Painted Wheels

[adsense_id=”4″]Recently there were some discussions on the Z3 message board regarding painting wheels. In response to that discussion I went through my Z3 photo collection looking for photos people may want to see in regard to wheel color and/or painting. In this first photo the owner found some aftermarket wheels that already matched the color of his car (no painting required).

Okay it’s not really painting, but chroming wheels is another way to change the look of your stock wheels. In my opinion chrome adds to the retro look of the Z3, this picture jumped out at me as I was going through my collection because the white and chrome combination looked so good.

If I owned a white Z3 (and someday I may), I would consider painting the wheels white just like this M owner has. The white on white look is fantastic (in my opinion). It reminds me of the early 80’s Porsche 944’s that apparently had a white wheel option if you got the white exterior paint.

Not sure if it’s the quality of these photos or the specific lighting in these photos, but personally I would be after a more flat white look (but that’s just me chasing my memory of the old Porsche white wheels).

Now at the other end of the spectrum (sorry couldn’t resist that pun) we have black wheels. I’m sure this look is very hard to photograph, but these photos don’t appeal to me because you can’t make out any details of the wheels.

You can see more details of the wheel in this photo. Maybe its the matching black exterior paint but this photo makes the black wheels look better than the previous photo. Notice how the dark paint makes the disc brake stand out. Some red caliper paint would really stand out.

SSR Competition Wheels with Kumho V700 Tires

Subject: SSR Competition 17″ x 8.5″ Wheels
Kumho Victoracers V700 225/45-ZR17 Tires
Cost: $ 2,118
Good: Sticky, Light Weight, Good Cost vs. Performance Ratio
Bad: Dedicated for racing – off goes the stock system and on goes the racing system and repeat. Plus, I need to put on a “GASP” trailer hitch and pull a trailer with my Z!!!!
Installer: Mounted, Balanced & Heat Cycled by The Tire Rack. Mounted on car by yours truly

When I started autocrossing my car, I used stock 16″ tires & wheels, even though I race in the ASP class in North Carolina & Virginia, which allows for larger & wider systems. I found myself a consistent 2 seconds back from the winner. So I promised myself that I would go to the next step to start winning some races if not close the gap, by purchasing a tire/wheel set for autocrossing.

After viewing past posts on the message board and the Tire Rack Q&A section. I made a list of things that I expect from this investment.

1. Best Cost vs. Performance ratio for the tires & wheels

2. Best Lightest weight vs. Strength ratio for the wheel

3. Capable to rotate tires from front to back to maximize usage

Wheels: The list of wheels I looked at was BBS RK & RX, SSR Integrals, Forge Lines, IFG, and various other lightweight track wheel manufacturers. I wanted my wheels to be spoked, so that the maximum amount of air can cool the brakes and make it easy for me to clean the wheels. I came close to purchasing either the SSR Integrals or the BBS RKs. But this past Christmas, I saw those new SSR Competitions and saw the estimated weights and costs and I was sold on them. After calling Aaron of The Tire Rack (www.tirerack.com), we determined that the 17 x 8.5″ wheels would work for me. I want the wheels to be the same size all the way around so that I could rotate my system from front to back. Aaron informed me that he weighed one of the wheels and it came in at 15.1 pounds. Now I could not verify his weight, because, I had Aaron mount and balance my system before shipment. The cost of the wheels was: $ 365/ea

Tires: The list of tires were of-course Hoosiers, BF Goodrich, & Kumhos. Since the Kumhos were the least expensive tires and the “new-kid-on-the-block” for track tires, I searched the website for people that has experience with these tires & The Tire Rack has an article on how to use the V700. I found that they were satisfied with the purchase and any down falls were minimal. This was good news for me, because of the Kumho’s low cost versus the other brands’ high costs. I originally wanted 235/40-ZR17, but after looking at the Tire Rack’s ad and talking with Aaron, I had to be satisfied with 225/45-ZR17 tires. Kumho does not offer a 235 in the V700s, only 225 & 245. I also had The Tire Rack heat cycle the tires, so that they will be ready for racing. For those persons who do not know what heat cycling is, The Tire Rack has a good explaination. The cost of the tires was: $ 130/ea, The cost to heat cycle them: $ 15/ea.

When the system arrived it was nicely packaged so that the wheels would not be damaged during shipment.

The wheels also included mounting bolts that works with the SSRs and a center hub adaptor to make the wheel hub centric. Now I would rather wished that SSR made the wheels dedicated to the BMW, but that is only wishful thinking. I do love the look of those center adaptors. They are made of aluminum and anodized black with the “Mille Miglia” logo printed on the surface.

