lightest cheapest 15"

[XDGT03]

Where are they, what are they where can i get them. i have search all over the friggen place and can't find a decent 15" rim in a 6-7 inch wide for around a hundie a piece. Those Konig Heliums would be perfect if they had the right pattern.

Suggestions?

Oh yes this is for autox purposes so I don't care about style, color, etc...

[SWortham]

Rota Slipstreams or Subzero's are both very light and pretty cheap.
I can't remember what they weigh but it should be listed here...
www.wheelweights.net

[XTRAWLD]

Hmmm, run on a bunch of spares!!! lol

Light and cheap wheels......it's hard because alot of places don't list weight as one of the specs. Good luck though.

[CaseyGT2001]

If I remember correctly, the Rota Slipstreams 15" weigh 11.8lbs. I think they are the best wieght/cost ratio.


Machiii.net sells them for 450 a set, and ships them for free
or you can get them with a set of 205/50/15 Azenis...
mounted, balanced, with hub rings, stems, and lugs shipped for 810

That's pretty good deal....

[BlackElantraGT]

Yeah I think the lightest, cheapest wheels you can get will be the Rotas. The Kosei rims on Tirerack.com were also fairly light at 14.1 lbs and $200 per rim.

[XDGT03]

Wow that is a pretty good deal. And light

Edit: disregard

I did find these Motegi's at 14lbs and around $100
http://www.motegiracing.com/applicationguide/motegiimages/big/b2028.gif

[hyunelan2]

I've heard questionable things about motegi's build-quality. Not saying they're bad, but if you're looking for a performance autocross wheel...

[BlackElantraGT]

Are you sure those are the right motegi's?? They make some of the heaviest rims out there. They do make a lightweight one but I believe the design is different from that one.

[Steve]

The Motegi Trak_lite is the lightweight racing wheel and it only has a 4x100 or 5x4.5 bolt pattern. I looked into it awhile ago, who wouldn't want this, I love flat black wheels.

http://motegiracing.com/applicationguide/motegiimages/big/b2388.gif


Icon makes a track wheel, the W63, it weighs just under 13lbs a wheel, can be had for right around $400 a set and and comes in 15x6.5, 4X4.5, 40mm. Here it is in bronze, but it's also in flat black, silver, and white.
http://www.tiretrends.com/include/get_image.php?id=2499

[XDGT03]

Let me expand on this topic a bit without starting a new thread.

I am interested to know how much hp is lost with each pound of rotational mass. In essence, what do i loose in hp if I go from a 12lb rim to a 13lb'r and 13 to 14 and so on? Is it an equal loss for each lb or does it increase exponentially with ea lb?

Here's another toughy.

If my 16's weigh say 16lb's, less than the stockers which are about 20lbs ea, do I gain, loose, or stay the same in terms of hp since it is lighter but larger in diameter. Will this matter at all since the overall diamter with the tire is about the same?

And

If I get 15's that are 16lbs, therefore smaller in diameter from what I have, how much will be gained (if any).

Also

I'm not exactly clear about the whole off set thing. Is this the distance from the center of the whell to the outer edge. So off set is the amount of the wheel sits away from it's center. So a smaller off set puts the rim closer to the car and a larger off set puts it further away? And how much will that matter with 15" and smaller diameter tires. Assuming there would be no fender rub issue, how far out can the rim set? Assuming I am thinking about off set correctly, what would the max off set be to push the rim furthest out?

[kylemorg]

About the offset -- you are correct. I believe the recommended offset is 42mm, but I read in another topic that 40-45mm works OK.

As for the HP loss, it's not that simple to calculate that when changing wheels. The distribution of the weight from the hub to the outside of the wheel/tire package makes a big difference in the amount of energy needed to spin them; for example, an 18" rim would have the wide flat part of the rim farther out from the hub compared to a 15" rim. Even with the same outside diameter tire, there's more rotational mass towards the outside of the wheel/tire with a larger rim, since all the weight is shifted further out from the hub. Unfortunately, wheel manufacturers aren't going to list that info.

I believe it's actually a function of torque instead of horsepower, but I don't remember enough physics to give you the details. However, generally the lightest and smallest diameter rim will have the least resistance to acceleration/deceleration, which is part of the reason most autocross cars don't use huge wheels. If you go from 16lb 16" rims to 16lb 15" rims you should gain a bit of power at the tires.


