Is 12lb total difference in weight going to affect a lot?

[why?]

Originally Posted by khcho19

So I am looking at some wheel that weights 20 lbs. This is my option 1.

My option 2 has 23 lbs, so total difference for a set of 4 would be 12 lbs.

Will 12 lbs make a difference a lot?

What's ideal wheel weight for BRZ?

What do you use the car for? If it is a DD that probably should not make a difference. If it is or any sort of performance though there is a chance you might be able to feel the difference. There are plenty of people who have bought wheels and tires for just style and hated how the car drove afterword. Also remember bigger tires cost a ton more and weigh a ton more as well.

Originally Posted by mrg666

Don't help with what? Speed, grip, mpg? How about writing a coherent sentence first? I think everybody knows that wider tires are heavier, reduce top speed, and have more drag. But sports/race cars generally have wider tires than other cars. I wonder why? Even the car manufacturers are missing it, right? How many more times will you repeat this broken record?

car manufacturers are missing it. But they are totally ruled by stylists and massive discounts from tire manufacturers that want to make tons of money on these gigantic tires.

[StraightOuttaCanadaEh]

The only difference I've noticed is the jolting due to increased weight. I release the throttle and feel a jolt, same with getting back on the throttle. It's like the engine is struggling through that momentary hesitation that heavier wheels result in. Or maybe it's cause the tires are grippier. Who knows. I'm just guessing

[mrg666]

Originally Posted by why?

car manufacturers are missing it. But they are totally ruled by stylists and massive discounts from tire manufacturers that want to make tons of money on these gigantic tires.

I would have preferred if I had 225 performance tires with forged (i.e. lighter) 7.5" or 8" rims when I bought it. It made a big improvement in handling when I upgraded. I wouldn't have installed 245 tires without supercharger though. Those are too much drag for NA power. See, I don't claim wider is always better. But it seems you claim narrower is always better which is wrong in my opinion. Sure, go ahead and do what you want with your car. I won't be running after you to say you are doing wrong. As long as you and I are safe and happy, what is the point of argument?

[why?]

Originally Posted by mrg666

I would have preferred if I had 225 performance tires with forged (i.e. lighter) 7.5" or 8" rims when I bought it. It made a big improvement in handling when I upgraded. I wouldn't have installed 245 tires without supercharger though. Those are too much drag for NA power. See, I don't claim wider is always better. But it seems you claim narrower is always better which is wrong in my opinion. Sure, go ahead and do what you want with your car. I won't be running after you to say you are doing wrong. As long as you and I are safe and happy, what is the point of argument?

not really with this car. The new Avalon has 19" wheels. There is zero reasons for that besides kickbacks from tire companies. Same thing with all these crossovers have 19 and 20" wheels. Totally useless and absurd. My parents bought a Nissan Murano and when they had to replace the tires they had to drive 3 hours because literally no one had that size, even the dealer didn't want to order it. And the price was totally insane. Gigantic wheels are tires are one of the hidden costs that are driving the price of cars through the roof.

Honestly the twins come with the right size wheels and tires. 215/45/ 17 has been a hugely popular size tire for decades, my old Saab Viggen had that size. I just wish instead of the useless oversize brakes they used the WRX 4 pots so that all the usual wheels could fit. Still 50/50 on switching and buying some crazy lightweight 15". Remember the wheels on my Yaris weigh 6.5 lbs. That totally changed the character of the car.

[Leonardo]

Originally Posted by why?

There is zero reasons for that besides kickbacks from tire companies.

IDK about Zero. Maybe people have been trained for the last 20 years or more (Cab Calloway sang about his car with "big platinum wheels" in 1931) to think bigger wheels are cool by music and movies. And that they help sell cars.

[mrg666]

I'll agree with you there. Some cars do come with unnecessarily large wheels. Then they go complain about how bad are the roads after hitting a pothole.

Originally Posted by why?

not really with this car. The new Avalon has 19" wheels. There is zero reasons for that besides kickbacks from tire companies. Same thing with all these crossovers have 19 and 20" wheels. Totally useless and absurd. My parents bought a Nissan Murano and when they had to replace the tires they had to drive 3 hours because literally no one had that size, even the dealer didn't want to order it. And the price was totally insane. Gigantic wheels are tires are one of the hidden costs that are driving the price of cars through the roof.

Honestly the twins come with the right size wheels and tires. 215/45/ 17 has been a hugely popular size tire for decades, my old Saab Viggen had that size. I just wish instead of the useless oversize brakes they used the WRX 4 pots so that all the usual wheels could fit. Still 50/50 on switching and buying some crazy lightweight 15". Remember the wheels on my Yaris weigh 6.5 lbs. That totally changed the character of the car.

