Backstory:
I just picked up a brand new set of tires mounted on 16x6.5 AK Monza wheels from someone who intended to run them in G-stock. They seem kind of small compared to my RT-215 in 215/45/16 im running now.

Am I concerned with the gearing probably more than the lateral grip? They are 22.5" as opposed to 23.5" for the 215/45's. I give up about 3/4" in tread width and 4/10ths" compared to the 205/50/15.

I'm trying to decide weather or not to sell them and get 'Kooks or Kumhos in a larger size. I love my old Azenis and I wouldn't have ordered these, but I got the whole wheel/tire package for $50 less than the price of just the tires unmounted .

I plan to only run a few CENDIV events and mostly regionals.

Anyone try running these yet in GS or STX? Use for rain tires?

 

I've been running them for a month (street only so far, no Autox or HPDE yet) and they are phenomenal! The smaller diameter really wakes up the tall first gear and gets the rest of the gears pretty close to the '05 MCS. I compared GPS readings to indicated speed and recorded an 11% difference at most speeds, so an indicated 77.7 mph = a real 70 mph. They grip at least as well as the RT-215's in 215/45-16 I had before, and the turn-in is much sharper (probably due to the lower sidewalls). At $84 per tire, I can't complain at all.

 

I've had mine on the car for less than a month - 205/40/16 - I agree with Andy that the speedometer error is there due to the smaller diameter. It's obvious when you hook up the GPS or when you try to figure out why every one is passing you when you think you are doing 75.

The other advantage to the 205/40/16 size is that with my 16x7 SSR comps each wheel and tire only weigh 29 lbs.

However, I have autocrossed on them once (STX) and found them to be louder and not quite as sticky as the 215 version or apparently the new Hankook rs212. Maybe they need to be scrubbed in some more or for the true fanatics shaved for better grip.

Last autocross I ran in DSP on Kumho 710's and was amazed at the grip from the r compounds.

David

 

These were the first tires we ran on our STX car ('05 Cooper S). The gearing we gained was impressive, but not enough to overcome the lack of treadwidth. Even with limited slip, we were having a lot of wheelspin issues. After going back to RT-215's the car seemed more "driveable". The smaller RT-615's do kick but in the rain! Next we will try the 225/45-16 Hankook's, hope they're not too big.

 

Thanks for the feedback. Sounds like it is worth some testing to figure out how to best use these tires. We run mostly short technical courses in our region (Tire Rack Test Facility) which may help. I will probably use the taller 215/45/16 RT-215 at Grissom and Toledo so I can stay out of 3rd gear on the longer courses.

 

Hi Guys,
I just got my '05 MCSa, and am looking for help with tire selection. The auto's gearing is even lower than the revised gearing of the standard MCS. I would like to start in GS, but don't want to run the R compounds, and I need something that will work in the wet. Any suggestions as to tire size & model? I have a set of X-lites that I plan on using for this rubber.

Thanks,
Jim

 

Hankooks R-s2 z212 in a 225/45/16 are the hot setup according to Andy Basham (BMW 330i) who smoked everyone in STX in the rain at Toledo this past year. He ran shaved Hankook's in the dry with sucess at CENDIV events also. He happens to be a quick driver as well.

Run them full depth for rain. Gosh, they are even cheap!!!!
Link Here: http://www.edgeracing.com/cmdhankook

 

Thanks Minifinn,
Interesing looking tire. Any thoughts on if staying closer to the stock diameter is better for the MCSa gearbox, or if going lower, like 40 series would be a better choice. The autos 1st gear is lower than the standard (14.89 vs 11.4 for up to the '05, 2nd 8.73 vs 7.18). Is that going to be too much of a gearing change? Maybe Andy could venture an opinion there? Would the really small diameter tire be a bigger plus for drag racing?

Thanks,
Jim