S52 Swap with ZF and 3.46 Diff?

[ksjdan]

I have a swapped car with a S52 and ZF (stock off e36 M3). Im thinking about replacing my 3.73 for a 3.46 due to a high cruising rpm. What are your thoughts on the swap? What would be the cruising rpm when im going around 80 mph?

[djjerme]

Should be fine. Also can go with a slightly taller tire to help as well.

[jeffnhiscars]

I'm running a 3.46 with an auto trans and IIRC it runs at about 2800-3000

[M-technik-3]

Will be buzzy but great acceleration, it's liveable that is for sure. I have same combo and it's fun would prefer one more gear aka 6 speed and it would be perfect.

[dude8383]

Gearing Calculator that I saved years ago:

https://www.dropbox.com/s/zraie1vsfqr9je6/GearingCalculator.xls?dl=0

it'll be buzzy like the others have said. a 3.25 would be better suited for daily driving especially if you're commute involves highway roads.

[M-technik-3]

You gave us the 2.93 combo but op has site where he/she can plug in data or

These guys used to list the e36 stuff.

http://www.bokchoys.com/differential/e46_gear_ratio_calculator.htm

guess they don't anymore

[dude8383]

You gave us the 2.93 combo but op has site where he/she can plug in data or

These guys used to list the e36 stuff.

http://www.bokchoys.com/differential/e46_gear_ratio_calculator.htm

guess they don't anymore

all of that information is editable :up:

you punch in the gear ratio's, tire size and final drive ;)

[M-technik-3]

Yeah knew that, just they used to have a quick reference way of doing it.