changing rear end gears and tire size

I'm confused...

Simply turning off the overdrive on our trucks is enough to keep it from coming on. It's not like you don't have a choice about OD (like some vehicles). I know you can bounce it off the rev limiter with OD off and it won't automatically come on because I have done it by accident before (got excited in a race...). With overdrive off you can still make it up to about 125-130. I don't know of too many L's trapping 125 or better.

How bad does changing the tire size to simulate a 3.73 throw off the speedo, and even if it throws it off a lot it shouldn't affect the rev limiter. With OD on the truck wants to shift around 120. That said, what kind of times are you running to be clipping 120-125 in the 1/4 and therefore running into this problem?

I only ask because it sounds strange and you are probably the only person I've seen complain of shifting into OD right at the end of the 1/4.

With the SRT-10, you already have 4.10 gears but also have a 31.6" tire. At 6100 rpm (approx. redline) 3rd gear = 108mph, 4th gear = 140. I don't see too many SRT's destined to run 140mph qtr. miles. Switch to a 28" tire and you get 3rd = 95, 4th = 124. Now we're talking. Actually with spray, I would short shift @ 5300 rpm in 1st-3rd, or 89 mph, and then let 4th go as far as it needs to. I would hope someday it's 124 mph.

ediited, no longer have the tires

Trust me I only did it once...