Conclusion: I did a brief drive around my neighborhood. Of course I could not do any speed trials or see how she corners. I did not feel like using up my tires before I could race them. But, I can say this, that I could tell the difference in stiffness and stickiness of the rubber – – WOW! All due to the larger rim diameter, thicker sidewalls & slower durometer of the tires. I will give an update later during the racing season after I have a couple races under my belt with these new tires and wheels. Plus, I might bring home a trophy =:o

Update: I recently talked to my friend who autocrosses a Mustang 5.0L in the ESP class and he told me I could use the 245 on an 8.5″ wheel with no problems, because he does. I guess I know what tire size I will be purchasing next.

Hartage Classic Wheels

19″ Hartage Classic’s Wheels

19″x8″ (front)

with 235/35/19 Yokahama AVS Sport

19″x”9.5 (rear)

with 265/30/19 Yokahama AVS Sport

Z3 Safety Shell Exhibit

Z3 Safety Shell Exhibit

2.8 with ///M Wheels

2.8 with ///M Wheels

Both Front and Rear ///M Wheels

Four Front ///M Wheels

Michelin Pilot Sport Seen On a 2000 2.8

Visited the local BMW dealership yesterday, and while waiting for theie service department to take a look at my car I had time to walk the lot and take a look at the local Z3s. I saw a few things I had not noticed or seen before so I thought I would share them with you. (click on the pictures for a larger view).

Over in the used car section they had about eight Z3s, most appeared to be 1996 and 1997 models. This particular white Z3 had a black pinstripe that started on the hood and looped around the back of the car in the area between the cockpit and the trunk, finishing on the other side of the hood. Interesting look, but small sections of the stripe were missing so it looked kind of tacky to me.

Further down they had a white M roadster with a hardtop. This is the first time I had seen this particular combination. All the windows had dark window tint including the top section of the front windshield. The interior was red, which I think looks great with the white exterior.

They even had a couple used boxsters on the lot. A salesman approached me and asked if I would like to take a drive. I told him my M roadster was in the shop and I was just killing time but he offered one more time so I decided to take it for a ride. It had been a long time since I test drove a boxster and I was killing time so why not. When I tried to lower the top it didn’t work, salesman said some parts were on order. I started it up and kind of chucked at the squeak the clutch made, it was almost as bad as the squeak my clutch makes. Driving it off the lot I was reminded how much I hate the transmission in these things. Shifting from first to second feels like a foot long throw. The acceleration is good (but not M like), however the exhaust note was great. Handling felt similar to the Z3, except the boxster felt bigger. Lots of interior squeaks and rattles hinted to me that this particular boxster needed lots of TLC and I was surprised to see it only had 20000 miles (felt older). After the test drive the salesman said I could move from the M to this boxster for not much additional money, because they only wanted 42,000 for it…. I told him I would stick with my M.

Speaking of overpriced cars, can you believe this M3 Convertible with chrome wheels had a 52,000 dollar sticker price. Ten grand more than an M roadster or M coupe, somebody explain this to me.

Saw this beautiful steel gray 2.8 with the 17″ tire package that hadn’t even been unwrapped from shipping yet (note the temp cover over the top). One very interesting note is that this 2.8 had the new Michelin Pilot Sport tires on it, I assume this is a hint that the future 2.8’s with the 17″ package might get the new Pilot Sports as well. As an M owner I should point out that it appears the 2000 2.8 now comes with far superior tires than the M roadster’s Dunlop-sided SP8080 tires.

Made one other observation that I hadn’t noticed before. The 2.8 lower bumper has body colored paint in the front grill while the 2.3 has an all black grill.

BFGoodrich G-Force T/A KD

Before you read this article, let me tell you a little bit about my vehicle: It is a 1998 Z3 2.8 with the 17″ tire and wheel package from the factory. Suspension modifications include the HMS strut brace and the RD sway bars.

As I watched the soft tread on my 17″ Michelin MXX3 Pilots quickly fade away practically mile by mile, I knew soon that new tires would be necessary. It was just the rear tires that had lost the tread, as the fronts still had a nice amount left. Because of the staggered sizes used on the Z3 2.8 17″ wheel package, which happen to be the same as the M roadster/M coupe, with the front tires smaller than the rears, tire rotation is not a possibility.

Replace just the rears?

Since the fronts still had tread left, I questioned whether it would be feasible to replace just the rears. The 245/40/17 size is no longer available from Michelin for the MXX3 tire. Thus I would have to either go to 255/40/17 or change all four tires. I decided, based upon reports I’ve read on the message board, that I did not want to increase the size in the rear as it may negatively (or positively) affect handling characteristics, and may detriment the effect of ABS and ASC+T. I finally decided that I would get four brand new tires to replace the worn out rears.

