Danyol

Thanks guys!
I'll pull off a wheel and check width and offset.

Looking at Tire Rack for the 315's It's Conti (II & Vmax), PS2 and Yoko Advans. What would you install on a daily driver with occasional track use?

wross996tt

Yokos by far....I have them myself.

Land Jet

PS2's are my choice and are designated Porsche tires.. Stay away from P-Zeros in any case. Known tire cord shifting problems.

Danyol

OK Guys, I pulled the wheels off.

The Stampings on the Inside of the wheel are "Champion 19 x 115 44" & A9115R44"

I presume this means 11.5 wide and 44mm offset?

Superfly

That's how i'd read em. Compare them now using that offset calculator I posted earlier. Stockers are 11 wide and 45mm offset. (so your Champion wheels are 5mm less on the inside and 7mm further out on the outside). I'll bet they look really good in person!

Duane993

Those shouldn't rub. You could try a 5mm spacer on the back wheels to push them out, but you'll have to roll the fender lip. I've got no rubbing with 1" drop and 11.5 x 19 E39 315x25x19 rears

D_Nyholm

I've got the same setup on my TT, but I have PSS10's dropped a decent amount (25.25" from floor to bottom of fender measured through the middle of the wheel) and I get rubbing with 2 people in the car in the rear (400-450 lbs total extra weight). I couldn't imagine going to 315's and not have them rub!! I am thinking i need to roll my fenders with it like this and definately if I go to 315's when these wear out. I haven't looked yet whether or not they are rubbing on the inside or the outside.

Let me know how it goes with the 315's and what you had to do re: rubbing.

Danyol

I installed 315/25-19 on the rear, no rubbing whatsoever; much more clearance than the 295/30-19 that was installed before. In diameter they were a better match for the 235/35-19 on the front.

Sacrilege! I didn't go for the high end tires (PS2, YOKO), I'm trying 2 TOYO T1Rs for the price of a PS2. Much better traction in the rear wet or dry than the Pzero.
The Pirellis are still in the front, looks like they'll last forever (anyone need some partially worn 235/35-19 rossos?). The PSM will kick in and cause the car to "push" in the front on hard cornering, I'm guessing it's the difference in compounds.

Anyone have any thoughts on this; do I need to bite the bullet and replace 2 unworn tires?

D_Nyholm

Good to know Danyol!
I think i'll go for that size on my next set of tires. I went out last night with a GPS and noticed that my speedo is reading high about 2 mph at 60 (295-30-19)so these should make it read low. They seem to be about 1" smaller though, how off is your speedo?

wross996tt

Yeah, you really got a deal...buy 2 for one and have to replace 2 others

Danyol

Hey, I didn't want to buy P-zeros for the worn rears so I think I was already down the path.

God you've been a little more testy recently than usual!

Danyol

D, the diameter is a definitely smaller but compared to the local police radar speed display my speedo still over reads (32 in a 30). I'll check at speed on the GPS next time I have it in the car.

wross996tt

You just need to understand my humor....as I see it, you ask for advice on what tires to buy...you ignore the advice and tell us what a great deal you got (like those of us who have bought the PS2s or Yokos have been screwed). Now you post you are having PSM problems as a result of your most excellent purchase....hmmm.

In any case, the PSM coming on is more likely due to a mis-match in OD than in compounds. Good luck

Danyol

Statman, I read and appreciate your posts here and over at 6speed; usually find them very informative. I agree its very easy to misunderstand a person's intent in written form without knowing them more personally. This is compounded by the fact that I'm originally a Brit with the cultural distance too

The original intent of my thread, when I first picked up my car, was to learn about the sizing of tire and lowering options. I've made some better educated moves here to the larger tires and the next purchase will be the PSS9's (if the Bloo.y stock market will assist!). I understand the compromises involved and checked on the manufacturer's diam spec for all the different tire options. This spilled over into the best choices in tires.

In all the research I've made the top choice for these cars for the street would be the Yokos or PS2. My personal use of the car is as a daily driver (and yearly replacement of tires) I felt maybe if I give up 10/10s of tire performance perhaps I could find another compromise for me. After some very positive posts elsewhere I felt it was worth trying the T1R as a good compromise. It didn't seem to be a big risk in $ either if I had to back out.

The diameter from Manufacturer on the 315/25-19 Toyo is 25.2" and the 235/35 Pzero on the FR 25.5" (the original 295-30-19's on my car were 26.1"). Now, being that the front Pzero is also partially worn it should be pretty close. I've since lowered the FR pressure to 34psi (42 rear) and the PSM hardly comes on now, except in v. hard cornering over bumps in the road.

Land Jet

Statman, my 295/30 18's are rubbing the wheel wells in the rear. With stock wheels and offsets, 50 fronts, 45 rears, how will I be able to fit 315's back there? Will I need spacers?