Bridge 03 vs Kumho MX

A number of 328 owners have gone up to 225/50-16 front , 245/45-16 rear on the stock 16x7f/16x8r rims.

If your main concern is adjusting your handling balance, you can accomplish some of that without having to shift "ballast" (e.g. aircon).

To reduce understeer, you can increase front tire pressure, lower rear tire pressure, increase negative front camber, decrease negative rear camber, soften the front springs, harden the rear springs, shift to a thicker front or thinner rear anti-roll bar, or - as you say - shift weight distribution rearward. (The opposite adjustments decrease oversteer).

I've found that just tweaking front/rear tire pressures by a couple of psi produces a noticable result on my 328. (Once it was aligned.)

While these things will increase your limits, I don't know of a way to give you more warning about approaching the limits on a mid-engine car ... other than getting noisier tires, so you can hear the shift in the road noise as you increase load.

If wet handling isn't a factor, you might want to look into Yoko A032Rs in the hard compound as a "middle ground" between tires like the S03 and full comp tires. But if your 308 is your daily driver, you'll likely wear out A032Rs (rather than have them age out, like tires on occassional use cars). But they certainly qualify as "noisy".

 

I actually noticed the S03s tossing quite a bit of klag against the wheel wells, when I switched from the old GY VRs -- probably because the VRs didn't hardly have any tread left. With all the road construction in MA, there's tons of little "cold patch" pebbles around, and the deeper tread blocks pick those up with alacrity. In traffic, I'm usually more concerned with the stuff tossed out by the tires on the truck in front of me.

But if you're worried about FOD from your own tires, that would be a strike against going to a +1 size. The Goodyear F1 GS-D3s have gotten good reviews (but they came out just after I put S03s on my 328). As far as I can tell, the F1s aren't available in the +1 245/45-16 size, though, so that's only an option if you stay with the stock sizes.

I've been impressed by the A046Rs that came with the EVO, but they're only available in limited sizes, and they're not all that great in the wet. I think I now have the tires the wrong way around. The S03s would be better on the EVO, with the stickier dry-oriented Yokos on the 328. Ah, well.

 

All correct, except for the anti-roll bars: A stiffer rear bar will keep the inner curve front wheel better to the ground, reducing understeer.

With my 308 I had succes reducing understeer by giving the front wheels a fair amount of neg camber, and using wheelspacers, 25mm front and 12mm rear. Looks also a lot better!

 

over on the BMW board, the consensus is that the MX is as good as the SO3 as far as grip is concerned and with the added benefit of lighter (the Toyo T1S is another "light" tire) even a better deal.

Another tire that is not R compound, not too friendly on the wet, but extremely sticky is the Falken Azenis tires. Not sure about the weight of them, nor the size available, but many people swear by them and apparently the current rage among autocross. Again, its not a R compound tire, but very close.

 

Since I currently own a BMW M Coupe, this is where I hang out most of the time: http://bimmer.roadfly.org/bmw/forums/z3-coupe/

Search on Azenis and MX on the Roadfly website and you will see tons of responses, particularly on the Z3 Coupe board. I too live for the turns and with as lively car as I have, its always entertaining to say the least. Let us know what you get and your impressions too.

 

Stephen:

Too late as you already ordered the tires. I would have to say there is no way you can compare the Kumho 712 with the S-03s. The S-03 is one of the best handling tires out on the market. It wears fast due to the sticky compound but it is amzing in the wet and dry and is very progressive at the limit (unlike the 712 which just lets go with no audible warning). I would have to say the S-03 and Michelin Pilot Sport 2 are your best bet, but please let us know how you make out witht he Yoko.

 

Where wet handling is a factor, I'd also recommend the S03s -- I put S03s on my 328 when it was my daily driver.

But I've also had some time with Yoko A046s. (I mis-spoke, above. The A046 isn't technically an "R" compound, although the wear and handling is similar to the A032R reviews.) I've also seen the difference in the EVO between the Yokos and the Nokian WR winter tires. A tire that can make this huge 4-door EVO handle like the Ferrari is none too shabby.

The S03's go noticably "off" below 40F, but the Yokos go away almost completely in the cold. (You can warm them up with a bit of jinking, but nobody runs them in the snow -- past one or two corners, at least.) While I'm not impressed with the wet handling of the Yokos, compared to S03s, I've noticed that the reviews rate the A032Rs as great in the wet ... compared to other "R" compounds.

My conclusions are that the S03 is a good daily wet and dry tire. The Yokos are extreme beasts for occasional use, where wet handling and noise aren't factors. Which is why it's ironic that I now have S03s on the Ferrari, but Yokos on the daily EVO.

Stephen, you might want to look into heat cycling your A032Rs (or get the heat cycled ones), as that is said to improve the life span. (We haven't done a "heat cycle" survey on the A046s, but EVO owners are getting wide variations in tire life on those, too. But then, the early life of A046s so far are wrapped up with the break-in period of the cars.)