Yes it will send the wrong speed signals to the computer, you can change the gears to the speed ometer signal generator to correct that though. Check with a good auto tire shop , they should be able to tell you what you need to do.
Depending on if it came with 15" or 16" wheels. 215/70-15" 215/65-16"
Not without changing the wheels also. If you also change the wheels to 17 inch wheels then that is an acceptable swap.
Yes bigger ones are better for rear wheels
215
It depends on what wheels your cougar came with. If you have the 15 inch, six spoke fan blade wheels, you need 205/60 tires, if you have the 16 inch, sport package wheels, you need the harder to find, 215/50 tires. 17 inch wheels were not available in '99 to the best of my knowledge. If you have trouble finding the 215/50/16 tires, both the more common 225/50 tires, and the 215/55 tires can be used without much problem.
215 at the flywheel...185 at the wheels
Yes, if you also change wheels.
215 but they loose 15hp on the drivetrain so u got 200 to the wheels
Yes, you can There will be about a 5% decrease in the tire diameter. 225 65 tires are 225mm wide and 146.25mm in height (65% of the width), while 215 60 tires are 129mm tall, which will affect the odometer and speedometer. When your speedometer reads 60 mph, you'll actually be traveling closer to 57 mph. Replacing the 225 65 tires with 215 70 tires would keep the diameter almost the same (150.5mm).
Smaller profile tires should not affect the anti-lock brakes, but will probably affect traction control.
If you go to a 215/60-15 your speedometer will read 58.8 at a true 60 mph. Your performance, handling, and ride will also be adversely effected. Your decision.
i got the RX8 rims on my mx6 with tire size 215/35/18 and its lowered