Os paso un montón de info sobre el tema:
(Para los angloparlantes
From RonStygar_at_aol.com Fri May 14 19:30:48 1999
From: RonStygar_at_aol.com
Date: Fri, 14 May 1999 22:29:35 EDT
Subject: Lets shorten the upper portion of the M-Z3 shift lever
To: dale_at_unofficialbmw.com
The approach to short shifting one's car has addressed the length of the shift lever below the pivot ball. For some time, I and others have been thinking of a viable way to shorten the length above the pivot ball. I wanted to short shift my next car ('00 M coupe) which already comes with the M-Z3 shift lever. This approach would also work for the people who do not like the additional one inch height added by the ERK versus non-ERK. This is also a way to get some more short shift in the E36 M3 or 328 (~9% additional if you shorten 1 inch). This would also work for someone that wanted to keep the stock lever and get a little short shift (M-Z3) while maintaining the stock linkage relationship.
With the help (insight) of Manoj Mehta and Alan Alfano, we've come up with a way to do this that works for me. At the motor mill, my coworker Jim Guyan, who like me, is also curious, made it happen. I had to purchase some stuff to do this. I also had to get my machinist involved. The end result is BMW like in quality (actually better). For the bent prototype, I chose to shorten the upper portion one inch. This will address cars with the ERK. For my M coupe, I went with 1 1/8 inch which results in a 15% reduction (10% reduction if you shorten 3/4 inch, 20% reduction if you shorten 1.5 inch). You could combine this with the UUC Z3 kit and obtain the toggle effect if that's what you like.
Manoj lowered the shift lever 1 3/4 inches in his '97 M3 with ERK. You can lower an amount that you choose. Depending on what lever you choose and how much you shorten it, there are many possibilities.
If interested, for $145.00 I'll supply a (bent for the M3 or 328) shortened M-Z3 lever. For $125.00 I will supply an unbent shortened M-Z3 lever for the M-Z3 or 2.8-Z3. Connect to Dale's image page:
for a dimensioned and comparison look of the above two Z3 stock levers.
I will also be shortening the Z3-1.9 shift lever to replace the M3-328 shift lever in my ti. I like the height of the M-Z3 lever in my 328 and will duplicate this height in the ti. This will result in slightly more throw (<1%) than the M3-328 lever that is in it now.
For now, I have the prototype bent shortened lever in my 328 (same transmission as the M3) if anyone wants to stop by and check it out. Depending on when the lever shows up I should have my ti done shortly. Since I won't have my M coupe for a few months, I have no first hand experience of this mod in a Z3-M or Z3-2.8. If someone in the area would like to stop by with their M-Z3, I will install an unbent shortened M-Z3 lever in your car and we can both find out if we like it. If you like it, you get to go home with it.
The following mod requires attention to detail if you want the result to be BMW like.
Here we go:
At the base of the shift lever outer shell slice the rubber where it meets the shell inward using a razor ~ 1/16 inch. This is so that when you remove the outer shell the lower rubber flap stays behind. Mark the shell the amount that you want to remove. I used a Rigid #20 pipe cutter to do this.
Take the lever to your machinist and have him remove the lower portion of the outer shell to the marked point. You could skip the machinist, but I do not recommend it. I've done it both ways.
Clamp the upper portion of the shift lever in a vice. I made up a fixture out of plywood to prevent marring the lever. Take two pieces of plywood the appropriate size for your vise. Clamp these in your drill press vice with the seam vertical. Drill a hole slightly smaller than the shift lever top at the seam. Using a heat source, heat the outer shell evenly until you start to smell it. You will also get a slight wisp of smoke. Rotate and pull out the inner rubber portion, along with the bottom portion of the shift lever leaving the outer shell in the vice. There is a knack to this which you have to experience (Jim Guyan). You have to get it just hot enough without destroying the rubber. Do not worry about the rubber that you will be eliminating (upper holes).
Chamfer the lower inside edge of the shell. I polished the outer shell. You can skip this step if you do not care what it looks like.
Cut off the upper triangle portion of the inner rubber part using a razor knife where it meets the top of the inner metal shaft. Take care to keep the outer base of the triangle flat. You want the inner part to be slightly concave.
Cut off the upper portion of the inner shaft the amount you chose to shorten it. This has to be done accurately if you want everything to fit right when you put it back together. I used a Lenox 4012 tension type hacksaw. In the future I will be using my bandsaw when I get time to set it up. Reattach the removed triangle part using Lock-tite Quick-tite. Seal the seam with Goop.
Reattach (using Goop at the lower portion (3/8 inch band)) the outer shell taking care to align it properly. The upper part still floats. Lock-tite Quick-tite the lower flap to the bottom edge of the shell.
Rather than crimping, I seal the inner shaft to the rubber using Lock-tite Quick-tite via a glue needle. Not sure if doing this is correct. Since the upper portion of the inner rubber is not glued to the outer shell, and the lower portion of the rubber is not glued to the inner shaft, I suspect that this was by design.
Fill/seal the two upper ports (no holes now) using Phenoseal liquid caulk. You could probably skip this step, but I feel that it gives the lever a finished look and another lock point. I place a BMW logo over one side. Finish polishing and seal the upper shell. I use Nyalic which is available from Eastwood for $12.99 per 12oz spray can. Again, you can skip this step if you do not care what it looks like.
Ron_at_unofficialbmw.com FLY BMW Marlborough, CT
http://www.unofficialbmw.com/ronstygar.html