Of course, handling on pavement is better with a larger rim and lower profile tire, though.

Interestingly enough, Car and Driver (I believe) had an article a few months back about the super large aftermarket 20+" rims they're putting on SUVs causing problems with braking and quick steering due to the mass shift towards the outside of the wheel/tire assembly!

[BlackElantraGT]

I can't give you some mathematical equation for this issue, but after driving stock wheels for 2 years, and then switching to bigger, lighter forged rims, I could instantly feel the difference in acceleration.

[XDGT03]

but after driving stock wheels for 2 years, and then switching to bigger, lighter forged rims, I could instantly feel the difference in acceleration.

See that goes against convention. You should have actually felt slower off the line for 2 reasons. First, the larger diameter means the wheel has to rotate further to go the same distance. Second, the weight, even if the same or lighter overall (which it is probably heavier with 17" wheels and 17" tires), it pushed further away from the hub or the wheels rotational axis. I wonder if what you are feeling is more stability with wider/larger wheels and that makes the car seem like it is moving faster?

[BlackElantraGT]

Alright I don't have exact figures for the OEM MXV4 Plus tires but I will use the AVS ES100 weight to compare. In stock size the tires way 19.91 lbs. In 215/45/17 they way 23.1 lbs. That is about a difference of 3.19 lbs. Stock alloys weigh more than 20 lbs. My rims weigh less than 13 lbs. Even with the added weight of the bigger tires, I'm still saving at least 4 lbs per wheel. This is a conservative estimate, as I don't know exactly how much the michelin tires weigh nor do I know the actual weight of stock alloys. The mass of the wheel may be pushed further out because of the bigger rims, but I'm still saving enough weight per wheel to offset that.

[Bnystrom]

Horsepower is constant with a given engine and changing wheel/tire weights has no effect on it. What changes is accelleration and decelleration, since the heavier wheels/tires take longer to accellerate at a given HP output and longer to decellerate at a given brake force, due to higher rotational intertia of the wheels/tires and to the slight increase in overall weight (and inertia) of the vehicle. However, it will have the same top speed as a vehicle with lighter wheels/tires; it just takes longer to get there. At a constant speed, wheel/tire weight is only relevent to handling, since they are unsprung weight.

Reducing wheel/tire weight is a way to increase accelleration without having to increase horsepower at the engine. It's certainly a worthwhile thing to do and I will eventually do it myself.

[kylemorg]

Good summary, Bnystrom. I was rambling above since it was almost 2 AM. Inertia was the word I was looking for!

[jameswing]

The thing to look at is the tire diameter not just the wheel size. you can have a larger wheel but a smaller overall tire diameter.

Here is an example using Nitto 450s:
P205/55 R16 have an inflated dia of 24.88" [16.16 sec]
235/40 ZR17 have an inflated dia of 24.41" [16.12 sec]

For weights, you need to look at the total change of weight not just the rims. If you are goign to a smaller tire it will probably weigh less, how much does this offset the weight of the wheels, also remember that Al weighs roughtly 1/3 as much as steel.

As far as rotational speed. If the rotational speed is the same a larger radius will cover more distance and travel faster; however, it will require more torque.

Think of 2 objects in geosync orbit one a mile above the other. If they are staying in sync then they have the same rotational speed. The higher one has a longer distance to travel in the same amount of time so it must travel faster.

I'm gonna try to find some formulas to show the point.

Edit:

I found a program that runs a simulated drag race.
http://performancesimulations.com/dndemo.htm
I have attached the results forms with 205/55-15s (23.88") and again with 215/45-17s (24.62"). With all of the other settings the same (their generic settings).

The 15s ran a 16.09, and the 17s ran a 16.21.

[XDGT03]

Black, I apologize. I did not see when I posted you had the Volk wheels. When you said 17"s at 13 lbs I about ****. Now I know why. shoulda looked. That means you decrease the relative dead weight by about 128lb's. That is as much as half of what jay stripped from his car. Your tires are bout 3-4 lbs heavier because of the diamter. Had you stayed at 16"s, you may have actually doubled your realtive dead weight. Probably not important to you but it is what I'm trying to factor.

james, thanx for those results. They should be able to be "rule of thumb" applied. So for 8/10"s increase in diameter, it cost approximately 1/10 of a sec in time.

