[Frank Messina]

How old are your tires? I'm asking because Cooper doesn't currently offer a 265-60-15. That aside, depending on your wheel clearance a good combination with a 295-50-15 would be either 235-60-15 or 245-60-15 on the front. You don't want the fronts to be the same diameter as the rears and most definitely not larger. If the car felt squirrely it could be your tires are overinflated. Every tire shop on the planet wants to send you out with 35+ pounds of air in the tires. They'll be rocks for sure especially on a car as light as a Cobra. Too bad you took the power steering off, as that wasn't your problem. You needed more caster and less air pressure. Also you could reduce the assist by adding a Heidt's valve to the power steering without slowing down the steering which does wonders for the feel.

I have 235-60-15 front and 295-50-15 on the rear at 23 and 26 lbs respectively. My car is IRS and weighs about 2400 lbs. I just replaced my Dunlop GT Q's which I loved with Mickey Thompson Sts. The MTs are made by Cooper and so far feel like the Dunlops although I haven't really pushed them hard yet as I only have about 100 miles on them. FWIW

Frank