[bobinyelm]

This is great! I've learned more already from your posts than I did at multiple websites and reading what I could find elsewhere.

I did a "Search" here, but I didn't do it by differential ratio (I used "tansmission") so it didn't turn up that thread, which was an interesting one.

I believe my W.B. is 93", and I remember reading somewhere (I think it was an article on converting a Mustang to 6-speed) the T-56 is 3/4" longer than the T-5 and TKO500/600, so it might fit OK, but it's pricier than some other options (yeah I know I am being cheap).

The BMW differentials used w/ BDR are available in 3.46 (which again was standard on my friend's Backdraft-I confess I haven't crawled under mine to see if there's a ratio tag), 3.73 (almost impossible to find I understand), 3.91, and I believe 4.11, with 3.91s pretty easy to come by for about $200 used.

I have to see how much they charge to regear a T-5's O.D. down to whatever .75-.80 is available for that. I understand the "World Class" T-5 is a pretty good, yet reasonably priced unit (due to being made in large numbers for Mustangs), vs. what a TKO 500/600 would cost w/ such an O.D. gear.

I will definitely talk with the guys at "Standard Transmission". Didn't know we had a good local source!

I agree that at 75mph the .64 O.D. w/ a 3.5 (+/-) differential is great, but so much of my intended driving is around town where 38-55mpg is common, and I noticed with my buddy's car (.64 OD w/ 3.46 diff) that I was kind of between gears, with the lower gear being obnoxiously loud (in civilized neighborhoods) while the higher gear was almost lugging.

What IS the most popular 6-speed out there (at the best price)? I am not going to be tracking the car, and I will be at or below 400hp, so I don't think I'll need a T-56 w/ the "Tranzilla" option.

While I normally don't like 6 speed transmissions (I see them as overkill), having the choice of two overdrive ratios seems like having your cake and eating it, too, especially for choosing a nice quiet, relaxed cruising gear/engine RPM combination.

Heck, maybe it would be cheaper to convert to an undercar exhaust, or pack my sidepipes with coarse stainless steel wool (as I once did to pass inspection with an old VW dune buggy w/ over-wheel open exhausts in Connecticut). That way, noise wouldn't be a factor (as I suspect it will be if not w/ me but w/ my wife sitting next to me, who would be the one you will see with her fingers in her ears) and I could go with the 5-speed and the lower gear around town. I'm sort of kidding, but I also like the looks of the cars w/out side pipes.

Thanks so much. I am a thirsty sponge soaking this great info up. I'll try not to wear everyone out w/ my endless questions.

Bob