3.73 Diff swap

[mysticzhp]

Hey guys just wanted to say I finally got a diff for my car after I got stood up for the 3.64 from a seller. I came across and awsome deal on a 3.73 from a x3 smg. The buyer I purchased this from had it installed in his Z4. Now my question is the it seems to have a 6 bolt flange which should be the same as my car and should bolt up with my driveshaft. But I have read on google searches that if swapping a diff into a 330 you need to swap out the flange and change the driveshaft from any other e46 other then a 330. Anybody know about this swap that can help me out. Thanks guys.

[slater]

Hey guys just wanted to say I finally got a diff for my car after I got stood up for the 3.64 from a seller. I came across and awsome deal on a 3.73 from a x3 smg. The buyer I purchased this from had it installed in his Z4. Now my question is the it seems to have a 6 bolt flange which should be the same as my car and should bolt up with my driveshaft. But I have read on google searches that if swapping a diff into a 330 you need to swap out the flange and change the driveshaft from any other e46 other then a 330. Anybody know about this swap that can help me out. Thanks guys.

first off - awesome idea, the 3.73 will be SUPER aggressive though. curious to see how you like it.

second - post some pics of the flanges so that we can see what needs to be swapped.

[mysticzhp]

Sounds good I'm gonna go downstairs and snap some pics I'll be back in a few minutes.

[mysticzhp]

Sorry for the crappy cell phone pics but this is the best I can do for now.

[slater]

OK, so you're going to have to swap your input and output shaft flanges - not hard, but you'll need a 30mm socket for the input shaft flange (i just did this a few weeks ago). obviously you're swapping the rear cover, too. you shouldn't need to change anything else.

[mysticzhp]

Yes I'll reuse my fined cover. So I guess I won't need a driveshaft from a different e46. I read somewhere that the 330 driveshaft was too short and I have to swap for a 328, 325, or 323.

[NoVAphotog]

I don't know if it's worth it for 3.73...have you driven anything close to that ratio to see what it's like? People complain about 3.64 on our cars...INCREDIBLY short. I can't imagine 3.73. Easily 3300+ rpm above 60mph and most likely a non-existent 1st gear. Basically will be turning your 6 speed into a 5 speed. :/

[derbo]

The only person that I know that was using it was Steve. Sna77
http://www.zhpmafia.com/forums/showt...00-(Boston-MA)

3.64 is already pretty damn short. I have the M3 rear end at 3.62 and its alot of shifting but uber fun for street driving.

[slater]

Yes I'll reuse my fined cover. So I guess I won't need a driveshaft from a different e46. I read somewhere that the 330 driveshaft was too short and I have to swap for a 328, 325, or 323.

no, your existing driveshaft should be fine. you can always measure the casing compared to yours but i have to believe it's the same casing.

I don't know if it's worth it for 3.73...have you driven anything close to that ratio to see what it's like? People complain about 3.64 on our cars...INCREDIBLY short. I can't imagine 3.73. Easily 3300+ rpm above 60mph and most likely a non-existent 1st gear. Basically will be turning your 6 speed into a 5 speed. :/

i believe that will put 75mph at around 3300rpm in 6th. pretty short, however i had an acura integra type-r that sat at 4200rpm at 75mph in 5th. and that was stock!

[mysticzhp]

I've had a few mustangs with 410's I know what I'm in for. I'm building my car to be track/ weekend street car. The guy I got it from said his z4 at 70mph was at 2900rpm.