Tire Types

The first thing that I needed to determine before I went shopping for a tire was what kind of tire I wanted to get. A summer tire, a winter tire, all-season tire, a cheapo tire that fits, etc. Only you can decide based upon your driving habits and weather conditions what type fits you best. Living in Miami, and never seeing snow, I decided that I wanted to get an all-out performer, similar to the standard MXX3 that came with my car from the factory. Rain, while frequent in the summer months, never lasts long. The hot sun dries the water up after any rainstorm. Thus wet performance would be appreciated, but would not be at the top of my list. After all why buy a drop-top if you like rain so much? 🙂

Tire Choices

The first place that I went to check information regarding tires was the TireRack. They offer online ordering of tires with great prices plus plenty of information on cars, tires, etc. Under their “Maximum Performance” category I looked at several tires, including: Bridgestone S-02 PP, Dunlop SP Sport 8000, Pirelli PZero, among a few other brands. The tire that caught my eye was the BFGoodrich G-Force T/A KD, as they had intense neon colored advertisements of achieving never-felt before “g-forces”, hence the tire’s name.

Research Into the G-Force

I began to do some research on my own to try and verify BFG’s claim on their brand new tires, which were introduced some time in November, 1998. The first place I checked was, naturally, the TireRack. In their preliminary review they tested the tires on two cars on the track, a Porsche 996 and a Corvette. They said that the G-force tires practically eliminated the oversteer problem that the rear-engined Porsche cars are famous for, and provided a significantly higher amount of grip then the Pirelli PZero tires already mounted on the car. This was starting to look good, a tire that provides a significant increase in grip than the already ultra-grippy PZero? Then they tried it on the Corvette, stating that it was easier to drive the car harder and faster. Read the review at the link above for details.

Another ad that caught my eye was one that was in the January 1999 issue of Car and Driver. Showing a yellow M roadster, BFGoodrich proclaimed that their tuned M roadster with stock size G-force tires provided 1.05g of lateral acceleration on the skidpad. That is a lot of lateral acceleration, more than many many supercars out there. As the tread on my Pilots were wearing down, I was getting more excited to see what it could do to my “tuned” Z3 2.8 (swaybars).

A Bit More Research…Found by Surprise

As I was roaming through the January/February 1999 issue of Sports Car Magazine International, I accidentally stumbled upon an article on…you guessed it: the G-force T/A KD tires. It was written up in their “New Technology” section. Basically they stated that it provided more grip and increased the ability of every car they tested it on compared to the other tires that were on the several cars they tested, including the Bridgestone S-02 PP, and the Pirelli’s. I was not surprised. They even went on to say that this was practically an autocross/racing tire and that it should have been standard on the Corvette had the engineers had their way, as it would have made that car much better in stock format.

A Little Bit About This “Technological” Tire

The BFGoodrich G-Force T/A KD tires are pretty impressive in the amount of technology they have imbedded into the tire. Designed for dry traction primarily, the “KD” stands for, or so I have heard, “killer dry”. This is BFG’s first asymmetric street tire. That means that you need to have a different tire for the left side and the right side of the vehicle. A negative aspect in terms that you can’t rotate the tires even left to right, but positive in the aspect that it increases handling significantly. By producing asymmetric tires, BFG increased the “contact patch” of the tire significantly by optimizing one side of the tire for turn opposite to the side it was on. For example, if you are turning right, you want the most traction at the edge of the tires. On the left side of the left tire is the dry traction part, and the right side of the right tire. Using this technology, the contact patch of the G-force tire is 79%! If you don’t know what that number means, it means that this is one of the most connected tires to the road in existence. Even many other max performance tires don’t even come close to that number. The rest of the tire is optimized mainly for wet traction and high speed stability. The speed rating of the tire based upon TireRack and BFGoodrich’s site is “Y” rated, which is 186mph. This differs from the standard and expected “Z” in a performance tire, at least it did to me. However “Z” is defined very nondescript: 149mph and over. So what is better, Y, or Z? More on this later below.

Time To Order

Everything I had read about this tire sounded like it was too good to be true. They last longer than the Michelin Pilots accorded to the UTQG tread wear rating (140 vs 200), cost less, are available in the stock Z3 2.8 17″/M sizes, and perform better. I decided to order from TireRack. Service was superb and the tires arrived at the tire shop via COD order exactly as directed. The two front tires I received were both built the same week, and the two rears matched build weeks as well. Just 3 (or maybe it was 4) business days later the tires came and it was time to go get them mounted and balanced. Note to other Z3 drivers: unfortunately these tires don’t come in any 16″ size. The minimum size would be the 17″ wheel package, making it available only on M roadster / M Coupe cars or the Z3 2.8 with 17″ package, it is unfortunate that they do not offer a 16″ size and maybe on the basis of thisarticlee they will. To my surprise, the tires all had “ZR 91Y” written on the sidewall, as opposed to “YR” as indicated on the TireRack site. Either way though, no roadster driver will ever bring their car this fast and it is nice to know that under every condition you could physically do these tires will handle it.

