The 3.64 is much livelier about town. Dunno if it is coincidental with changeover from winter fuel, but I saw an immediate increase in mileage. It isn't a huge increase, but it is noticeable.

I was afraid of going to a 3.91 as 1st gear might become useless with my driving style. I'm not big on hanging near redline, though my car does run a bit better after Jeff's drives it.


Quote Originally Posted by mjradin
1990 535im - Jim C Chip

I lost the pinion bearing on the original 3.46.

I love the 3.64 - about 400 more rpms. The increased performance is very nice. A 3.71 would be even faster - at the cost of top end speed. I am very pleased.

Feel free to call if you want more info 617-832-2515

Michael Radin