Next year I plan on running a mid mount turbo kit with a lower mileage engine I’m having forged internals put in. Currently fbo and tuned with 275/35r19 Kuhmo Ecsta all season performance tires. Wondering if anyone that’s gone boosted can give any input as to what tire size I should run in the rear for it to hook? Was considering 285/40r19 in the summer performance ps91’s and just rolling the rear fenders and raising it slightly. Love being low, but wanna go fast!

 

I'm not boosted with high power, so I won't speak from that experience.

But will speak from a tire engineer's point of view.

Good choice on moving to a summer performance category from the all season. Compound is a major factor. Extreme summer or DOT competition is also good if you need a higher level performing tire.

Summer tires tread pattern design generally have less siping to allow more rubber contact.

With regards to contact shape, tall profile tires give a longer center contact length compared to lower profile tires, which aid in forward traction. The downside of course is tire rigidity. So decide based on if you want something more for drag and straight line or road course oriented.

Your choice of the PS91 in a 285/40R19 would fit everything mentioned above to help with traction over your current all season 275/35R19