Enough Talk Already, How Does It Drive?

Well let me just say this… If to you, Happiness is the corner, not around it, then these new BFGoodrich tires ARE happiness! They are that good. I will tell you a bit more about it in the categories below, but, they are superb. The second I took the car out of the tire shop, turning out at even 5mph, I noticed an immediate difference. If you are considering any other tire to replace your worn out Pilots, or are unhappy with the Dunlop 8080E’s, this is the tire to get.

Dry Traction

The dry traction of this tire is superb. Far exceeding the abilities of the Michelin Pilot MXX3, this tire knows how to stick. And stick, stick, stick it does. Acceleration had a noticeable increase in speed. But acceleration is not where this tire really shines, but it is the reverse. This tire likes to STOP, and STOP it does now. I performed several braking tests within the same day with both the Michelin Pilot MXX3 and the new full tread G-forces with barely a few miles on them. From 60mph, when flooring the brake pedal with the Pilots, there was considerable bite and the car stopped quickly, with the ABS kicking in and locking up most of the way down. I repeated this test, from 60mph, with the G-forces. I was amazing at the difference the G-force offered. The ABS did not kick in in the 60 to 0 test as the tire did not loose traction. I tried it again to make sure I was pressing hard enough and it did not loose traction, thus the ABS did not need to be activated. Not only did the brake pedal feel firmer, the car felt like it was stopping quicker, and I am assured that these tires have reduced the already short stopping distances of the Z3 to something even shorter. I then did a 70mph to 0 brake test, with both tires. With the Michelin Pilots, there was grip except not so as much as there was at 60. The car stopped formidability, however the ABS was anti-locking the entire way down. On the 70 to 0 test with the G-forces, the tire just seemed like it had more bite. The ABS did not go on immediately however. Once I was almost done with the braking session and stopped I felt the pedal pulsate, but it was only for a very short amount of time, considerably less so than the amount of time I felt the pedal pulsate with the Michelins. I am convinced that I now have a safer car and better active ability to prevent an accident. Also, the car is no longer as sensitive to wind when traveling on the highway as it was with the Pilots. This same effect can be felt when going over a bridge. In every car I’ve been in, over the bridges between Miami and Miami Beach the cars always go a little left and right for the split second when you are over the metal grating. I did not feel this effect for the first time in my life in a car, as the tires just took it and the car exhibited no sideways motion.

If you have ever driven another car besides the Z3 for a few days, and then return to the Z3, the brake pedal always feels somewhat strange at first because it is so much tighter than practically any other car. Well this is the feeling that I felt with only changing the tires from MXX3 to G-force. It is amazing how much the tire affects the feeling and characteristic of the entire car.

Rating for BFGoodrich G-Force T/A KD in Dry Traction: 10/10

Rating for Michelin Pilot MXX3 in Dry Traction: 9/10

Wet Traction

After living with the G-Forces for several weeks, and in rainy weather, I can definitely say that these tires are great in the rain. Their resistance to hydroplaning was outstanding and dry traction even in the wet was still superb, and offered very similar feel then what was described in “dry traction”. Even in standing rain, under heavy acceleration or heavy cornering, the tire sticks to the wet ground without any tail wagging, and the traction control light never went on once during any of my tests. These tires perform far greater in the wet than the Michelin MXX3s do, and I was vividly surprised to see that the new tires do so great when I did not expect them to be so perfect based upon their tread pattern.

Rating for BFGoodrich G-Force T/A KD in Wet Traction: 9/10

Rating for Michelin Pilot MXX3 in Wet Traction: 5/10

Cornering Traction

I thought nothing would come close to the Pilot MXX3 in this category after driving them for 13,000 miles on my Z3. Boy was I wrong. The Pilots are snow tires compared to the G-forces in this category. You may have heard of the problem with the Z3’s rear suspension and its natural tendency to understeer, as it is an older technology derived from the E30 M3. In my opinion, this tire has fixed this flaw with the Z3. I can’t state how it would do on a stock car, as I have the Racing Dynamics Sway Bars, but even with them on and the Pilots I could understeer easily by giving a nice amount of gas coming out of a turn fast. Oversteer came easy on the Pilots too when applying full throttle in the turn. Not so with the G-force. It is very difficult to explain the way the G-force feels as it feels different than any other tire in existence. It just feels like the car is that much more “connected” to the road, and is probably a result of the triple or quadruple contact patch this tire provides. Taking a slalom turn quickly, the G-force was precise and not once did the ASC+T light come on. Nor did the car loose its tail, on repeated aggressive attempts. Remember, these tires still have only about 60 miles on them, so its still full tread depth. I assume they can only get better as the tread wears down a bit. Even applying full throttle around some turns, I heard screeches, yet the car did not oversteer. The tires (and now, the car) have that much more of a handling increase. It is going to take some getting used to and some risky maneuvers that I don’t recommend anybody try out on the street to reach the limit of this tire.

