Is the BMW differential strong enough to
handle the power and torque of the LS1?
BMW has three families of diffs. The 6 cylinder E36 comes with
the medium size differential. Right now I am running the
medium size diff in the ti and so far the internals, axle shafts,
and CVs have not complained. This includeds tons of burnouts,
trips to the strip, and countless hard shifts. I have been running
BFG G-Force KD 225 45 ZR18 which is a very good street tire.
If you have a 4 cylinder car then you have the small diff and it is
not recommended for this swap. I suggest you get a rear
suspension from a wrecked 6 cylinder car.
One issue you will have is the front mount bolt in the E36 is
prone to breaking and will break if it is not reinforced. I drilled
mine out and replaced with a larger diameter high strength bolt
& nut. You can also find a kit @ www.aatuning.com to replace
the factory setup.
The other issue is controlling the rear subframe movement. With
the power of the LS1 the rear subframe will move under hard
accelerations. This needs to be controlled to keep from tearing
things up. Installing a good set of urethane bushings will
eliminate excessive subframe movement. This is critical on the
ti and Z3. These cars use the rear suspension from the E30 and
the subframe movement must be controlled or you will break the
mounting ear off the differential and be walking home!
Does the kit include everything I need to
complete this swap?
Yes! I have tried very hard to include everything needed to make
this swap. If you have to go out and buy something I want to
know as my intent is for the kit to be very complete right down
to every nut, bolt, tie strap, and connector you might require. AC
hoses and fittings are optional.
However, if your motor is from a production car then the PCM
has a vehicle anti-theft system (VATS) that has to be defeated.
The PCM also looks for emission equipment to be present and
functional. If it does not find the emission stuff it will set
engine codes and your check engne light will stay on.
There are two ways to get around the VATS issue. You can
purchase a VATS & dual O2 override module from
www.bakerelectronix.com for $45. This module will allow the
motor to start and run in full power mode however your check
engine light will remain on. The other option is to have your PCM
reprogrammed to eliminate the emission checks.