Do lightweight wheels make the car faster?

[TommyW]

Originally Posted by JT.86

if you're worried about that 5 lbs, just go on a diet. :/

Doesn't work like that......

[Vracer111]

Originally Posted by TommyW

205?

Yes, a 205/45 profile is ideal for a 7.5" wide wheel, the tread width is a little wider than the stock 215/45 Primacy HP's. Tire compound is what gives you grip, tire width does virtually nothing for grip. Tire width will make the car more stable/resistant to changing direction... which is a way of saying it reduces the agility you can have from a narrower tire.

IMO, a 205/45-17 Max Performance tire is the optimal fitment for the FR-S if you value agility and responsiveness. You get a gearing advantage from the smaller diameter - so it responds really well to throttle input, you get a lower CG by nearly .2", it is the lightest 17 tire size, the tread width is the same to slightly wider than stock, and the car feels so nimble and light on its feet while at the very same time absolutely planted and stable at high speeds. Going with larger tires just drags the chassis/suspension down, working against enhancing its agility.

What 205/45-17 tires on a 17x7.5 +40mm wheel looks like:

Example 1 (Ecsta Sport LE)




Example 2 (ExtremeContact DW)

[why?]

Originally Posted by TommyW

Here's a question for you as I'm on the fence between 245 40 17 and 225 45 17. The 245's are a lb lighter so do you feel that with the added rolling resistance but lighter weight it would be a wash on straight line performance? I'd imagine overall the 245's would be better when you consider cornering in the equation of overall performance? Thoughts?

what are you trying to do? Are you racing nationally and that width could mean the difference between having enough grip and losing?

Or are you just try to enjoy the car? Tire composition is going to make a hell of a lot more difference than tire size until you are going for that last final tenth of a second or two in competition.

Like Vracer111 mentioned, the smaller the tire size the better for outright agility and fun to driveability of our vehicles. Unless you need to clear brakes or are going to compete and are going to eventually need to upgrade to bbk's, those gigantic tires are only good for cars with a hell of a lot more power or people that are competing at extremely high levels.

And to be totally honest, unless you can find wheels and tires that are significantly lighter, which just don't seem to actually exist, then there is no reason to stray from what you have.

I remember in my Yaris going from wheels & tires that were over 45 lbs a corner to 25 or so lbs a corner. That made a gigantic difference. But nothing like that exists for the 86. The lightest wheels you can buy are 10.5 lbs and 16x 7, and the lightest wheels are 16 lbs and 205/55/16. That is 26.5 lbs per corner, while the combo you first mentioned is 43.5 lbs per corner. To me 5 lbs a corner isn't worth the expense. And spending $2600 + on a set of wheels is crazy. I did it once, I just don't know if I want to do it again.

[Yardjass]

^^^ Yep. I'll be getting wheels because I want something that looks nicer than the stock ones. They'll probably be around 5 lbs a corner lighter than stock but I don't expect to notice a whole lot of change. When I added almost exactly 5 lbs a corner according to a postage scale to my (slow) NA Z, I hardly noticed any change in speed at all. Didn't notice a whole lot in ride quality either because it was already horrible, having coilovers with track spring rates on it.

Originally Posted by TommyW

right, thanks. Want to go 8" so I can use a 225 or 245.

You could get away with either but I recommend 225 based on a lot of feedback from places like 949 racing and miatter owners. I definitely wouldn't stray outside of that range. Also, keep in mind the brand of tire you are buying. For example, hankook 245's are more like 255's so I'd go with one of their 225's.

[TommyW]

Originally Posted by Yardjass

^^^ Yep. I'll be getting wheels because I want something that looks nicer than the stock ones. They'll probably be around 5 lbs a corner lighter than stock but I don't expect to notice a whole lot of change. When I added almost exactly 5 lbs a corner according to a postage scale to my (slow) NA Z, I hardly noticed any change in speed at all. Didn't notice a whole lot in ride quality either because it was already horrible, having coilovers with track spring rates on it.





You could get away with either but I recommend 225 based on a lot of feedback from places like 949 racing and miatter owners. I definitely wouldn't stray outside of that range. Also, keep in mind the brand of tire you are buying. For example, hankook 245's are more like 255's so I'd go with one of their 225's.