Rating for BFGoodrich G-Force T/A KD in Cornering Traction: 11/10 (it is just that much better than the others)

Rating for Michelin Pilot MXX3 in Cornering Traction: 9/10

Steering Response

The steering response of this tire is absolutely amazing. Not only does it provide more smooth transactions around turns, but it provides much more road feel in the steering wheel, and even in the gas pedal when you are using that to modulate around a turn. However, I think there comes a point where a tire for the street has too much steering response (I can’t believe I can say this). Maybe on the track it is OK, but for the street I think that BFG engineered too much steering response in this “street racing tire”. Wow? Too much steering response? It is so much more precise that the steering of the Z3 with this tire is a bit transformed. Moving it just a little bit gives the tire a bit of a “sway” feel that was not evident with the other tires. Perhaps it will take getting used, but I am not sure how I will appreciate this effect on long highway trips, as it requires more involvement in driving, which is fun of course when you are taking turns fast, but not when you are going down a straightway interstate. I will update this section as I see the long term effect of this to let you know how it is.

Long term update:

Maybe my initial complaint was valid but I think after breaking in the tire and letting the rubber settle down that my original comments are no longer valid. It does take some getting used to (as anything), but now I have learned to appreciate the tire and adjust my driving condition and style. Straight on steering feedback is definitely increased compared to the MXX3s, and straight line stability is awesome. Even after bringing the tires up to the 2.8L’s max of 128mph, the tires were well balanced, poised, and perfect. High speed is where this tire really shines, as at this speed the extra response does actually seem needed. I’d also like to add that the stability of these tires is amazing. I stayed at top speed for several minutes without stopping and the tires just loved it. Everything was smooth as butter and after getting out of the car and feeling the tires, they were just barely warm. I think that they dissipate heat a lot better than any other tire out there as well.

Rating for BFGoodrich G-Force T/A KD in Responsiveness: 10/10

Rating for Michelin Pilot MXX3 in Responsiveness: 8/10

Ride Quality

This tire is a bit weird in the way to describe the ride quality compared to the Michelin Pilots. While both harsh, as any 17″ performance tire is, this tire is a bit of an oxymoron. Over bumps, the tire transmits more of the bump to the driver, as you feel it in the steering wheel, and it is harsher then the Pilots. I want to attend this to the road feel this tire gives you over the others. But after staying in my car as a passenger, I haven’t noticed this, as the ride is actually better. What better place to test for bumps then an apartment complex full of speed bumps? That is where I did my comparison test. On the road, however, the BFG’s provide a smoother more buttery ride when you were NOT going over large bumps. I should emphasize large as if you are going on an interstate the slight bumps were absorbed better by the G-forces then the Pilots, but the Pilots took the speed bumps better. This category wasn’t really important to me in my tire buying decision, but hey I like the buttery feel better when highway driving.

Long term update:

The tires have changed a bit again after becoming broken in. The ride quality seems to be exactly the same as the MXX3, maybe slightly slightly better. Highway driving is superb, as is its ability to absorb bumps in heavy turns.

Rating for BFGoodrich G-Force T/A KD In Ride Quality: 7/10

Rating for Michelin Pilot MXX3 In Ride Quality: 6.5/10

Noise

This is wear this tire shines. In the dump, that is. This is the likely one of the nosiest tire I’ve ever heard. It’s loud and it’s noisy, and hey the engineers probably didn’t even pay attention, as that was not the design goal of this tire. Just put the top down (or for coupe owners) make the radio louder. The noise goes away.

Long term update:

Again the tires have changed after being broken in for several thousand miles. The noise is worse than the MXX3, but it is a different type of road noise than them. For example, on the highway with the MXX3 you would hear knocking as you kept moving at high speed. With the G-Forces, while being noisier, you don’t hear this knocking, but there is rather a high pitched noise. Such as when you are going over a bridge or such. I have gotten used to it and it is not that bad at all, not nearly asnoticeablee to me now as it was when I first got them. But all the extraadvantagess this tire gives is much more important then noise.

Rating for BFGoodrich G-Force T/A KD in Noise: 3/10

Rating for Michelin MXX3 Pilots: 5/10

Wear

Can’t answer this one, as the tires have only about 100 miles on them right now. However, as this tire does in most categories, I believe it will be excel above and beyond other tires, including the Michelin Pilots. I don’t like replacing my tires all so often, so perhaps these will give me 20,000 miles with a wear rating of 200, as the Pilots gave me 14,000 with a wear rating of 140.

