1.9 Z3 steering rack in a (Airbag) 318iS - Few Questions

[rightcoastbias]

I just installed a 1.9 Z3 steering rack into my airbag 318i. It was surprisingly easy to attain the steering shaft geometry to shoot through the firewall.

The only differences between the stock rack mounting were:
-Loosened the passenger compartment flange nut to allow the shaft to extend. Re-tightened flange nut after install.
-Notched the steering shaft's firewall hole ~15mm at 4 o'clock (as observed from inside passenger compartment)
-Placed a 14mm spacers below the rack, effectively raising the rack. (See Image 1 below)
-Mounted the rack in the front tab holes. (See Image 1 below)

This worked for me. The steering knuckle does not bind, nor does the shaft contact the firewall.

Image 1. How I mounted the Z3 rack into my e30.



Open Question:
My concern is I mated the steering shaft's bottom knuckle onto the rack's splined pinion after the rack was back in the car. Anyone who has done this knows how difficult it is to force it in. So far I've gotten it to insert ~15mm and not the >25mm as the stock rack. This decreased joint depth scares the bejesus out of me as I won't be running power steering and the shaft will experience increased torque versus with PS.

Can anyone else confirm this is how they accomplished installing a Z3 rack in an airbag e30 or had a similar bottom knuckle insertion depth and didn't have their steering shaft shear off?

Edit:
Answered my own question: The RMeuropean write up for Airbag rack swap shows the same shorter bottom knuckle with similarly short (~15mm) insertion depth. I'm fine. Image here.

EDIT:
Just for the record. Driving with the 1.9 Z3 2.7 turn linear rack is the bees knees. Wow, just wow.

[driftjunkie27]

I just finished figuring out this too, man im was happy i found out the shaft inside the driver side expands! without this i would have to extend the steering knuckle. anyway im using a e36 rack into my 91 318i , One question. how far can that shaft extend? i was wondering if its safe to do so.

[Nsquared97]

EDIT:
Just for the record. Driving with the 1.9 Z3 2.7 turn linear rack is the bees knees. Wow, just wow.

How do you like it at highway speeds? Is the steering nervous/twitchy at all?

[Sagaris]

How do you like it at highway speeds? Is the steering nervous/twitchy at all?

After a year of my Z3 rack I have gotten so used to it that it feels like a stock rack. But then when I drive an E30 with a stock rack again I cant believe I ever drove with it. It is as stable as your suspension and alignment want it to be. Ive never thought twice about the sensitivity while cruising at high speeds. I honestly wish the rack was even a little quicker.

[Nsquared97]

After a year of my Z3 rack I have gotten so used to it that it feels like a stock rack. But then when I drive an E30 with a stock rack again I cant believe I ever drove with it. It is as stable as your suspension and alignment want it to be. Ive never thought twice about the sensitivity while cruising at high speeds. I honestly wish the rack was even a little quicker.

Good to know (and happy to hear that too) Thanks!

[benz-tech]

Read this: http://www.r3vlimited.com/board/showthread.php?t=253178

I kinda wish the MODs would sticky my thread there. I'm not 100% positive that a Z3 rack is the same, but the bump steer is awful with the spacers on the bottom of an E36 rack. Proven, of course on an alignment rack.

Space that rack down and you will be glad you did.

[Sagaris]

I had insane bump-steer with the spacers above the rack and had a photo of the control arm+tie rod geometry before and after (will have to find it again). Putting the spacers under the rack resolved it. The type of tie rods being used (e30 or e36/z3) is likely a contributor to which position works with the spacers.

[F34R]

After a year of my Z3 rack I have gotten so used to it that it feels like a stock rack. But then when I drive an E30 with a stock rack again I cant believe I ever drove with it. It is as stable as your suspension and alignment want it to be. Ive never thought twice about the sensitivity while cruising at high speeds. I honestly wish the rack was even a little quicker.

This^

I removed PS in mine, drove my Brother's 325e the other day...feels so weird. It is almost not safe, I expect the car to respond and turn fast. I was making a normal corner and almost over shot lol.

It is in my top 3 conversions for the e30. The Z4 shift lever is up there too.

[harv]

I had insane bump-steer with the spacers above the rack and had a photo of the control arm+tie rod geometry before and after (will have to find it again). Putting the spacers under the rack resolved it. The type of tie rods being used (e30 or e36/z3) is likely a contributor to which position works with the spacers.

This is interesting. I haven't checked for tie rod to cont arm allignment yet and need to go Monday to get the toe set but man do I have bump steer. I have the spacers on the top and (I think but can't remember) e46 tie rod ends with a Z3 rack.

John

[Zreberlcoe]

So my rack is completely F'd and brand new E30 racks are stupid expensive for the same damn thing and I want to swap my rack with this E36 or Z3 shinanigan but I'm holding back because of the firewall nothing and what not. If you could explain/show me more in depth of how you did this I would appreciate that sooo much more.

[Zreberlcoe]

And how did you put the spacer exactly and where did you get it?