[rvoll]

Originally Posted by mrg666

I would have preferred if I had 225 performance tires with forged (i.e. lighter) 7.5" or 8" rims when I bought it. It made a big improvement in handling when I upgraded. I wouldn't have installed 245 tires without supercharger though. Those are too much drag for NA power. See, I don't claim wider is always better. But it seems you claim narrower is always better which is wrong in my opinion. Sure, go ahead and do what you want with your car. I won't be running after you to say you are doing wrong. As long as you and I are safe and happy, what is the point of argument?

Exactly.... Couldn't agree more.... Except, I see so many posts trying to justify wider in terms of performance. That said, I especially agree with your point about being safe and happy. As long as you are not harming me, do anything you want with your car with the possible exception of pollution items. I don't even care about loud cars. I'm especially sensitive about pollution items because of a family member with emphysema who was especially sensitive to smog. So when people remove their cats, I am annoyed.

[mrg666]

Originally Posted by rvoll

Exactly.... Couldn't agree more.... Except, I see so many posts trying to justify wider in terms of performance. That said, I especially agree with your point about being safe and happy. As long as you are not harming me, do anything you want with your car with the possible exception of pollution items. I don't even care about loud cars. I'm especially sensitive about pollution items because of a family member with emphysema who was especially sensitive to smog. So when people remove their cats, I am annoyed.

I'm also sensitive to pollution and efficiency. Twins are very efficient when driven normally even with supercharger. I'm glad we found some common ground

[mrg666]

Originally Posted by Leonardo

IDK about Zero. Maybe people have been trained for the last 20 years or more (Cab Calloway sang about his car with "big platinum wheels" in 1931) to think bigger wheels are cool by music and movies. And that they help sell cars.

True, people like big wheels. I personally prefer a balance between form and function. I wanted to buy this car because of the balance i was able to see between form and function in its design.

[rvoll]

Originally Posted by mrg666

I'm also sensitive to pollution and efficiency. Twins are very efficient when driven normally even with supercharger. I'm glad we found some common ground

Yeah, we agree more than it is apparent. I read all of these posts about people who want to know whether this wide wheel fits or that wide wheel fits. It seems that many of these posts come from people who really have little knowledge about car performance and they seem to get encouragement from others without one word about whether it will be better from a performance perspective. It's one of my pet peeves from the internet -- people think everything they read, and want to believe, is true.

And yes, the twin is about the best balanced car on the market today -- and one of the most fun. In my mind, doing a lot of mods on this car -- unless it is raced -- makes me cringe. That said, I understand the sex appeal of modding a car like this with all of the Christmas goodies that are available. It's really hard, emotionally, to not mod this car. I still look through all of the modding posts and goodies from dedicated sources with the amazement of a child. I tried to justify getting new wheels, but at the end of the day, couldn't justify it on the basis of performance. I tried to justify lowering the car because it certainly looks better that way, but for a street car, it does not improve performance -- and in fact, reduces ride quality. I looked at getting a turbo and tried to justify that. However, I read the statement by the car's designer that adding hp would require a significant change in the car's structure to achieve a good balance. I did, however, buy better tires because of what virtually everybody here said about the Primacy HP's and the track tests run by Tirerack. At least there, I found some performance reasoning. Oh, well....

[Yardjass]

Originally Posted by rvoll

From a nationally rated car magazine or testing organization and not two high school physics teachers? Bring it on..... You should also look at the tests done with Tirerack where they put on ultra high performance 215's on an 86 and said it was too much traction. But that test was done by a nationally known race driver. What would he know?????

Honestly, I probably would trust the physics teachers. At least they have a STEM background, unlike most of these journalists.

Originally Posted by rvoll

It seems that many of these posts come from people who really have little knowledge about car performance and they seem to get encouragement from others without one word about whether it will be better from a performance perspective.

Yep.





On a more serious note, none of these so-called tests are at all useful. Race car drivers rarely agree with their engineers, often opting for technically inferior setups that "feel better" to them and therefore produce better laps. What works on a power circuit might not be as fast on a course with more turns or even an autocross setup. Skidpad numbers are an ineffective way to measure all aspects of handling. There are way too many variables to prescribe the best setup to everyone for their street car. Inferior setups that "feel" better to one person could end up being faster for them. It could be the other way around for someone else. Unless you're going to hook them up to some expensive equipment at one of the tire manufacturers and run them through their paces or throw the setups on an autonomous vehicle one after the other and tell it to run laps in similar weather conditions, there is way too much human error and other variability involved. Not to mention, even if you did, go back to what I said earlier about how results would vary based on the type of course being run. About all we can definitively say is:





Wider tires within reason mean better grip to launch but slower top end due to drag and slower acceleration/braking due to a greater rotational moment of inertia. However, you do get better handling.