Long term update after 3000 miles:

Wear is significantly better than the Michelin Pilot MXX3s were. There is just a hair of a bit ofnoticeablee wear on the rears. The fronts show absolutely no wear at all. I am definitely going to be pleased with this tire.

Rating for BFGoodrich G-Force T/A KD in Wear: 7/10

Rating for Michelin Pilot MXX3 in Wear: 5/10

Added Features

The G-forces have a rim protector that works very well. It is a big extra piece of rubber that goes around the edge of the rim, literally “hugging it”. This prevents the wheel from getting scuffed. I really hate to say it but I tested it once and it worked, I rubbed against the curb backing out and found no damage to the wheel.

Cost

These tires are expensive, yet not significantly more than other tires compared to it, especially given the increased ability that these tires give you. They are cheaper than the Pilots in the same size too, but not by much ($5/tire).

Long term update:

Tire Rack lowered the price a few dollars.

Rating for BFGoodrich G-Force T/A KD in Cost: 2/10

Rating for Michelin Pilot MMX3 in Cost: 2/10

Overall

Overall, I am quite pleased with my purchase and hope to have a fun time with my new “incredible” G-forces (as the ads go). After 3000 miles however I have noticed one thing. I am not understeering or oversteering anywhere NEARLY as much as I did. I actually miss sliding around the turns a bit as it is always fun to have the tail go out a little bit. But now I’ll admit I’ve only done it once, and since then (without changing my driving style on the street/highway) I haven’t done it at all because it just has such a high limit. It’s obvious that this tire is much more suited to the track then for the street.

Yokohama Nexus M Roadster Tires

After only 16,500 miles on the stock Dunlop SP8080 tires, it was already time to replace them. It was fun for awhile driving around Dallas with bald/slick tires. Very little effort was required to start the back end sliding out around turns (sometimes even when I wasn’t trying). But soon the fun wore off, and the realization that the M roadster wasn’t carrying a spare tire led to me finally accept that it was time to start the very “unfun” task of shopping for and purchasing new tires.

As I started my tire shopping research I found that the more I learned about tires the harder the purchasing decision became. To many options, to many variables and quite honestly to many opinions. To make the selection process easier I decided to start with the sizing advice posted on the Z3 tire FAQ. I then turned to the highly praised www.tirerack.com website, and decided to consider it the gospel source of tire information. There is always going to be differing opinions so I decided to put on blinders and just focus on what they recommended. Shopping for tires is both confusing and frustrating, I figured making this 1st decision would make the process easier.

2nd decision: I convinced myself that putting anything less than “maximum performance” tires on the M roadster defeats the purpose of purchasing an M roadster. So I click on the Tire Rack’s list of “maximum performance” tires and consider their recommendations as the initial candidate list. This narrowed to the field down to 7 tires

BFGoodrich g-Force T/A KD

Bridgestone Potenza S-02

Bridgestone Potenza S-02 Pole Position

Dunlop SP Sport 9000

Michelin MXX3 SX

Pirelli PZero System

Yokohama Nexus

Note: If you want to debate why one particular tire qualifies or doesn’t qualify as “maximum performance” take that debate up with the Tire Rack. Like I said I made the decision to follow this one particular website’s recommendations.

The first tire to be eliminated from the list was the Dunlop SP Sport 9000, for no better reason other than spite. I hate the Dunlop-sided SP8080E chunks of lopsided rubber provided with the stock M roadster. Besides being out of round I’m purchasing new tires after only 16,500 miles. I realize the stock setup used SP8080E and not these SP9000 tires but I will not even look at the Dunlop brand name (like I said, for no better reason other than spite).

For the remaining 6 tires I made the assumption that were all worthy candidates, but before I was ready to start comparing their individual merits I had one other requirement. I had made the decision to step up the tire size on both the front and back to protect the expensive rims on the M roadster. So the stock 225/45/17 on the front will become 235/45/17 and the stock 245/40/17 on the back will become 255/40/17.

Using some formulas posted on the www.tirerack.com web site I determine that going up one size will have the following affect: Fronts get .35″ taller and .39″ wider, rears get .31″ taller and .39″ wider. I realize that different manufactures have slightly different sizes but I’m going to ignore that fact and blindly continue on (remember this is already confusing and frustrating, why complicate things).

The wider tires will help protect the M rims (that are currently wider than the stock tires) and the taller tires will help make up some of the speedometer error (which is a poor excuse because I really don’t care about that). Now that I knew what tire sizes I wanted, two additional tire candidates were eliminated because they were not made in the sizes I wanted.

I was down to four candidates that matched my performance and size needs. It was finally time for the final showdown. I decide the wear rating (even though I realize makers rate their own tire) and price will determine the winner.

