JL,
thanks for the info; it fills some more blanks in my info banks.
I think that I'll just give my trans a thorough rinsing and leave it alone. if it breaks I'll find out what I need at that time. but if I'm out in a boneyard and find a TH200-4R with the correct letters I now have a better idea which ones are the keepers.
the TH200 has a better set of ratios than most 4-spd OD automatics. it's also smaller and lighter than the others. for engines 300cid or less it's hard to beat.
thanks again, kalklein
PS: my blown Mustang has the Ford "wide ratio gearset" kit which replaces the 2.40:1 first with a 2.85:1 first. though the RPM drop on the 1-2 shift is greater, the launch is much better. I still have the 2.73:1 rear end; 2000rpm at 80mph is relaxing.