A better tire compound is more important than anything mentioned above.





The heavier wheel/tire package is not always wider.





Heavier means a worse ride quality.








I do get quite a kick out of “slow car fast” people complaining about changes in wheel/tire setup that will have a nearly negligible effect on their car’s performance though.

[ermax]

Originally Posted by rvoll

From a nationally rated car magazine or testing organization and not two high school physics teachers? Bring it on..... You should also look at the tests done with Tirerack where they put on ultra high performance 215's on an 86 and said it was too much traction. But that test was done by a nationally known race driver. What would he know?????

Too much traction for what? Lap Times or fun factor. Those are two very different things. Never in my life have I heard someone say more traction will hurt lap times (assuming we are talking about the same mass). Fun factor, well yeah that makes sense. Sliding around turning slow laps is always fun.

Edit: Just to clarify, I am also assuming same dimensions. You said 215. By that I assume the test was done on the OEM rims but with ultra high perf tires. No way would that make a slower car. Do you have a link to this article?

[rvoll]

Originally Posted by Yardjass

Honestly, I probably would trust the physics teachers. At least they have a STEM background, unlike most of these journalists.







Yep.





On a more serious note, none of these so-called tests are at all useful. Race car drivers rarely agree with their engineers, often opting for technically inferior setups that "feel better" to them and therefore produce better laps. What works on a power circuit might not be as fast on a course with more turns or even an autocross setup. Skidpad numbers are an ineffective way to measure all aspects of handling. There are way too many variables to prescribe the best setup to everyone for their street car. Inferior setups that "feel" better to one person could end up being faster for them. It could be the other way around for someone else. Unless you're going to hook them up to some expensive equipment at one of the tire manufacturers and run them through their paces or throw the setups on an autonomous vehicle one after the other and tell it to run laps in similar weather conditions, there is way too much human error and other variability involved. Not to mention, even if you did, go back to what I said earlier about how results would vary based on the type of course being run. About all we can definitively say is:





Wider tires within reason mean better grip to launch but slower top end due to drag and slower acceleration/braking due to a greater rotational moment of inertia. However, you do get better handling.





A better tire compound is more important than anything mentioned above.





The heavier wheel/tire package is not always wider.





Heavier means a worse ride quality.








I do get quite a kick out of “slow car fast” people complaining about changes in wheel/tire setup that will have a nearly negligible effect on their car’s performance though.

Mostly agree with what you've said. However, I do have a STEM background and real world testing is part of scientific proof. Doing one without the other is not worth much. So I really can't support the two high school physics teachers as the equation is much more complex than they've propounded. Getting a car setup properly is highly complex, as you have noted.

And yes, as I've said before, there is a psychological aspect (how your car feels) to performance for individuals. But that is why we look for objective testing.

The one point where we disagree, however, is that wider tires improve handling as a general principle. Handling, IMO, is a matter of balance. Our car is designed for 215's on the front and in my experience, the accuracy of handling degrades as you go wider on the fronts. That said, there are specific circumstances, like autocross, where a slightly wider tire may give better times. But that is the exception as not very many owners do autocross.

Lastly, where we agree violently, is that tire compounds make much more of a difference than most of this other junk. Putting 225/45R17 PS4S's on my car changes how the car "sticks" to the road dramatically over the OEM Primacies. Testing at Tirerack shows that it also reduces lap times (although they upgraded with Pole Position tires). I don't think wider tires could possibly stick more as these stick almost too much. That is, there is a sweet spot where going wider doesn't help anymore.

[rvoll]

Originally Posted by ermax

Too much traction for what? Lap Times or fun factor. Those are two very different things. Never in my life have I heard someone say more traction will hurt lap times (assuming we are talking about the same mass). Fun factor, well yeah that makes sense. Sliding around turning slow laps is always fun.

I agree. I didn't say that more traction would hurt lap times (although I can see where that would be inferred). Only that there comes a point where traction is maximized for the specific car and getting tires with theoretically more grip doesn't really help -- and in fact, because of things like weight and the shape of the contact patch and drag, may worsen lap times.

And yeah, if you really like sliding, keep the OEM Primacies as they do that well on this car. And yes, sliding can be loads of fun if that is your objective. I personally get more fun when the car sticks -- but that is me....