How To Guide - E36 Steering Rack Swap

[Schniddy]

Originally Posted by JGood

That's a good deal as long as it's the quick ratio 2.7 turn rack (it's not the 3.0, but for that price who cares?)

It looks like its the 3.2, if there is such thing. Isn't that the same as the regular 325 rack? Not worth it then I'm guessing?

[RobertK]

Originally Posted by JGood

That's a good deal as long as it's the quick ratio 2.7 turn rack (it's not the 3.0, but for that price who cares?)

3.2 is fine for that price.

A Z3 2.7 rack is a just 3.2 with less turning radius.

[JGood]

Originally Posted by Schneider325

It looks like its the 3.2, if there is such thing. Isn't that the same as the regular 325 rack? Not worth it then I'm guessing?

I would still do it. It's .2 turns longer. That's .1 turns each way. If you can even notice that, I'd be surprised.

[wazzu70]

I did the steering rack swap this weekend and I put up some pictures I thought would have been helpful to have before starting. This is using a 95 M3 rack and its going into an airbag car.

E30 and E36 rack side by side:

I had never seen an e36 rack before, so I was always curious what the difference was.


I cut back the firewall insulation and pulled the shaft grommet out. You can see the plate that people reference.


This is with the rack installed and no part of the firewall cut, you can see on the column shaft where its rubbing on the plate by the shiny marks.


I cut away the plate material to match the firewall with an end mill style bit.


This is with the rack installed and the plate ground to match the firewall opening. The column shaft is still rubbing on the firewall even though you can install all the components.


This shows my estimate of how much of the firewall I needed to grind out, it was more than I initially thought I would need to remove.


After the firewall material was hogged out you can see that the shaft does not rub on the firewall any longer and has some clearance for the rubber grommet to go back into place. FYI I cut some of the carpet that the shaft was rubbing on out of the way from the interior.


With the rubber grommet installed.


Finished product.

No material was removed from the universal joint.

Obviously this was pretty easy with the engine removed, but I wouldnt want to try and hog out that much firewall with the engine and components in place. I did test fits multiple times before I removed that much material and the steering column shaft still rubbed on the firewall up until that point. I wouldnt reccomend anticipating the removal of less material and having a smooth steering feel.

Hopefully this helps give people a better idea of what is required to swap an e36 rack into an airbag car.

[Jean]

Originally Posted by Schneider325

It looks like its the 3.2, if there is such thing. Isn't that the same as the regular 325 rack? Not worth it then I'm guessing?

Is there more than one for sale at that price ?

[etxxz]

well and i finished mine. My rack came with its 1995 tie rods on it so i left them and did an eye-spec alignment but hey they work just as good i'd be surprised if they dont have the same ball joint. Took for a test drive and all works nicely and even my alignment is good but i'll take it in anyways. ty for the thread robert!

Here's a pic of the modified stock line. It basically needs to bends, one to open the curvature ever so slightly and anotherone to change the angle of the piece that connects to the new rack ~ 15-20degrees

use the stock metal piece of the line that goes to the resevoir and you just have to trim and inch or two, clamp and good to go.

e36 inner and outer tie rods ... hey i paid $4x.xx for all that. I used washers for spacers on the rack and knuckle so my entire swap including new bolts was under $50.


for those wondering i think its necesary to trim the upper side of the knucke because it will bind so just eat up some metal while you have it off the car and save some time and having to pull metal shavings out of your nose

[bmwaddict]

Now doing my 1995 E36 m3 steering rack swap, scroll down to my project page please on my forums, it's time consuming to repeat posts.

http://bmw.turboready.com/phpbb2/vie....php?p=831#831

Below is a pic of the rack I am installing. We pulled out the subframe to do a full restoration, today we will sand blast, prime and pint the sub frame. Will post pics later.

New 1995 e36 m3 rack.



Machining spacers.



Spacers



Spacers being test fitted.

[RobertK]

Originally Posted by JGood

I would still do it. It's .2 turns longer. That's .1 turns each way. If you can even notice that, I'd be surprised.

I usually don't recommend it because with the z rack you lose turning radius and you pay more for it when you can get a standard E36 3.2 rack for less.

[JGood]

Originally Posted by RobertK

I usually don't recommend it because with the z rack you lose turning radius and you pay more for it when you can get a standard E36 3.2 rack for less.

I was under the impression that the 2.7 z3 rack was the same ratio as a 3.0 95 M3 rack, with less lock-to-lock movement.

[RobertK]

Originally Posted by JGood

I was under the impression that the 2.7 z3 rack was the same ratio as a 3.0 95 M3 rack, with less lock-to-lock movement.

IIRC it's a 3.2 minus .5 turn to lock ratio = 2.7 rack.

[1991 318is]

There are steering stops on the control arm/hub. These limit the rack travel. On the Z3, is the rack itself not capable of turning any more. The actual spec for rack quickness is given in terms of pinion rotation to rack travel as turns lock to lock can vary from one model to another. I put an E36 rack in my 1991 318is. It went from 4.0 lock to lock to 3.2 lock to lock. It was a noticeable improvement.
You've provided very good pictures of the firewall modification. I had to do mine from the inside of the car by pulling out the lower shaft from the column for room to get a rotary file in there.

[bmwaddict]

The steering knuckle is so much shorter on the air bag eqqipped e30's compared to the non air bag ones.
Though my steering knucke is in very good condition I was still thinking of replacing it with a new one, could not believe the nearly $ 300.00 price tag at the stealership, will have to call my parts suppliers to see their cost on it

Making the steering column port bigger is a BPITA indeed.

Today I made engine mounts reinforcement plates for my subframe, welded them in, sandblasted, primed and painted the subframe.

Will get some new grade 8 steel bolts and hopefully start test fitting tomorrow.



Here I made the engine mount reinforcement plates, have to re drill the engine mount holes when done.



I welded in the plates and sandblasted the subframe


Primed it



And applied two coats of high temperature enamel paint.



Will hopefully test fit tomorrow.

[matt]

So, I haven't tried this swap yet but I have a question. Is it possible / does anyone put the spacers below the rack?

That would reduce bumpsteer in lowered cars by moving them closer to the stock tie rod angle, it seems like. Is there any reason you couldn't?

[erik325i]

Originally Posted by matt

So, I haven't tried this swap yet but I have a question. Is it possible / does anyone put the spacers below the rack?

That would reduce bumpsteer in lowered cars by moving them closer to the stock tie rod angle, it seems like. Is there any reason you couldn't?

I've already thought of that, and that was going to be my next project. I think it will work. The clearance between the rack and oilpan is going to be very close though...

-Erik

[erik325i]

Originally Posted by RobertK

IIRC it's a 3.2 minus .5 turn to lock ratio = 2.7 rack.

That's not true. The Z3 rack has just as quick (if not quicker) steering than the '95 M3 rack. It is not the same ratio as the normal e36 rack.

*And this in not just info that I "read somewhere". I own a '95 M3 rack, "97 M3 rack, Z3 rack, and an e30 M3 rack and I have personally compared the ratio between the "95 M3 and the Z3 rack.

-Erik