger wheel travel than F1, less unsprung weight will make a significant difference to keeping tires on the ground in the real world where roads are not F1 track smooth, and allow the ride to be smoother.
I always look at the weight of tires before buying. I put all terrain tires on my ‘16 Sante Fe after the factory tires were worn out. They are 3-4lbs heavier than the stock that came on it. I bought the falken wildpeak at3w because it was lighter than a lot of other choices in an AT tire. My Sante Fe already has a severely underpowered 2.4L engine. I feel like I’m pulling a trailer with that thing. Horrible acceleration. Then weight it down with the family and luggage plus the dog and it’s a tank. Heavy tires are not needed. I passed on the falken wildpeak AT trail because it was a full 10lbs heavier than the stock tire. Nope. The at3w is like 32lbs I think in my size. Stock tires on my Sante fe were 28 if I remember correctly. The new falken wildpeak At4w is 39lbs in my size. Holy crap! I’ll stay away from those. Even with what I have now with the at3w I definitely took a gas mileage hit. Not a huge deal though. I don’t track my mileage but feels like I get gas way more often now. Plus acceleration is a tad slower too. Could be in my head. Lol.
The problem when trying to figure out what effect weight is going to have on tire performance is that there are many things that also affect tire performance - and some of them have a larger effect than weight.
Tread rubber has about the same density regardless of the formulation, but the range of traction, treadwear, and rolling resistance is HUGE!!! This particularly affects perceptions of performance compared to OE tires. OE tires have the lowest RR, so the affect an aftermarket tire has is going to be profound on acceleration.
The word of warning I want to impart is to be very careful comparing OE tires with anything else.
Tread rubber has about the same density regardless of the formulation, but the range of traction, treadwear, and rolling resistance is HUGE!!! This particularly affects perceptions of performance compared to OE tires. OE tires have the lowest RR, so the affect an aftermarket tire has is going to be profound on acceleration.
The word of warning I want to impart is to be very careful comparing OE tires with anything else.
Which tires are you coming from and going to? In the same size, 4lbs difference seems like a lot? If you are coming from the OEM mileage focused tires and going to an all-terrain type tire, it might feel a tiny bit sluggish compared to nearly worn out OEM tires with less than half the tread, and more sidewall plys may transmit more noise into the suspension?
On the the Outback, I think the new snow tires on steel rims is about 3-4lbs per wheel heavier than the worn out OEM all-seasons on the same rims, and I didn't notice anything, other than the new tires are quieter on the highway... Ride and small bump handling was close enough that I didn't notice at all. Acceleration is close enough in normal driving at least.
All things equal, a lighter tire and rim is better, but in the realm of DDer's a 4lbs isn't going to do anything drastic.
On the the Outback, I think the new snow tires on steel rims is about 3-4lbs per wheel heavier than the worn out OEM all-seasons on the same rims, and I didn't notice anything, other than the new tires are quieter on the highway... Ride and small bump handling was close enough that I didn't notice at all. Acceleration is close enough in normal driving at least.
All things equal, a lighter tire and rim is better, but in the realm of DDer's a 4lbs isn't going to do anything drastic.
Insight. If it Ain't Broke: Don't "fix" it. You don't need no new wheels and heavy tires. Replace the oem size tires on your existing wheels and have a merrier Christmas. .02
Good call. Just funnin' ya.
