I am very aware of this phenominom and complety agree. But we have to look deeper at this. The force required to start an object moving from rest is what we used to refer to as the Break Free Force or (BFF). This is just the force required to start the object in motion. This time is soo small it can not be measured, it's an instant, unmeasurable it's so small. The exact instant the object starts moving the BFF can not be applied. I did just did look this up in my advanced Physics Text book to make sure I was stating this correctly. So really we dont have to be concerned with this force because it only lasts for a nano-second.

But here are two experiments that will 100% prove to you that a larger sidewall will or will not make a difference. (can you tell that I like experiments?)

Experiment 1
Now this requires physical exercise again so make sure you stretch out properly...we dont want any pulled muscles. Now go upstair and put on your Richard simmons spandex and sweatshirt and go out to the garage. Put the car in neutral and push it. Now slap on the other tires and do the same thing. Do you notice any difference in force needed to move the car? I have slapped my Supra rims on my svx numerous times (225/50/16 vs 225/55/16) and push my car out of the garage early in the morning as to not wake the wife and have never noticed a difference. If you cant tell, neither will your tranny. check out my locker for pics.

Experiment 2
With the 300 dollars you are saving by getting used tires go out and by a tranny temp guage, stick it in and do some planned runs and record temperatures, now throw the larger sidewall tires on and do the exact same run, same driving habits, same outside temperature and record. Plot out a pretty graph on Excel and post it!

Thats diffentative proof. No opinion. Just facts. let us know what you find out. I would do it but I'm poor and cant afford a temp guage.