[jameswing]

That didn't take into account any weight issues though. My main point is that it's not just the size of the wheels, but the overall diameter of the tires. Even though most of the time they are related, sometimes they can have an inverse relation.

[BlackElantraGT]

Performance wise for our car for daily use 16's would probably be the best compromise because you have more tires with stiffer sidewalls to choose from, and the rims and tires won't weigh as much as 17's and above. In the end it all depends on your application. If it's going to be for drag then you'd probably want the 15's for the quicker acceleration. If it's auto-x or track use, I think the 16's might be better suited. Tirerack did a test where they plus sized the wheels from 15, 16, and 17" and in the end, they got the best track time with the 17's. Their test seemed legitimate but the only thing that I believe they didn't mention was the weight of each rim and tire. Otherwise everything else remained constant. I went with 17's for the looks and if I had to sell my rims, I'm sure more people would want 17's than 16's.

[SWortham]

For those who don't visit EGTClub, this exact same discussion is going on there. While this is somewhat on a tangent, here's a summary of what I discovered today which cleared up some confusion...

Technically wheel weight does not affect whp. However, the actual dyno results you get with different wheels will depend on the dyno (whether it's a steady-state dyno or an inertia dyno). For example I found out that a DynoJet is an Inertia dyno, which will calculate horsepower based on acceleration even though acceleration isn't a part of the horsepower formula -- strange, isn't it? So, with a DynoJet, wheel weight does affect the 'whp' results. But I don't know if it affects the horsepower results as much as it would affect real world acceleration because the DynoJet drum may provide more or less resistance than actual acceleration conditions on the road. Anyway, the DynoJet is one of the more popular dyno's out there, and yet it doesn't even calculate horsepower properly. And that can create hidden variables when we try to compare engine performance gains between different cars. But the fact that it takes so many variables into consideration and can produce repeatable results can be helpful for gauging before & after performance gains.

Read the section "Results from each type" here:
http://home.iprimus.com.au/stevebm/Dyno_Info.htm

And this article:
http://www.awe-tuning.com/pages/faq/awefaq_main.cfm?FAQ=22


In my opinion, it just doesn't make sense to try and reference the DynoJet's way of calculating 'whp' when there's a lack of a standard between Inertia dyno's. So in reality, it would be more practical to ask what difference in 0-60 acceleration or 1/4 mile time you could expect based on wheel weight, because it will not affect actual whp. I'll try to create some estimates at some point if nobody else is going to.

[Steve]

Though 1/4 mile times may be a better way of calculating horsepower, seeing as the engine is moving a specific weight a set distance in a measured time. Dyno horsepower numbers are really only good for two things. Tuning a car, ie adjusting the timing resulted in a 2% horsepower increase or for bragging rights, ie this is the only S2000 to break the 600whp barrier. Who cares, how does it perform on the track and on the street?

[SWortham]

"Though 1/4 mile times may be a better way of calculating horsepower, seeing as the engine is moving a specific weight a set distance in a measured time."

The point is that you're not calculating horsepower, you're calculating acceleration. Dyno's cannot be used to calculate real world acceleration. That's why the 1/4 mile should be a better standard.

I just had an idea of how I should do this. I'll write a little Flash application where you can feed it some #'s to produce results. It might take me a few days and it's going to take a lot of guesstimates, but it should work assuming I can relearn some Physics.

[Steve]

I found this from a Tech Article I remember reading in SCC

Rotational Inertia
The rotational inertia topic was so big, it took me two months (June and August '99) to get it sorted out. Here's the deal: There is this rule of thumb among racers that adding weight to something that rotates is far more detrimental to performance than if you add it to the body of the car. This is absolutely true, and by bumbling through some physics, and after slipping and falling on a radian, I managed to get a few formulas figured out that could tell you just how much worse.

Any moving object has kinetic energy, as does an object sitting in place and rotating. An object that is both rotating and moving (like a rolling wheel, for example), has kinetic energy from both, meaning that accelerating or decelerating that rolling object will take more power than one that is just sliding along. How much more power is the question.

