I switched my car back to the original configuration including Fuchs (it had turbo twists) and I felt it was a little quicker etc. but I agree it seems very similar. The biggest challenge in the future is tire availability in the original tire sizes in the 16 inch spec.
Was considering increasing front size to 225/50/16 from stock size of 205/55/16.
My biggest concern is would it make front steering heavier? I tend to stay away from larger diameter and tires for porsches to keep that light front end steering feel.
With 225 will it understeer more?
Will stick with 245/45/16 for rear.
225 puts more rubber on road than 205 and with a lower aspect ratio, both these considerations will give you less understeer. You get better turn in + quicker response to all inputs - including improved braking. I believe you will notice a difference in a parking lot, but not while street driving until you get close to the hard cornering limits (i.e. high speed on/off ramps).
IMHO the skinny & tall 205/55 is a poor compromise but safer from a factory/OEM liability viewpoint since they fear oversteer so much.
Further humble opinion: every 911/930 should have adjustable sway bars installed to fine tune F/R balance.
I had the larger size on my 930 when I bought it and went back to the factory size when I needed new tires. Frankly, the difference in size in minimal: maybe .5 to .7 inches wider with the same exact diameter. So while it is a little wider it does NOT have a shorter sidwall and probably for this reason not a noticable difference in performance. What I would recommend, is going with a "ultra high performance summer tire" since not many of us drive our cars in winter anyway. I like the Bridgestone Potenza's that I bought for the Porsche but the Sumitomo HTRZ's that I put on my 03 Mach 1 squeel like a pig and seem a little greesy compared to the bridgestones or the BF goodrich KD's that I used to have. Also, the 225/50's look a little too big on the original Fuch's, not a fitment issue, just aesthetics. Use the Tire Rack to compare, thats how I came up with the Bridgestones.
The issue does not seem to be the availability of front tires in 205/55/16 or 225/50/16 sizes as there are numerous options, it seems to be the availability of rear 245/45/16's. In a quick search of Tire Rack the only "street" tires shown are Fuzion and Conti's. Any other matched sets currently available (I do not like running different tread patterns /compound front and rear)? Is there a different size option for the rears? What are people currently doing (I want to keep the original Fuchs)? The car is a street only car.
I've used both 205/55-16 and 225/50-16 on my fuchs and noticed very little difference. I prefer the way the 205 tire looks on the stock rim. The 225's sidewalls bulge out and do not look right. My tire of choice for the street in this ever decreasing rim size is the Toyo T1R.