Not sure if it's just me adjusting to the MCS' new tires, but I'm currently under the impression that I made a $600 mistake...

Long story short, one of my old Eagle F1's was badly flat-spotted from an autoX spin, and Goodyear no longer makes the F1 D3 in 205/50-16 > total replacement. I wasn't overly pleased with the selection / pricing of tires in the 205/50-16 size, so I upped the section width to 225 and pulled the trigger on a nice set of Conti's. At the time, I figured the additional overall height would knock down my revs a bit give me a (much needed) boost in MPG. Fast forward to this afternoon, after getting the new tires on the car: The additional sidewall has REALLY degraded steering response (my winters are almost better), and I think the additional overall height has actually hurt my mileage since I have to open the throttle harder / longer to change speed (just averaged 22 mpg on a short highway stint where I'd normally get 28-30)

Opinions? The tires themselves are nice, I just think I got the size wrong. I don't think I can live with the steering response as flaccid as it is now, and I definitely can't live with 22mpg highway... I can probably ditch them for close to what I paid, but I don't want to jump the gun either since I'll have to pay to get the new ones mounted / balanced, etc - ya know?

 

checked/upp'ed the air pressure? Might help with both your reported ill's--MPG's and road feel.

Remember, as you increase the diameter, your speedo and odo gauge readings are a bit different too (and typically w/ less observed error on the speedo relative to actual speed per GPS). Do the math, but that may be 2 or 3% that you won't see by tracking miles from the odometer (it will see that percentage fewer now), but they are miles your car is in fact covering. In other words, also adjust your "before" and "after" MPG calc's by that % if the odometer was where you calculated the miles from.

 

Z06, which conti tires did you get?

 

Set the pressures where I normally run for the street (~35). I was trying to figure out how the additional diameter would effect the OBC / mpg, but my brain was too pre-occupied with agitation over how much slop is in the steering at speed.

Slinger, they're the Extreme-Contact DW's. The real kicker is that that tire is actually available in 205/50-16 as well - but I happened to be talking about another 225-width tire with the sales rep at the time, so we carried over the size. And to further spite me, I see that Dunlop is now offering an $80 rebate on the Star-Spec's I originally wanted but avoided due to the cost. Grrr.

 

I can't help but say that if I don't run 38 lbs on my tires I don't like them. You might want to give it a shot.

 

I am on my second set of Nitto Neo Gens in 205/50/16 an all around freaking awesome tire. Running on a set of 7 inch wide Enkei with a 38 et. This combination provides the best response and go-kart feel of any set up I have run. And due to the tread design it loves the MINI's natural offset of the rear suspension. With that et of the rim, they are a perfect match for the 1st Gen Mini. And they can be had for around 80.00 per tire most places.....

 

I don't think it's just your imagination, and I think your causal analysis is correct. My guess is that you'd be much happier with the same tire (which gets very good reviews here and elsewhere) in size 205/50/16 on the OE 16" rims. I think the 225/50/16 is just a bit too wide and too tall to deliver the steering precision and cornering feel that a 205/50 would.

The 225 is about 20 mm wider than the 205 and is molded to optimally fit a 7" wide rim, while the 205 was molded to optimally fit a 6.5" rim. Some steering precision might be lost there.

Second, the 225/50 tire is about .9" "taller" (larger in diameter) than the 205/50. That would be about .45" more sidewall all the way around the tire. That should produce more sidewall flex when cornering.

Third, the bigger tire weighs a bit more as well, so it should take a bit more to get it up to speed, and a bit more brake to get it stopped.

None of these are huge differences, but in combination they are probably enough to produce what you experienced.

You probably already know this, but new tires won't provide their optimum grip for the first 100 miles or so of driving. In some cases it may take 150 miles to wear off the mold-release fluid from the outer tread surfaces.

That's just my opinion. Check with others. I don't want to be the only one to blame if you switch to 205/50s and say the tires still suck.

 

I'm on aftermarket 7" wheels, so 225 looked even more appealing over 205 based on optimal rim width. I think what I'd really like is a 225/45-16, but it seems no one makes a good max / extreme summer tire in that size.

Indicated mileage actually dropped with more driving this afternoon (mostly highway, again), so these suckers are coming off first thing next week. Shoulda just bucked up and got the Star-Specs like I wanted to all along...

 

I see your problem there...you got some of them fancy 7 inch rims with 225 aspect tires. They must look PHAT. I think they will throw off you MPH reading though.

 

I'm running 205/50/16 Starspecs and love the feeling of them. They seem to be wider than the oem 205/45/17's that some S models at the dealer had. So wide that I don't think I could fit 225 starspecs on the back without rubbing over big bumps - and tire rack told me 225s would rub.