E30 325ix steering rack swap

[ziazhp]

Does anyone know if there any swaps available from other models, etc?
I know with the RWD E30 you can use a ZHP or a Z3 rack, but what about the 325ix?

[nando]

Nope. E46 xi rack is close, but you'd have to modify the subframe, tie rods, and steering shaft. And nobody has done it yet.

[stonea]

It's still the one thing that just bugs me about my ix, but Nando is right, the e46 xi rack is the closest bet. I would love to buy one and try to fit it, I just don't have the time, money, or resources to do it.

[dave.a.cote]

Has anyone tried to swap an e46 rack gear and pinion into an e30 housing?

[madman23]

Nando. Can you make a swap kit so I can just buy it? Lol. I know you have done a ton of research on this and it doesn't seem like the steering quickener is going to happen this season.

[nando]

A kit? Hmm. Well, I don't know about a kit - but maybe I could get a couple sets of subframes modified?

I'm pretty sure the quicker E30 ix rack is never going to happen. I've decided I'm just going to go forward with the E46 rack myself, although not until I have the new motor ready. It actually doesn't need a whole lot of modification - some clearancing of the subframe for the "knuckle" on the steering rack, modifications to the mounting points (I was thinking of adding some steel inserts or something like that). Garagetastic can make a U-joint for it - you just need the length measurement. The E46 tie rods would be easy to shorten yourself. The only remaining difficult part would be enlarging the holes slightly in the struts to fit the larger E46 ball joints - ForcedFirebird can do that but he's in Florida.

If you live in an area that sucks less than mine, you can probably get all of that done locally pretty simply. Here, fabricators only want to touch big projects.

There will be some increase in bump steer but I decided I can live with it for the quicker ratio. The E30 is like driving a bus in comparison to a more modern BMW - even our X5 has sharper steering.

[madman23]

You sir are awesome. I need to find a steering rack but due to SEMA this project won't happen until net year:(

[nando]

Had a look back at my thread on E30tech:

http://www.e30tech.com/forum/showthread.php?t=108108

I think the spacer idea is still valid - a simple extruded bar with 4 holes would work just fine. I would probably bolt it all the way through the subframe, in addition to using the existing bolt holes. That would make modifications to the subframe minimal. You would need to shorten the E46 tie rods slightly, and enlarge the holes for the ball joints. Once installed, take measurements and have Garagetastic make you a custom column / U-Joint. I still have an E46 M3 U-joint that I can use for it.

Since the spacer will change the bump steer curve I think it would only work with a lowered car - it may also help counteract the fact that the tie rods are a bit shorter than stock. The engine possibly needs spaced up a bit but that probably isn't a big deal, unless there is CV shaft interference with the frame rails (I'd probably just raise the car up a bit - mine is pretty damn low).

[dave.a.cote]

Has anyone looked at e90 racks? Or even racks from non-BMW's?

[nando]

E90 xi racks are really awful - no feel, slow rates. Not really much better than the E30 ix, and it's a bigger car so fitment probably isn't better.

as far as other makes, well, your guess is as good as mine - maybe if you rebuilt racks for a living, you would know of racks that have similar dimensions and better ratios. But they probably would still have the same fitment issues - some sort of adapter plate, tie rods, and U-joints need adapted either way.

[dave.a.cote]

From what I have seen:

e30 is 20.5:1
e30 m3 is 19.6:1

e36 is 15.4 to 17.6:1 depending on version

e90 xDrive is 18:1

Not great but would take steering from 4.0 turns to 3.5... maybe poor e90 feel tied to other factors like caster/weight...

Just thinking about getting my ix ready for winter and I know it needs a rack and I would rather not spend a few hundred dollars on a stock replacement that I know I will be disappointed with.

We are going to be building some custom steering racks for the vehicles we make at work, I will keep the ix in mind to see if there is something that we can do.

[nando]

We had an E90 xi - trust me, faster or not the steering feel is not good. Especially compared to a RWD E9x...

[madman23]

Would I be able to use e36 ends on a ZHP rack so I dont have to drill the hubs?

[nando]

I don't think so. They're the wrong shape, and probably the wrong length. (I believe the E36 rack is pretty short, where the E46 xi rack is fairly long).

The RWD tie rods don't have the bend in them to go around the swaybar like the AWD ones do. If you look at the E30 ix and E46 xi tie rods, they have the same shape to them.

[The Dark Side of Will]

Is that bend for the sway bar or to clear the inner edges of the wheels at full lock?