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Hi, I have 275/35-19 up front (Bridgestone S04). It fits fine, but did complicate the installation of brake cooling ducts. Had to install a short section of hard pipe of a smaller diameter to clear the tire when hard over.
Great on the track, getting me convinced to go four square in the future (with better rubber), No understeer and tail comes out nicely under late breaking. Did notice was working the brakes harder with the bigger front tire!! I have -1.5 camber so it fits under the wheel well with room to spare.
Street ride is harder but going to a 2 setting fixes that. I used a 3 on the street before with OEM tires sizes. With 5 had no issues on the track (4 in the rear to help keep the tail in tow).
You can look up detailed tire specs on Tirerack.com. A 275/35-19 is essentially the same (very close) diameter as the stock 255/40-19 and 295/35-19 Pirellis, and should fit no problem.
You'll want to make sure your wheel offset is +35 to +45 ET (or so)... anything much less than +35 ET and they'll stick out of the wheel wells. Much more than +45 and you may have front strut clearance issues.
FWIW, I'm running 295/40-18 Hoosiers (big MF-ing tires... 27.3" dia) as my track tires on all four corners on 18x10 +42 ET wheels, with -2.5 deg camber, and they fit with no issues except for an occasional slight rubbing on the right side brake duct at full steering lock when stationary or at parking lot speed. (Should also mention that I did have to cut off the excess upper sway bar stud to avoid contact with the inside sidewall. With 275s you should be okay, though.)
I like it...a lot...its the full KB set up:
- KB/Eibach Coil Over struts/shocks/springs
- MM Caster Camber Plates
- MM Bump Steer Kit
- ARP Studs
- Front Lower Control Arms
- Eibach 36mm 3-way adjustable sway bar (front) w/ Steeda Adjustable End Links
- Rear Lower Control Arms (Street/Sport) and Relocation Brackets
- Upper Control Module (3d Link)
- Rear Roll Center Relocation Kit (no rear sway bar)
- Jacking Rails
- Matrix Brace
- Rear Shock Tower Brace
Other mods include
- 14' slotted, 2-piece Baer rotors (front and rear)
- Stop Tech SS brake lines w/ MOTUL RBF-600 brake fluid
- 12qt Chicane23/Armando Road Race Oil Pan
- DSS 1-piece Aluminum Driveshaft
- Hurst Shifter w/ Barton Bracket
- Kooks Shorty Headers
- GT-500 Axle Back w/ 1 1/8" exhaust discs
- GT-500 fan assy
- Boss 302S Grill
The KB K-Member increases the front caster such that a 265-40/19 and certainly a 275-40/19 tire will rub on the inner fender. I am running a MM 1/2 spacer on the front to move the front tires back out to the fender lip...this might also resolve the clearance issue you mention with the brake cooling duct as well.
All in all, I am very pleased with how it handles and rides on the street...hope to get to the track soon.