Yes correct. Im getting Bridgestone Potenzas and they're narrow for a 245. Yes when people speak of sizes they need to understand that widths vary widely even though the sizes are listed are the same.

With the Enkei TS 9's and the Bridgestones at 23 lbs the weight is very close to stock and the diameter is virtually the same.

[Icecreamtruk]

Its funny how a lot of people recommend sizes and what not, but reading the comments its easy to spot who understands how tires generate grip and the actual difference between wider/thinner tires.

[nikitopo]

Try to drive your car with a full fuel tank and with an (almost) empty tank. Can you feel any difference? Some drivers cannot notice anything, while others can. So it depends also on your senses. In general you won't gain anything if you remove 2lbs or 5lbs. It is the total weight gain that counts.

[Tcoat]

Originally Posted by nikitopo

Try to drive your car with a full fuel tank and with an (almost) empty tank. Can you feel any difference? Some drivers cannot notice anything, while others can. So it depends also on your senses. In general you won't gain anything if you remove 2lbs or 5lbs. It is the total weight gain that counts.

I frequently wonder how people think they can feel a difference with a few pounds added or removed. It frequently is well under 5% of the car's weight yet they swear they get a 20% improvement in all performance. Placebo effect and confirmation bias are strong influences on the human brain.


Now, start to remove 100s of pounds and it is a whole different ball game.

[TommyW]

Originally Posted by nikitopo

Try to drive your car with a full fuel tank and with an (almost) empty tank. Can you feel any difference? Some drivers cannot notice anything, while others can. So it depends also on your senses. In general you won't gain anything if you remove 2lbs or 5lbs. It is the total weight gain that counts.

Fuel is sprung weight and wheels, tires are not

[StraightOuttaCanadaEh]

^

I was gonna say, unsprung weight is a bit different. That's just rotational inertia, centrifugal forces etc. At speed those 5 lb turn into hell of a lot more

EDIT: To be specific, what it hurts is acceleration.

[Impureclient]

Originally Posted by nikitopo

Try to drive your car with a full fuel tank and with an (almost) empty tank. Can you feel any difference? Some drivers cannot notice anything, while others can. So it depends also on your senses. In general you won't gain anything if you remove 2lbs or 5lbs. It is the total weight gain that counts.

I feel the car sliding more when it's time to fill up. That's only 10 gallons down, so 62 lbs. With 5 lbs at each corner, 20 lbs total unsprung and supposedly equivalent to 200 lbs sprung, it seems like that would be noticeable.
Either way, after reading all these comments, I think I'll not pay to get lighter wheels and instead stick with what I got since it may or may not even make a difference other than feel.

Now it's either stay with the Michelin PSS when it's time for new tires or try these Firestone Firehawk Indy 500 that are getting a lot of rave reviews. They appear to be like 95% of the
performance of the MPSS for 70% of the price.

[reeves]

Originally Posted by Impureclient

Now it's either stay with the Michelin PSS when it's time for new tires or try these Firestone Firehawk Indy 500 that are getting a lot of rave reviews. They appear to be like 95% of the
performance of the MPSS for 70% of the price.

Let us know how those tires work out. I'm still hesitant to put anything branded Firestone on my car after their nationwide fiasco several years back.. whether it's a performance summer tire or all-season economy tire.

[smg1138]

Originally Posted by reeves

Let us know how those tires work out. I'm still hesitant to put anything branded Firestone on my car after their nationwide fiasco several years back.. whether it's a performance summer tire or all-season economy tire.

What nationwide fiasco are you talking about? I must have missed that. I was actually considering the Indy 500's for my next set of street tires.

[Impureclient]

Originally Posted by smg1138

What nationwide fiasco are you talking about? I must have missed that. I was actually considering the Indy 500's for my next set of street tires.

In 2000, there was a recall for SUV tires they made for Ford Explorers.

As far as those new Indy 500s, there isn't a negative review online and I've been reading through everything I could find online.
Either people like them or love them who have used them. Pretty sure that's what I'm trying next.