Sneaky Pete

I have the Pilot Super Sports 235's in front with 295/35 on the rear. Not that big of a difference in diameter. You would love these.

mklein9

Whoa Pete, compared to 285/30 that is a 36.5 mm increase in diameter, or 6%! That seems awfully big, no?

Sneaky Pete

Wups .....that was a typo......the super sports don't even come in that size. I have 235/40 front (25.5" dia) and 285/35 rear (25.9" dia). That is .4" off difference front to rear or 10 to 11 mm. Now what are you using mm for? I had to take my shoes off to do the conversion.

perryinva

I did all new N3 PS2s about 10 months ago. Love them. About $1400 out the door, mounted, balanced, road hazard and N2 fill from Costco. No one could touch their prices, mounted and balanced, and at my local one, the head mechanic drives a 996, and treated my car like gold. Even made sure he aligned the center caps so the pointed part of the crest pointed at the valves. THAT said, I wouldn't hesitate to go Super Sports in the closest matching size like Pete did, and likely will on the next set, as I doubt even the PS2s will even be available then. I get 4-5 years out of my tires on the 996, as I only drive around 4k a year. Drove an M3 with them on, and was impressed.

mklein9

Pete, OK that's a lot closer. Also with the current $70 rebate on a set of Michelins a full new set of SS's cost just a few dollars more than two PS2 rears.

HOWEVER -- My mechanic says he has had significant problems getting the ABS to function correctly when tire sizes are different from the recommended/approved sizes. They've even had problems when they are the correct sizes but for example the fronts have lots of tread and the rears and worn.

I assume your car has ABS; PSM by any chance? Have you had any issues with the ABS?

Sneaky Pete

My C4 has both ABS and PSM. Both systems work just fine. At the current price point for the super sports I would by the new set.

mklein9

Super Sports are also available in 225/45-18. Going through the tire detail info at michelinman.com the 225/45-18 and 285/35-18 are both 25.9". Any chance that might work? Having the same widths as original could also be good.

With the X74 is there enough room in the front to increase the radius by 0.4"? I looked at mine with the existing 225/40-18 Sports on the front and there is maybe 0.7 - 0.8" clearance between the tire's edge and the strut flange. That's maybe good enough, not sure; what happens when cornering and camber goes maximum negative?

Another benefit is the 3.2% increase in diameter will make the speedo closer to correct. (Which BTW I've found as others somewhere have mentioned has a constant 4 MPH bias up at all speeds above about 25 mph.)

Sneaky Pete

If you think about it the .4" is the diameter the radius is half of that or .2". I think you are fine. Below is a pic of last year. The left front is stuffed up there pretty good but still has room with no rubbing.

mklein9

Pete, nice pic!

The diameter of 225/45-18 is 25.9" and 225/40-18 is 25.1", so diameter increase over stock is 0.8" and radius difference 0.4". You might be comparing against 235/40-18 that you are running? Could you handle an additional 0.5" diameter over yours? That's what 225/45-18 would be. The benefit of this size is SS's and no difference in front/rear diameters.

Sneaky Pete

Yes Mike I was referring to 235's. I think the sizes you are thinking about would be ok fit. I was going for the wider tire without getting too tall.