Alternative Tire Sizes for Your MR2 Spyder

Thursday, December 29, 2011 by Cy Chowattukunnel
With approximately 500 tire models and 17 different manufacturers to choose from, you would think that every driver would have many choices when selecting their next set of tires from us; however that's not always the case. 

The Toyota MR2 Spyder is one of those hard-to-fit vehicles. 2000-2002 MR2 Spyders (we'll call these early Spyders) ran O.E. 185/55-15 tires on the front and 205/50-15 tires on the rear, while the 2003-2005 MR2 Spyder (the later Spyder) ran the same front size but had 215/45-16 rear tires.

When searching for alternative sizes, we need to consider the following before coming to a final decision: overall tire diameter, oversteer vs. understeer balance, rim width, potential effect on anti-lock brakes, tire clearance and availability.

Overall Tire Diameter

To ensure that the vehicle's center of gravity remains the same while maintaining Original Equipment gearing and an accurate speedometer, we need to stay close to the O.E. tire diameters: 185/55-15 at 23.0 inches, 205/50-15 at 23.1 inches and 215/45-16 at 23.6 inches.

Oversteer vs. Understeer Balance

Every car has a tendency to understeer or oversteer at its limit (or in an emergency evasive maneuver). When the front tires lose grip the car understeers or "pushes" through a turn instead of following the line of the turn. Or the rear tires may lose grip, causing the vehicle to oversteer or "fishtail." To learn more about understeer and oversteer, read "Winter Driving Tips."

When changing the size of tires, it's important to maintain the O.E. balance or only slightly tweak to fit preferences. If you change to a wider size in the rear without a corresponding change in the front, the vehicle will have more understeering bias relative to the Original Equipment set-up. Doing the opposite will move the vehicle towards an oversteer bias.

Rim Width

Both early and later Spyders ran 6" wide wheels in the front (referred to as 15x6) and 15x6.5 in the rear. Later MR2 Spyders used the same front size and 16x6.5 on the rear. 

Tires have enough bead and sidewall flexibility to allow the same rim width to accommodate a variety of tire widths. All other things being equal, wider tires on the same rim width diminish steering response but help protect the rim from curb scratches.

ABS

Vehicles equipped with ABS work by looking at the differences in rotational speed. Therefore, avoid a major change in the difference between the front tire diameter and the rear tire diameter compared to O.E. set-up. The car may think the taller tire (which is rotating slower) is slipping and therefore the ABS brakes may not work properly. There's no exact percentage difference to stay within, but our experience suggests that you want to be within three percent of the Original Equipment. 

Tire Clearance

We need to make sure the tire clears the fender, the wheel well and the suspension. We're very conservative when we look at the risk of rubbing. 

Tire Availability

When looking for tires that fit a staggered (wider in the back) set-up, shop for tires by size.

Early (2000-2002) MR2 Spyder Tire Sizes

Some Spyders came with Yokohamas as Original Equipment while others were equipped with Bridgestones. The Yokohamas have been discontinued and are unavailable but you can still purchase the O.E. Bridgestones.

195/50-15 (22.7" diameter) front and 205/50-15 rears maintain the overall diameter, fit the O.E. rims, preserve the vehicle's handling balance, don't rub and offer more choices.  

Later (2003-2005) MR2 Spyder Ti
re Sizes

You can still purchase the O.E. Bridgestone Pontenza RE-040 in 185/55-15 fronts (23.0") and 215/45-16 rears (23.6"). The rears are W-speed rated and the fronts are V-speed rated, so these tires won't appear in a matching pair search even though they're the Original Equipment tires.

Alternative tandem sizes include 195/50-15 fronts (22.7") and 205/45-16  rears (23.3") and 195/55-15 fronts (23.4" ) and 205/45-6 rears (23.3").

Which Tire Do I Recommend?

The optimum choice depends on what's best to balance steering response, ride, wear, oversteer/understeer bias and budget. However, if I had a late model MR2 Spyder as my fast summer car, I'd select the Bridgestone Potenza RE-11 with 195/50-15 on the fronts and 205/45-16 on the rear.

Comments on Alternative Tire Sizes for Your MR2 Spyder

Leave a comment





Captcha