Bridgestone Potenza S-02 Pole Position – $964 [180AA]

Michelin MXX3 SX – $1010 [140AA]

Pirelli PZero System – $984 [140AA]

Yokohama Nexus – $490 [160AA]

Note: Prices are all four tires without shipping and were the Tire Rack’s posted prices as of February 18 1999.

What stood out from that list was that the Yokohama Nexus tires were about half the price of the other three candidates. My first reaction was “what’s wrong with them”, so I posted questions to the BMW roadster message board and call the Tire Rack directly. No one had anything bad to say about the Nexus tires and the Tire Rack said they are 99% as good as the Pole Position tires but at half the cost.

So that was it, the decision was made and the tires were ordered. Just under a week later the new tires were delivered and installed locally by National Tire and Battery. NTB charged $9.99 a tire for mounting and lifetime balancing making the total price of the four tires (with delivery, mounting, balancing and tax) $577.

100 Miles Later:

The traction appears to be superior to the stock Dunlop SP8080E tires. At this point the tires feel “stiffer”. Maybe that is what the experts call sidewall flex, I don’t know the technical term they just feel stiffer. The downside to this stiffer feeling is they are a little harsher in regard to ride comfort (CD Player is skipping a little more than it use too). The Nexus tires also appear to be noisier, I haven’t noticed it at highway speed but around town they seem a little noisier.

The pictures above and below show the front and back tires. In both cases I think the larger (than stock) width tires look better and more proper. The rubber is just slightly wider than the wheel surface and sidewalls appear to be straight up and down (instead of angled in like the stock tires). The tread pattern also looks sporty and just different enough to catch your eye.

So at this point I am very happy with my purchase, I feel like I got top notch tires at half the price. But this is just how I feel after 100 miles, I will add another update once I get a couple thousand miles on them.

16,500 Miles Later:

I’m mildly impressed with the wear I’m seeing after 16,500 miles. I have as many miles on these tires as the initial Dunlop 8080E tires. The Dunlops were nearly bald after 16,500 miles and the rear Nexus tires appear to have at least another 2,000 miles in them (the fronts a lot more).

On the negative side I’ve been caught by surprise a few times in the rain when the traction broke loose sooner than I expected it too. On one very scary occasion, there didn’t appear to be any standing water on the hiway but at 70mph I felt the car drift and noticed I was no longer in control. Ended up spinning and sliding onto the soft but flat shoulder. Luckly no damage, and no one else was around me when it happened but it could have been a bad accident.

I did pick up a nail during around 10,000 miles, a Z rated patch plug repaired the damage. While repairing the damage I had time to inspect the wheel wells and I did notice a tiny spot were the front tire had rubbed against the wheel well on each side. The spot was small and had not rubbed through the liner. I guess this tells me that the wheel did make contact with the liner but only a few times so it must have only happened a few times. When it comes time to replace these tires I’m not sure if I will stick with the 235 or go back to the 225 tires on the front. I know the 255 will remain my rear tire size.

The Tire Shell Game

“What tires come on the BMW Z3?” – At one time that was an easy question to answer. For all of 1996, the only tires you would find on a new BMW Z3 were Michelin Pilot HX MXM 225/50/16. In 1997, BMW released the 2.8 Z3 with an optional 17 inch tire package. The optional package featured an even better set of Michelin Pilot SX MXX3 tires. In 1998, with the introduction of the BMW M roadster, every review and advertisement showed the M roadster with the same upgraded Michelin Pilot SX MXX3 tires.

But when the M roadster was delivered to owners, the Michelin Pilot tires had been quietly switched to Dunlop SP8080E tires without any explanation or price change. The replacement Dunlop tires (including two of mine) had on occasion become “out of round”, which resulted in an annoying vibration right around 70MPH (+/- 5MPH). The Dunlop SP8080E tires quickly picked up the nick name Dun-lop-sided tires. However, BMW does not warranty the tires, Dunlop does. So those with bad tires were asked to find a Dunlop dealer and deal with them directly.

It appears the same shell game is being played with the new 2.3 Z3. I went to one dealership and the very first 2.3 Z3 I found had the typical Michelin Pilot HX MXM tires. But then every other 2.3 Z3 I found had Continental ContiSportContact tires. I am by no means a tire expert, so I decided to visit a popular internet mail-order tire shop and see what they had to say about all these various tires.

In comparing the Michelin Pilot HX MXM tires to the Continental ContiSportContact tires, I see that in the Tire Rack rates the Michelin tires a 8.7 and the Continental tires a 8.4 (pretty close). Looking at the price difference, the Michelin tires are regularly $178, on sale for $165. The Continental tires are regularly $145, on sale for $125. Some quick pounding on the calculator tells me that at the regular price that is a $132 total change and at the sale price it is a $160 change. It would appear that part of the equation used to keep the new 2.3 Z3 under the $30,000 MSRP was to use cheaper tires.