The answer, it turns out, depends on how the weight is distributed on the wheel. An extra pound on the tread of a rolling tire has as much kinetic energy as 2 lbs on the floor of the car. As you move toward the center of the wheel, the rotational effect drops until, at the center, a pound is just a pound. The formula I derived to determine the exact relationship between weight on a wheel and weight in the car isn't worth repeating here for one simple reason. It requires that you know the moment of inertia of the wheel, and measuring that is virtually impossible. What you need to know is that changing to tires that are 1 lb heavier will effectively add 8 lbs to the car (four tires, remember) and that adding a pound to the wheels will effectively add somewhere around 6 lbs to the car.

That only considers acceleration and braking; handling is dramatically affected by unsprung weight as well, but no simple formula is going to tell you how big the effect is.

http://www.sportcompactcarweb.com/editors/0109scc_techno02.gif


The one useful formula that did come out of my diatribe on inertia was the effect of a light flywheel. Because the flywheel's rotational kinetic energy is directly linked to the car's motion (through the gearbox), you can also calculate the effect of a lighter flywheel. Here's the formula: Next month, we will tell you all about the aluminum FocusSport flywheel we just put in our Project Focus. Until then, know this: The flywheel is 12.5 lbs lighter than stock and has a radius of 5.5-inches; the Focus' first gear is 3.667:1, the final drive is 3.82:1, and the tire radius is 12.1 inches. What's it all mean? In first gear, the car feels more than 250 lbs lighter!

[SWortham]

What you need to know is that changing to tires that are 1 lb heavier will effectively add 8 lbs to the car (four tires, remember) and that adding a pound to the wheels will effectively add somewhere around 6 lbs to the car.

OK, maybe that's good enough. You could apply that rule of thumb to my 0-60 calculator and get an idea of what that translates to in acceleration... www.gldomain.com/accelerationcalc

[Steve]

I also saw on HMAservice that the stock Elantra wheel/tire assembly is approx. 30lbs.

[bcware]

Obviously wheel weight will ALWAYS affect whp. An overall lighter vehicle will travel faster as it becomes lighter and the engine remains constant in power. Front wheel drive is crap.

Taking common sense into consideration after viewing most practical applications like drag racing and high end sports cars which all have smaller rims in the back (rear wheel drive applications) it should be easy to come to the conclusion that the wheel delivering the power will work best with a smaller but wider rim, however there have to be diminishing returns otherwise why would we stop at around 15 inches? the returns are probably very small after a certain size.

New thought, more than likely what limits the minimum rim size and maximum tire size is probably the side wall strength of the tire. we can't simply make a 6 inch rim and keep a tire with gigantic side walls to take up the remaining size. The tire would obviously become flimsy and fail after a certain size.

[Steve]

Obviously wheel weight will ALWAYS affect whp. An overall lighter vehicle will travel faster as it becomes lighter and the engine remains constant in power. Front wheel drive is crap.


Just to be clear it will affect whp, but it won't increase it. If you have a 2500lb XD and it makes 140hp, then you take away a total of 50lbs, it still has 140hp, it just has less load to move, so it can do it faster. The point of this thread is that the more weight you can take away from the wheel/tire assembly the better, due to rotational weight and unsprung weight. A 17" super lightweight wheel with a really high performance tire would probably be the highest handling combo for an XD, but that would cost a lot. If you really want a car to handle and accelerate, the cheapest way to do it is to remove all the extra weight you can.

[bcware]

Last thought, i'm sure i'll get "burned" here by saying less weight increases whp, i think someone mentioned it wasn't in the forumla? whatever, you still get the idea... a lighter car is a faster car.

[SWortham]

Obviously wheel weight will ALWAYS affect whp.

LOL. I wish people would stop saying that. Wheel weight will not affect whp, it will affect acceleration. I know that might fly in the face of common sense. But consider this...

Horsepower = (Torque * RPM) / 5252

That's the formula for horsepower. There's nothing in that formula that has anything to do with acceleration. The true way to calculate wheel horsepower involves bringing the wheels to a constant speed and measuring the torque output at a certain RPM. The links I have posted explain all of this in detail.


whatever, you still get the idea... a lighter car is a faster car.
Exactly. :D

[bcware]

actually you could increase whp by getting better rims. say a 10 inch wide rim versus a 7 inch wide rims... haha that would increase surface area, grip and horse at the wheels. weight must be a factor in WHEEL horsepower, but not in the engines horse it self. let's get all crazy here and break out the physics books and tear me a new asshole. i'm sure there must be hundreds of websites explaining this entire thing... someone link one.

yeah like i said that formula is just for horsepower, not power at the wheels.

