lighter wheels tésted

[Petrus]

https://grassrootsmotorsports.com/articles/are-lighter-wheels-really-better/

Although the differences appéar small, they are in fact rather large.
A 0-60 improvement from 9.04 secs. to 8.61 is considerable. And that by simply lighter rims.

Lap times again seem not that much quicker but best lap difference of almost half a second on a sub 1 minute lap time by just lighter wheels is a lót.
It would mean the best lap time difference on the starting grid, followed by 0.3 sec/lap for say 10 laps: By simply mounting lighter wheels 
You would need quite a lot of weight off the car and even more extra horses to get that.

[Beachbum957]

That is a rather extreme comparison

The difference in wheel weights is not small.  The Volk wheels are very light at 3.7 kg (8 lbs) and the Masitally are more than double the weight at about 8.85 kg (19.5 lbs) based on the assembly weight they listed.  That is comparing probably the very lightest wheel you can buy with the very heaviest - over 11 lbs difference per wheel

That should make a performance difference if only because the car is 44 lbs heavier.  Once they ballasted the car to compensate for the weight difference, the 0-60 change was .3 seconds

But the more common wheels are in the 16-18 lb range for that size, so a real world improvement would probably be less.  The real question is what is .2 -.3 seconds 0-60 with to you?   There would be a very large difference in the price of the wheels as well

[Petrus]

The comparison is extreme on purpose to be able to méasure beyond statistical margins.
As to the measured differences: The 0.5 second best lap at say a lowly 70 km/h  means a difference of 10 meters in 1 minute.

Looking at the MR2, the pre FL wheels are 6.6 and 6.8.
A set of wider Enkeis is 4.4 which is about a third lighter.
Add a tyre of say 9 kilos and the diffence becomes relativated 
Still a significant difference in gyroscopic force you wíll notice on quick direction changes.

The differences measured are an indication of better braking, safer cornering in the real world. Greater differences because the road is less smooth there.
Secondly the MR2 has ABS and on the less smooth every day road surfaces this responds very effectively to changes in road contact and lighter wheels equals better road contact.

Look at https://youtu.be/Vx4Gigi8uL8
and you will see that a small % improvement in braking efficiency results in meters of differences.
This is akin differences between high mileage and high grip tyres.

The point is that nó it does not change the car and perfórmance wise the effect is only twice the weight off the car.
The better road contact is also low single digit %. 
Still not bad to stop 1 , 2 meters shorter from 50 km/h and change direction quicker.

Remember; the test is ónly a change of lighter wheels. Even if you half the difference, half the effect, it still is rather a difference from júst a set of rims.

[tom256]

And what about lightweight brake discs? Any recommendation to MR2?

[shnazzle]

And what about lightweight brake discs? Any recommendation to MR2?

Never knew there was such a thing until you get into the realms of the proper proper because race car innit stuff made from all sorts of jazzy materials we couldn't afford

Wilwood make front calipers that reduce the unsprung weight a fair bit.

[tom256]

And what about lightweight brake discs? Any recommendation to MR2?

Never knew there was such a thing until you get into the realms of the proper proper because race car innit stuff made from all sorts of jazzy materials we couldn't afford

Wilwood make front calipers that reduce the unsprung weight a fair bit.

Actually there are ceramic-carbon, but these are crazy expensive.
I was thinking about alloys break disc, lighter than stock and with reasonable price.

Here I found something:

https://www.eliseparts.com/products/show/21/909/s2-lightweight-brake-discs/

but I'm new to this topic, and these are still expensive.

[shnazzle]

Well who knew!
Every day is a school day. And yes they are expensive but for track guys, it might be just what gives the edge

[Petrus]

Billet alumium Wilwood saves unsprung weight BUT need 16" rims which.... negates the weight gained.
They do give improved modulation.

A replacement lightweight semi floating disc is not availeble. That would ave some weight at no penalty.

As to the braking capacity the originals do not even need replacement hard lines. I did replace them and noticed that the slight ´give´ is in the abs system.

The Spirit MR-S races with the original set up without the ABS and a balance valve fitted to give some more rear bias.

For road purposes the braking system needs no upgrades and as I observed, the lighter calipers need heavier wheels, so...

[shnazzle]

Once again proving the Law of Carolyn; leave the damn thing stock

[Petrus]

Once again proving the Law of Carolyn; leave the damn thing stock

Do see her  :notworthy:  in the light of the average user and normal circumstances.
Take the example of ´better´ tyres; it is ever so easy to step in the trap of too good (race wubbah) being way bad (for the road). And tyre ´specialists´ are not (specialist experts), bar exceptions.
It is indeed a golden rule that the factory set up is an optimum which is basically impossible to improve upon.

Lighter rims in standard diameter are a ´no cost´ win. The factory optimum needs to incluse the monetary value of the rims.

Same thing Dev´s door spacers with the caveat about what to expect 
It is NOT a fool proof consumer thing. See the costly TRD thing; again the cost aspect.

Her head steady mounting kit is already pushing the fool proof user envelop with the OEM engine mounts as an additional trap.

[1979scotte]

Once again proving the Law of Carolyn; leave the damn thing stock

But wouldn't it make life dull?

[Petrus]

But wouldn't it make life dull?

There is always vinyl!!!

[Petrus]

Had an interesting experiences exchange with a Smart Coupé Brabus owner.
In winter he puts his car on the base model steel rims with ´narrow´ high section rubbers.
It has better steering response, better road contact and weigh (bb) less inertia. He observed they are noticeably quicker off the line.
He did not realise they stop even more better; better compliance = better contact ánd they have less inertia.
´WOW!!!´ he daid when that penny dropped.
He will still put the 17" alloys with summah wubbah on  (:< >
Ah well, he also thinks a coupé with an electric targe sunroof is a cabrio