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View Full Version : How strong is the e34 auto tranny?



RIPDOTCOM
08-12-2006, 05:43 AM
I am considering a supercharger for my E34 but I am concerned about how well the auto tranny will hold up. I am shooting for 325WHP on my 93 525i

BillionPa
08-12-2006, 06:04 AM
it actually depends on how much torque you are going to be putting down at the crank. i would not exceed 290NM (stock is 250). you would need to tune it properly so that you have a very flat torque band that stays around 290 from when it can all the way to redline.

RobPatt
08-12-2006, 09:01 AM
so good luck...

I am considering a supercharger for my E34 but I am concerned about how well the auto tranny will hold up. I am shooting for 325WHP on my 93 525i

BillionPa
08-13-2006, 12:48 AM
310 is the MAX limit for a new transmission, im sure the 14 year old one will die with that much power.

t_marat
08-13-2006, 02:38 AM
what is the max torque value for the manual transmission of the same engine?

mzarifkar
08-13-2006, 11:32 AM
man i hate the automatic transmissions in our cars. everything on my car works flawlessly except that one pcritical piece that has GM stamped on it!
I know more people have issues with their auto's personally i wouldnt invest in a supercharger without a new transmission (manual)

SharkmanBMW
08-13-2006, 03:47 PM
Scary thought... I can see it now, boosted power and bang, dead tranny.

I doubt our trannies could last very long at their age with any amount of boosted thrashing.

gtopaul
08-13-2006, 08:38 PM
When I installed the M3 S52 engine in my 525iT I used a stock automatic since I drive mostly in the city. HP is probably around 270 since I chipped it and made a few other changes at the same time. I did install a freshly rebuilt auto trans though just to be on the safe side. No problems what so ever.

Paul