[Steve]

The only thing I disagree with is the smaller wheel, wider tire argument. Corvettes for instance have 18" wheels up front and 19" wheels out back, for better handling and power delivery. High performance RWD cars have taller sidewalls out back because they are so wide and the sidewall height is a percentage of the width. Your argument works for drag cars, but for handling, the larger the diameter of the wheel, the stiffer the sidewall, the better the handling. In XDGT03's case, if he can only afford 15" wheels then he should get the highest performance tires he can get for that size.

[bcware]

what might help me even more is actually reading the previous posts...
one step at a time.

yeah true about the applications... but drag racing is completely different than say normal driving. drag racers only go straight so they drop as much weight in the front by having tiny lightweight rims... while terrible for handeling all they do is function to turn the car only slightly.

[SWortham]

"yeah like i said that formula is just for horsepower, not power at the wheels."

No... horsepower is not tied to just one function. It is a physical unit of measure. There is horsepower as it is measured at the crankshaft, and there's horsepower as it is measured at the wheels -- both are determined from the same formula. It took some reading for me to figure this out.

Check out my first post here, I listed a couple of sites that explain how dyno's measure hp.

[bcware]

OK you win, i don't care anymore and it's drifting off-topic anyway. :znaika:

[SWortham]

Well I think the question has finally been answered anyway. Using the rule of thumb Steve posted and my acceleration calculator, you should be able to come up with a good estimate.

[XDGT03]

Ok, so with we have "learned" can we apply it.

I have 16" wheels that weight 16lbs. I have Kumho tires that weight 21lbs. TOTAL WEIGHT 37lbs. If I reduce the tire weight by 3lbs each. that is 12lbs total X rule of thumb 8 dead lbs. That is 96lbs. So I would essentially have a car that weight about a 100lbs less. That is significant but barely.

Now going to a 15" wheel and tire that reduces the overall w/t weight to 30lbs each would mean that effective "dead" weight would be reduced by 224lbs. That is more significant. But still not dramtically. So here is the question, can we add in the smaller diameter which allows the mass to rotate with less hp used, less unsprung weight, reduced ride height of approximately 5/16" ....cut 2 seconds off my lap times? Because that is really where i need to be in STS to "WIN".

[silet]

I still think you should go for 14" alloy rims and 1" shorter tire (205/55/14).

Just so people don't start on the Physics BS and try to stay on topic... reducing the weight and diameter of the tire/wheel will reduce the parasitic horsepower loss from the crank to the wheel.

So you'll be using more of the 135 hp Hyundai gave you (that's not including your mods) :tongue:

[Steve]

SoloII is about handling and driver skill, freeing up a few extra horsepower has negligible effect. If you want to make for a faster drag car, go with smaller wheels and wider tires. You already have a fairly good compromise of weight/money in a 16lb 16" wheel. What Kumhos do you have?

EDIT: have a look at the last results from my local AutoX Speed Weekend SoloII (http://pmsc.on.ca/results/2004/sws.html)

The top contenders (except the RX8 with stock 18" wheels) all have less than a 150hp and smaller stock wheels. Dan Demers' is first because of driver skill, the Miata has Falken Azenis RT-215, the Neon has Kumho R compound, the '92 Shadow had brand new Dunlop FM901's, it's seriously almost entirely driver and tires. You really want to win? Buy two 15" wheels, something around 13lbs and buy two 225/50/15 Kumho Victoracer R compound tires. Or if you need something streetable, buy four Falken Azenis RT-215 in the 215/45/16 size.

[XDGT03]

I have Kumho Ecsta KH11's. I will say that they are awesome tires. I have driven the **** out of them and the are really, really good. I will say that when I lowered may car with the H&R springs they were a bit less predictable at the limit. The limit was very high. But, once I put in the camber bolts and set the neg in front and rear, they became extremly stable again. I HIGHLY recommend these tires.
http://www.kumhousa.com/images/Products/Tires/KH-11.jpg
http://www.kumhousa.com/Products/PtnDetails.asp?CatID=7&mainCatID=1 (Kumho KH11 info)

I agree that it is about handling and driver skill. I 6 races my skill level has increased from dead last to the top 70%. The times are just not far off to get to the top 85-90% of the field. I figure I can get there by improving my skill. But to get to the 95-100% I need more. I am not trying to substitute "stuff or $" for skill. The reason I started this thread was because I was going to be buying Azenis or MX's for next year. My concern was that I was going to spend >$350 on these tires for 16" rims when maybe there would be an overwhelming advantage to running 15"ers. I guess I haven't yet seen the overwhelming advantage yet. there is no doubt that it is an advantage, but if it is not going to get me to 95-100% then I will just get the 16" tires and save the rest of my money and be happy coming in consitantly at 85-95%

[Steve]

What springs and struts do you have right now?

