[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

First 325iX with Ben Liaw inspired Short Shift ? [Long]



On Saturday Sept 26, 1998, I completed what could be the first E30 325iX
Ben Liaw inspired short shift.
I already have 2 BL inspired SS upgrades under my belt, as I have helped
Ron Stygar upgrade a 1996 328iS and a 318ti.

The E30 325iX conversion to a BL inspired SS is a little more difficult
that the normal E30 325.
Where one can normally reach around the transmission tail portion to change
the shift lever; in an iX there is an auxiliary transmission that sends
power to the front driveshaft/wheels  (the iX was BMWs AWD vehicle from
1987-1991). To gain access, I removed: the cat-back exhaust, head pipes,
cat and drive shaft. The rear transmission bracket was removed and the
engine/trans unit was lowered/rotated by using garage jack.

Access was then accomplished from the driveshaft side.  I was only able to
remove the clip between the selector rod and shift lever. The front
selector rod clip is a round circlip and is different from the rear clip.
Even with my long arms (35 inch sleeve length), I was just able to touch
the clip and after an hour of trying to remove it, it was deemed to be
impossible to remove it without removing the auxiliary transmission or 5
speed transmission. (which I did not want to do)

IMHO it is important to bend the selector rod by the same amount that was
added to the shift lever. The iX straight selector rod should have been
bent in the middle resulting in a downward bend of 1/2 inch. This would
have resulted in the same unmodified selector rod angle of attack into the
transmission via the gear selector rod joint. That way, the notchiness and
its related excessive force would be eliminated from the short shift
conversion. Without the bending of the selector rod, the shifting is
notchy, as the angle of attack is no longer straight into the transmission,
but is now up and then straight into the transmission. This was observed
and measured during our first two BL/SS inspired conversions.
Note that this does not reduce the additional force that is required due to
the increase between the shift lever ball and selector rod assembly hole.
IMHO this is just fulcrum physics.

In my prior BL/SS upgrade experiences, there was enough room to get ones
hand vertical to gain leverage for removing the plastic lever cup. In an
iX, the available hand rotation is horizontal to 45 degrees, which is not
enough to gain any leverage. Also there is not enough room for access from
the drivers or passengers side.
The plastic cup could not be rotated out as been done on other cars and the
crossed screwdrivers technique only took chips of plastic off. As the
original shift lever ball is metal and not plastic like some new BMW
levers, I was able to remove the shift lever from the cup by melting the
plastic cup with a soldiering iron. Once the shift lever was removed, the
cup was then levered out with a screwdriver.

I purchased a used 1995 M3 shift lever for my conversion.
Dimension comparison:
1) Between shift ball and selector rod mounting pin assembly:
    iX: 1/8 inch, M3: 5/8 inch;   net gain = 1/2 inch.
2) upper portion of the shift lever:
    iX: 6 3/16 inch, M3: 6 11/16 inch;   M3 is 7/16 inch taller.
3) Neutral position:
    M3 shift lever is 1/4 inch closer to the dash and 3/8 inch closer to
the passenger door.

If I did another iX, I would use a shift lever from a Z3 1.9L (PN
25-11-1-434-148). This lever has the same 5/8 inch distance between the
shift lever ball and selector rod assembly hole. Upper shift lever length
is slightly longer (iX: 6 3/16 inch  vs  6 1/4 inch  =>  1/16 inch higher).

Some shift lever binding occurred when the rear transmission bracket was
bolted up to the chassis. This problem was solved by shimming the bracket
from the chassis by using two flat washers on each of the 4 securing bolts.
All new nuts were used for the exhaust system and driveshaft.

Shift lever distance reduction:
1 to 2:           22.85% reduction
2 to 3:           17.14% reduction
3 to 4:           18.75% reduction
4 to 5:           21.21% reduction

I also removed the clutch pedal freeplay as shown on Ron Stygars homepage:
http://www.eskimo.com/~dalus/bmw/bmw_ronstygar.html
http://www.eskimo.com/~dalus/bmw/all/drivetrain/all_clutch_stop_adjustment.
html

This modification eliminates the clutch pedals ~35mm of free play from the
bottom of the clutch pedal stroke.
The combination of the BL inspired SS and eliminated clutch freeplay is a
great combo.  Try it !

The BL inspired SS is a absolute delight to drive.  As expected, due to
selector rod not being bent, some notchiness now occurs. Redline MTL was
already in the transmission.  After 200 miles, the new cup and washers are
broken in, resulting in lower shifting effort but still more than stock.

THANKS go to the BMW-Digest, Ben Liaw and Ron Stygar.

Regards,
Alan Alfano
alan.alfano@domain.elided

BMW CCA #30492
iX Registry # 214

1988 BMW 325iX
1956 Austin-Healey 100M (2)

------------------------------

End of bmw-digest V9 #276
*************************