Question:My TH400 trans(non-switch pitch)has the 2.48/1.48/1.00 gearset,and I had the trans done at Superior Transmissions,Silver Spring MD.I heard that the "BB"TH-400 had the 2.75-1st gear set,and certain motorhomes (RV's)have that gearset as well.What advantage/disadvantage is there to having a 2.75 gearset in a TH-400 in a street/strip trans?anyone out there using a 2.75(0r higher)gearset.I explored the possibility when I was thinking about putting one in my TH-400 in my '74 Riviera,because the 9-3/8" rearend didn't have a ring and pinion higher than 3.42(back then the car had 3.23's in it.)but,if anyone has a trans gearset higher than 2.48,could I hear from you,the advantage,if any. Thanks,Jay B.Britt,Jr.
with a 3.42 rear a regular TH-400 will give you a final drive of 8.488 and the RV gear will get you 9.405