[XDGT03]

I edited my last post and added that info while you added this. H&R and stock struts.

[Steve]

Ah, get the Tib GT struts, it will add a lot of handling to the package. In the Canadian SoloII rules, the stock class cars can have upgraded struts, al lthe serious contenders, take the two allowable mod points in the form of R compound tires and add the allowed non-adjustable high performance struts/shocks.

[XDGT03]

That is a good suggestion since I don't want to go with lower springs. Our roads a just too horrible in MI. But that does mean I have to get new lowering springs tho, right. To fit the tib struts and perches?

[Steve]

I don't think so, you'd just need the Tib Ultrasport shocks and the mounts.

[Elantra2.001]

The further out the center of mass of a wheel is, the more power is required to accelerate it. Just so ya'll know, this applys to brakes as well. Having larger rotors means that the center of rotational mass is put out further on the wheel, so it repuires more power to accelerate the wheel at the same rate as a wheel with the weight closder to the center. Torque is a twisting force. How much can this engine twist at this RPM. Horsepower is how much work can it do. This is a function of horsepower and RPM. So the higher the torque, the more the engine can pull, but the higher the horsepower, the car accelerates and the more work it can do.

[SWortham]

I found another 15" x 7" wheel that looks great, weighs in at 13.2 pounds, and should stand up to some abuse.

Team Dynamics Pro Race 1
http://outmotoring.com/cgi-bin/image/templates/Pro_Race1_White_md.jpg
http://www.mini2.com/gallery/personal/Msfitoy/38665.jpg
http://outmotoring.com/team_dynamics_pro_race_1.html
http://www.bimmerworld.com/html/team-dynamics-pro-race-1---15.htm

The only problem is that I'm not sure where to get the right offset & bolt pattern. According to www.teamdynamicsusa.com they make this wheel with 4x114.3 and 42mm offset, I just haven't found a place online that sells it.

[DocRxGLS]

I had considered getting these Rage Breakers just because I like the simple design, and I found out from tiredirect that they weight about 15 lbs. It says they will not fit, but I found out if you remove the screws in the front brake calipers, they wil fit (seems like most people have done this and said it is ok to do). They are 15x6.5 +40 offset in the 4x114.3 pattern. $77/rim

I think I am going to get the 5Zigen (pronounced go-zee-gun) RX-6 in the same configuration as above (15x6.5 +40, 4x114.3). Once again, caliper screws will have to be removed. They make silver or hyper black (getting silver for my Black GLS). Best of all, they include metal hubcentric rings. Tire direct said 15 lbs for these also, but I had emailed 5Zigen America a while back (RX-6 not listed on their website), and they responded back a couple weeks later and said it was either 10.2 or 12 lbs....forgot which, sorry. $128/rim

I think I am going to wrap them in Yokahoma Avid V4S 205/55 15's. They have good all around ratings, and a long tread life. The steelies will get a winter tire.

[kylemorg]

To reference back to the earier discussion about the center of inertia, which is the main factor in the wheel's resistance to acceleration / deceleration, I found this page that discusses how to measure that factor analytically for a wheel and tire combination:

http://www.analyticcycling.com/WheelsConcept_Disc.html#Wheel Rotational Inertia

If you were switching between 15" wheel and tire combinations and had one wheel/tire combination of each, you could use this method to see which one would have less inertia. You'd have to weigh each wheel & tire combination, too, since this calculation only gives you the center of inertia, which you need to multiply by the weight to get the relative amount of resistance each combination will give you.

my new Sokudo 17" rims with Kumho Ecsta 711 205/40R17's weigh 39.5 lbs each. I haven't checked the center of inertia yet.


I haven't weighed or tried the COE measurement yet on my factory rims with the 195/60R15 Dunlop SP Sport A2s; I'll post the results later.