Konig feather weights? Update - installed!

[Insomniator]

Hmmmm now I'm thinking about motegi sp10's

http://www.carid.com/motegi-racing-wheels/sp10-black-860230.html

Its impossible to choose a wheel, its not like you can test them out on your car. I just know I don't want black. Silver or gunmetal, or maybe hyper black like these.

 

[ballmode]

Are the Enkei RPF1's light?

 

[JulesMaximus]

Its just one of those things... itching to upgrade something and feel like ~$600 is burning a hole in my pocket for it.

My current wheels are rashed pretty bad and a catback exhaust would not bring much performance to the table, header too much $$$, cam would cost a good amount of money to buy and have installed, a tune would be pointless without further upgrades. If new wheels give the car a much better look and a little bit more performance I can't think of a better way to slake my craving!

There are always motorcycles. :biggrin::ninja:

I kind of dig those wheels actually.

 

[iamwiz82]

I'm thinking now maybe it makes more sense to buy a used set of better wheels? These konigs are pretty much the cheapest you can buy aftermarket... but I see used wheels for sale all the time... its not like they go 'bad'

Would it be smarter to spend 600-900 on a used set of wheels that were originally 300 - 400 each?

A smaller supercharger pulley will net you power quickly. In my old R53 I drilled out the intake box to the firewall area. No performance gain but I loved the sound of the supercharger.

 

[T2urtle]

Disagree, that's like saying you wouldn't notice a difference if a brick was tied to each of your feet.

Going from 25lb stock 17" to 18lb 18" was a huge difference for me both on the street and the track. I wish I had gone with a lightweight 17" instead to get another ~2lb off per corner. If 2-piece rotors weren't so expensive I'd have those as well to shave another 7lb off each front wheel.

i dunno about it, to me it didn't feel much different. I went from stock 25lb 17inch wheels to Forged 18.5lb 18inch wheels. Felt almost the same. I think the tire weights might even it out a little bit.

I ran faster with the 17s at the 1/4 mile, but that was only one pass on someone's stock wheels with all-seasons VS my summer rubber (Kumho LE sports)

 

[JCH13]

Hmmmm now I'm thinking about motegi sp10's

http://www.carid.com/motegi-racing-wheels/sp10-black-860230.html

Its impossible to choose a wheel, its not like you can test them out on your car. I just know I don't want black. Silver or gunmetal, or maybe hyper black like these.

Dark wheels = :|

Do silver.

Are the Enkei RPF1's light?

Exceptionally light.

 

[exar333]

Dark wheels = :|

Do silver.



Exceptionally light.

Dark wheels can look great, especially on black/gray cars and even some bright colors too.

OP - those wheels look great. You will likely notice the difference.

 

[JCH13]

Dark wheels can look great, especially on black/gray cars and even some bright colors too.

OP - those wheels look great. You will likely notice the difference.

They can, but generally they don't. Just like a black car: they look great when they are perfectly clean, but look pretty bad as soon as they're a little dirty.

Besides, the wheels have a really great pattern on them, one that should be highlighted on the car, not hidden by black or dark coloring IMO.

 

[Imported]

Are the Enkei RPF1's light?

Yes. Very much so.

 

[Insomniator]

Thanks everyone, got the Konigs in silver. They were the first to catch my eye, and also happened to be the cheapest and lightest. At 125 a pop I can replace em pretty easily if needed

 

[disappoint]

If you have a 1/2 tank as opposed to a full tank, do you notice a performance increase? How about full tank vs. almost empty?

1 US gallon of fuel weighs about 6 pounds. So if you don't notice the difference of a 1/2 a tank of fuel you might not notice the lower wheel weight.

But every little bit counts, and if you really like the look of the wheels I say go for it. It won't hurt performance even if it doesn't gain all that much.

 

[JCH13]

If you have a 1/2 tank as opposed to a full tank, do you notice a performance increase? How about full tank vs. almost empty?

1 US gallon of fuel weighs about 6 pounds. So if you don't notice the difference of a 1/2 a tank of fuel you might not notice the lower wheel weight.

But every little bit counts, and if you really like the look of the wheels I say go for it. It won't hurt performance even if it doesn't gain all that much.

Heavier wheels are more than just static mass, thus your fuel tank analogy is faulty.

Wheels are rotating, so they not only posses linear kinetic energy as if they were static but also rotational energy. Thus more power is required to get their mass up-to-speed, or stopped.

The gyroscopic effect of heavier front wheels will make steering feel heavier and the driver will have less feedback.

Lighter wheels/tires increases the response frequency of each suspension corner, allowing the suspension to react to changes more quickly which will improve traction and handling characteristics.

I find that all of these characteristics are noticeable when a reasonable portion of unsprung/rotating mass is reduced. Specifically I notice these effects when I change from 16in winter wheels/tires to 18in summer wheels/tires.

