Getting ready to put my 29" bighorns on and I want to know how much top speed would be lost with that tires. I really can't afford to loose much more. I'm topped out at 64/65 with 27" bighorns. And I'm also thinking about the shift points. How much does running larger tires affect the shift points in automatic mode. Ideally I would like 28's but 29's is what I have..