Using the same methods I turned my attention to the M roadster tire swap. The Tire Rack rates the Pilot SX tires at 9.0 but the Dunlop SP8080E tires are not reviewed. Using the Tire Rack’s search engine, I found the price on the SP8080E tires and discovered that the price difference for the four tires is only $2, so dollar-wise they seem to be equal counterparts. (Well, except for the fact that some of the Dunlop SP8080E tires are becoming out of round).

1.9 Z3 with standard 16″ Michelin HX tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

1.9 Z3 with rare1 16″ Michelin SX tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot SX MXX3 – $201

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot SX MXX3 – $201

2.3 Z3 with standard 16″ Continental tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Continental ContiSportContact – $145 ($125 on sale)

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Continental ContiSportContact – $145 ($125 on sale)

2.3 Z3 with rare2 16″ Michelin HX tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

2.8 Z3 with standard 16″ Michelin HX tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot HX MXM – $178 ($165 on sale)

2.8 Z3 with rare3 16″ Michelin SX tires

Front

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot SX MXX3 – $201

Rear

Wheels: 7Jx16 (46mm offset)

Tires: 225/50/16 Michelin Pilot SX MXX3 – $201

2.8 Z3 with optional 17″ Michelin SX tires

Front

Wheels: 7.5Jx17 (41mm offset)

Tires: 225/45/17 Michelin Pilot SX MXX3 – $234

Rear

Wheels: 8.5Jx17 (41mm offset)

Tires: 245/40/17 Michelin Pilot SX MXX3 – $261

M roadster with standard 17″ Dunlop tires

Front

Wheels: 7.5Jx17 (41mm offset)

Tires: 225/45/17 Dunlop SP Sport 8080E – $242

Rear

Wheels: 9Jx17 (8mm offset)

Tires: 245/40/17 Dunlop SP Sport 8080E – $252

M roadster with rare4 17″ Michelin SX tires

Front

Wheels: 7.5Jx17 (41mm offset)

Tires: 225/45/17 Michelin Pilot SX MXX3 – $234

Rear

Wheels: 9Jx17 (8mm offset)

Tires: 245/40/17 Michelin Pilot SX MXX3 – $261

(Note: prices are from www.tirerack.com as of 10/22/98)

1 Some 1996 1.9 owners reported receiving the better Michelin Pilot SX tires instead of the Michelin Pilot HX tires.

2 Michelin Pilot HX tires were on very early production versions of the 2.3 Z3. It now appears that every 2.3 is being delivered with the Continental tires.

3 Some 1997 2.8 owners reported receiving the better Michelin Pilot SX tires instead of the Michelin Pilot HX tires even though they were the standard 16″ tire size.

4 In the author’s opinion, this is false advertising, but in every magazine review/article/advertisement that I have seen, BMW used an M roadster with Michelin Pilot SX MXX3 tires. MZ3.Net is not aware of any M roadster owner in the US that has received the Michelin tires.

AC Schnitzer 17″ Wheels

Pros: Look awesome, increased handling
Cons: Cost
Cost: $1400

After 20,000 miles the original rear tires on the Z3 were nearly bald. The front tires were still in fairly good shape. I started shopping for tires (which isn’t much fun) but then I got lucky. Around the same time someone posted a set of AC Schnitzer 17″ wheels and almost new 235/40/ZR17 tires for sale. I had always loved the looks of the Schnitzer type II wheels and just couldn’t pass up the price this guy was offering.

A couple weeks later, four wheels and tires showed up on my doorstep. I put them on the Z3 that evening, the following day during my lunch hour I drove over to a tire shop and had them rebalanced (just to be safe).

Now my Z3 has always handled great, but the extra meat on these 17″ tires gives the Z3 even more stick on the turns. I can’t really tell a difference in ride quality, but my CD player has skipped a few times going over railroad tracks. I drove over these same track nearly every day and I don’t ever remember the CD skipping with the 16″ wheels. I’m only bring this up because I can’t “feel” a difference in ride comfort, but obviously my CD player does.

Another benefit is that the Z3 seems a little more sure footed on high speed turns. There are some pretty good off-ramps here in Dallas. Occasionally the Z3 felt a little figity on high speed turns with the 16″ tires. It must be the wider footprint of the 17″ tires that made the difference.

All four of these wheels are 17″ by 8.5″, stock the 1.9 came with 16″ by 7.5″. The bigger and wider tires fit just fine in the Z3 wheel wells. I have not had any tire rub, and there is still enough extra clearance that I’m not worried about it at all. The wider front tires have made the steering wheel fell a little heavier, just enough to notice.