 

[Apex]

Heavier wheels are more than just static mass, thus your fuel tank analogy is faulty.

Wheels are rotating, so they not only posses linear kinetic energy as if they were static but also rotational energy. Thus more power is required to get their mass up-to-speed, or stopped.

Exactly. A 1 to 1 comparison is simply way off base.

It's even more the case with your flywheel. Losing 10 lbs off your flywheel can easily be felt, even more than wheels.

 

[disappoint]

Yes but a full tank of fuel weighs more than the difference in weight of his new wheels vs. stock.

 

[JCH13]

Yes but a full tank of fuel weighs more than the difference in weight of his new wheels vs. stock.

You are missing the point entirely, intentionally it seems. Re-read the last couple posts.

 

[cbrsurfr]

Yes but a full tank of fuel weighs more than the difference in weight of his new wheels vs. stock.

You are not comprehending sprung vs. unsprung weight. Yes if you are comparing lbs to lbs and ignoring everything else, 40lbs of fuel is greater than 32lbs of wheels. But since the wheels are unsprung they have a greater affect than fuel which is sprung weight. The formula itself is complicated and depends on many factors but generally unsprung is 2-5 times the difference of sprung. So that 32lbs in wheels can feel like anywhere from 64-160lbs difference in sprung weight.

 

[brainhulk]

Yes but a full tank of fuel weighs more than the difference in weight of his new wheels vs. stock.

son i am dissapoint

 

[brainhulk]

Are the Enkei RPF1's light?

I have silver rpf1's and I love them. Some people at the track have had problems with them bending though. They say the NT03+M's are holding up better. For most people this won't be any sort of problem though, as they don't constantly hop berms

 

[disappoint]

You are not comprehending sprung vs. unsprung weight. Yes if you are comparing lbs to lbs and ignoring everything else, 40lbs of fuel is greater than 32lbs of wheels. But since the wheels are unsprung they have a greater affect than fuel which is sprung weight. The formula itself is complicated and depends on many factors but generally unsprung is 2-5 times the difference of sprung. So that 32lbs in wheels can feel like anywhere from 64-160lbs difference in sprung weight.

More like 1.5-2x the difference. I'm not missing the point, I think you're all missing my point. And that is that you can increase or decrease the weight of the vehicle's sprung weight to feel what difference it would make in acceleration before buying anything. Yes of course you would have to change the sprung weight more than the unsprung weight, by about a factor of 2. And yes that is taking into account the rotational inertia.

 

[disappoint]

You are not comprehending sprung vs. unsprung weight. Yes if you are comparing lbs to lbs and ignoring everything else, 40lbs of fuel is greater than 32lbs of wheels. But since the wheels are unsprung they have a greater affect than fuel which is sprung weight. The formula itself is complicated and depends on many factors but generally unsprung is 2-5 times the difference of sprung. So that 32lbs in wheels can feel like anywhere from 64-160lbs difference in sprung weight.

I even gave you the weight of fuel and you still don't get it do you? 15 gallons of fuel weighs about 90 lbs not 40.

Can you do the conversion factor now or do I have to spoon feed it to you? FFS.

 

[JCH13]

More like 1.5-2x the difference. I'm not missing the point, I think you're all missing my point. And that is that you can increase or decrease the weight of the vehicle's sprung weight to feel what difference it would make in acceleration before buying anything. Yes of course you would have to change the sprung weight more than the unsprung weight, by about a factor of 2. And yes that is taking into account the rotational inertia.

You're still missing the whole idea. Sure, you can replicate the effect reduced rotating mass will have on acceleration, sort of.

You will not replicate the improved suspension dynamics. You will not replicate the improved steering feel. You will not replicate the difference in ride quality. You will not replicate the NVH differences.

Reducing un-sprung and rotating mass is about much more than acceleration and braking.

 

[sdifox]

Do know that the lighter bigger wheels = easier to crack them. If you live in pothole heaven, don't do it.

 

[iamwiz82]

Do know that the lighter bigger wheels = easier to crack them. If you live in pothole heaven, don't do it.

That is completely dependent on the quality of the wheel. BBS would be a lot less likely to crack than a offbrand sold at the local wheel store.

 

[sdifox]

That is completely dependent on the quality of the wheel. BBS would be a lot less likely to crack than a offbrand sold at the local wheel store.

OZ Ultraleggera with 245/40/18 tires. Cracked 2, one of them 2 cracks at once.

This is just city driving. Just potholes.

 

[Kelvrick]

OZ Ultraleggera with 245/40/18 tires. Cracked 2, one of them 2 cracks at once.

This is just city driving. Just potholes.

Ultraleggeras are pretty light at 18x8. What are they, 17lbs? And cast, if I'm not mistaken. The material is spread a little thinner than what I'm assuming the OP is looking at (17x7?)

That said, do the roads just really suck up there? I find the roads in cities that go under 32 degrees for long periods of time will really suck it up.