NightmareMoon
Well-Known Member
Keep in mind factory setups will nearly always be tuned to understeer at the limit. Its just safer for 98% of drivers. That's one reason why the PP1, PP2, and GT350 wheels are 1/2" staggered. These are mass market cars, driven by all sorts of unskilled drivers.
Fit also is a big factor. Its really easy to fit 11s in the rear, but 10" is the widest no-brainer fitment in the front. So the "easy" wide tire fitment for our cars ends up being a staggered fitment with 10F and 11R. Requires no work besides swapping wheels, and gets you a wider-than-stock tire at all four corners. Its win-win for most drivers, even if the handling balance is significantly weighted towards understeer at the limit.
However, square setups are proven to be a more efficient way to get around a road course. A good driver on a 10/11' staggered setup wouldn't be much faster (if at all) than a good driver on a 10/10" setup, and the square setup driver would be spending less money replacing tires, since they can rotate them to even out wear. At the cornering limits, you're somewhat limited by the lesser of the two axles. If the front of the car won't turn then the car won't turn, so having a wide 11" rear tire won't help if your anemic front tires can't get the front turned too.
Wide front tires help you get down to the apex quickly. Wide rear tires help you get away and accelerate out past the apex. A track car needs both, but your average street driver generally cares more about straight line acceleration and won't be testing the very scary limits of cornering while trail braking or balancing a car with throttle at an excess of 1.1Gs that the stock PP1 cars are easily capable of.
Ideally you're running a squared setup that is ALSO very wide. That's why people go to extended front studs with slip on spacers to run square 11/11" setups (or the factory Ford 10.5"/11" combo, which is pretty close). Fitting an 11' front is a tight fit. It requires a mix of camber AND just the right wheel offset with little margin for error (~5mm or less at the strut).
The 10.5" PP2 front wheel (and remember the PP2 is a very rare, unusual factory option) pinches the 305 tire down to a slightly narrower size, which allows conservative factory strut clearance, and stock GT fenders without changing the normal stock GT camber configuration. For a track car, a square 11" setup is more economical, and we assume that track car will be fine with less strut clearance (roughly 0.4" less) than Ford Co. will be ok putting on a factory car and will probably be running more than stock camber. As per Ford, the PP2 isn't optimized for the track. It needs coolers, and also, it really needs a bit more front camber.
Porsches and other cars are different. They'll have different power levels, different weight balance, and different suspension geometries. For some of these cars a staggered setup will be faster around a road course.
Fit also is a big factor. Its really easy to fit 11s in the rear, but 10" is the widest no-brainer fitment in the front. So the "easy" wide tire fitment for our cars ends up being a staggered fitment with 10F and 11R. Requires no work besides swapping wheels, and gets you a wider-than-stock tire at all four corners. Its win-win for most drivers, even if the handling balance is significantly weighted towards understeer at the limit.
However, square setups are proven to be a more efficient way to get around a road course. A good driver on a 10/11' staggered setup wouldn't be much faster (if at all) than a good driver on a 10/10" setup, and the square setup driver would be spending less money replacing tires, since they can rotate them to even out wear. At the cornering limits, you're somewhat limited by the lesser of the two axles. If the front of the car won't turn then the car won't turn, so having a wide 11" rear tire won't help if your anemic front tires can't get the front turned too.
Wide front tires help you get down to the apex quickly. Wide rear tires help you get away and accelerate out past the apex. A track car needs both, but your average street driver generally cares more about straight line acceleration and won't be testing the very scary limits of cornering while trail braking or balancing a car with throttle at an excess of 1.1Gs that the stock PP1 cars are easily capable of.
Ideally you're running a squared setup that is ALSO very wide. That's why people go to extended front studs with slip on spacers to run square 11/11" setups (or the factory Ford 10.5"/11" combo, which is pretty close). Fitting an 11' front is a tight fit. It requires a mix of camber AND just the right wheel offset with little margin for error (~5mm or less at the strut).
The 10.5" PP2 front wheel (and remember the PP2 is a very rare, unusual factory option) pinches the 305 tire down to a slightly narrower size, which allows conservative factory strut clearance, and stock GT fenders without changing the normal stock GT camber configuration. For a track car, a square 11" setup is more economical, and we assume that track car will be fine with less strut clearance (roughly 0.4" less) than Ford Co. will be ok putting on a factory car and will probably be running more than stock camber. As per Ford, the PP2 isn't optimized for the track. It needs coolers, and also, it really needs a bit more front camber.
Porsches and other cars are different. They'll have different power levels, different weight balance, and different suspension geometries. For some of these cars a staggered setup will be faster around a road course.
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with 295 Pilot Super Sports, are notably lighter than my 19x9.5 PP wheels w/Pirelli's (i.e. 5-6lbs lighter!), and there are obviously much higher end, lighter options than RTR's. If we're talking about an option of really low cost, 11" rears, with heavy 325's on them, on stock power, and stock or low-end aftermarket suspension, the weight factor alone might be worth staying narrow. Wheel weight makes a HUGE difference in handling... and staggered = heavier.
