About to buy a set from a 6speed member ... but before purchase .. anyone running these measurements on an AWD 997 TT ? are the circumferences close enough NOT to have an issue ?

hovering about 3%

Tires:
Fronts are 245-35-19 ZR Toyo R888
Rears are 325-30-19 ZR Toyo R888

I am running 11.5" advan rzdfs in rear and 8.5" in front..
THX

 

I run same set up with no issues 325 and 245 on 12 and 8.75 inch rims.

 

The circumference based on the sizes you mention should be fine, however, you need to double check the circumference after mounting the tires as the wheel sizes may squish the tires a bit and they may bulge in the center or around the outside, so measure on the outside of the tire, center and the inner.

At one point I tried a 265 front tire, and it should have worked out, but the center of the tire had a circumference of 1/4 inches out of spec and that caused havoc on the electronics and the PTM.

Having said that, I would not sweat it, mount and measure twice and go for a short drive and see if the you feel any oddities in the drivetrain. In my case under deceleration (in particular when I would just lift from the accelerator, you could feel the PTM and traction control kicking in as measurements where going out of spec and the car would either think the fronts have lost traction or the rear. It was interesting when it would think that the right front (for example) had lost traction. The car basically then rotates on one of the front tires.

Let us know how you make out.

Cheers.

 

Dude i've been running that set up for over a year now with no problems with Mpsc & 12" & 8.5 on my ADV.1 & now with the Toyo's R888 on my Dymags at 12' & 9" but according to our friend yellow turbo you gotta keep them real low on the psi like 22 f 24 r cold.

 

i just mounted them .. feels a bit taller than the mspc s but i will do more test runs after i get an alignment ... west end has me on waiting list ... BOO .. other wise nothing till tuesday.. no event ...

I am actually hoping not to make i to the SS event as my car is going NUTS.. pulls to the left like crazy then feels like it is spinning tires on 4th and 5th gear ?.. got new tires to eliminate that ... had a broken drop link ..put that in today as well .. lastly will try alignment ???

Could it be OEM LSD failing ? one side pulls more than the other when "pushed"