1 (edited by SharkBait 2009-06-22 01:36 PM)

Topic: Safety Note: BMW Steering Flex Disc E28/E30

We tore our steering flex disc the other weekend at Buttonwillow. Fortunately, it was in the pits and not on the track as it completely isolated the steering from the wheels.

http://www.ianwood.com/images/db/medium/pre-butt-009.jpg

http://www.ianwood.com/images/db/medium/pre-butt-014.jpg

Its a rubber bushing much like the driveshaft guibo (also notorious for falling apart) that sits half way down the steering column. We pulled the power steering a long time ago and low speed steering is obviously putting a lot of strain on the steering column flex disc. We are going to fab up an aluminum joiner plate to take its place.

Just wanted to make everyone aware just in case yours is on its way out. Might be worth a five minute inspection just to make sure.

The Sharks
Home of the E28 Turbo Tuner Fish and the Hammered Head 944 Turbo

Re: Safety Note: BMW Steering Flex Disc E28/E30

This is part of the reason why we decided to leave the power steering intact on our car - not to mention the fact that we'll be autocrossing it which isn't easy with manual steering. Good head's up!

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.

Re: Safety Note: BMW Steering Flex Disc E28/E30

Yeah definately good pointer to anybody not really familiar with the BMW steering linkage setup. I've seen LOTS of cars with really bad looking flex discs. BTW they do sell a nice poly replacement for ~$20

Re: Safety Note: BMW Steering Flex Disc E28/E30

SharkBait wrote:

guibo

Nothing valuable to add, just that I love the word guibo.  Guibo, guibo, guibo, guibo, guibo.

Ahh, much better now.  big_smile

TST, fool.

It's a Bunny.  With a pancake.  On its head.  Really, is it that tough?

Re: Safety Note: BMW Steering Flex Disc E28/E30

Some BMWs have a second similar flex disc in the engine compartment in between the firewall and the steering box. My 2002 does.

Re: Safety Note: BMW Steering Flex Disc E28/E30

FWIW I removed the power steering belt from our car to gain an extra 1.5 HP for drag racing (yes, seriously) and holy cow, power steering is so not necessary on our car. Turns super easy, even at low speeds. Of course the E30's 4 turn lock to lock rack may have something to do with that.

I checked the steering shaft from end to end and I couldn't find a steering guibo so I guess I don't have to replace it!

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.

Re: Safety Note: BMW Steering Flex Disc E28/E30

LTDScott wrote:

FWIW I removed the power steering belt from our car to gain an extra 1.5 HP for drag racing (yes, seriously) and holy cow, power steering is so not necessary on our car. Turns super easy, even at low speeds. Of course the E30's 4 turn lock to lock rack may have something to do with that.

I checked the steering shaft from end to end and I couldn't find a steering guibo so I guess I don't have to replace it!

You were wise to take into consideration the implications before doing so. We on the other hand ripped it out before our first race not considering anything other than weight/complexity reduction. Before that race, I was seriously concerned about the potential upper body workout that we might face lacking PS but fortunately it turned out to be just fine without it. In fact, you probably get a much better feel for the track without PS.

And being such fine menchanics that we are, our steering box still sits wide open with two hoses pointing up to where the PS pump used to be. No ill effects so far. We have plans to seal it up in 2010 or 2011 or thereabouts.

The only thing you may want to check is the link to the brake booster on E30s which is different than E28s. Don't remember what specifically what it was.

The Sharks
Home of the E28 Turbo Tuner Fish and the Hammered Head 944 Turbo

8 (edited by LTDScott 2009-06-30 03:19 PM)

Re: Safety Note: BMW Steering Flex Disc E28/E30

( <-- Works for steering parts supplier):

You really ought to have some fluid in the box for lubrication. Loop the lines together and you should be fine.

I wouldn't have even thought to check the steering joint if it wasn't for this post, so it was a good heads up. I'm guessing maybe only some E30s have it? My parts catalog shows one listed for my car but it's definitely not there.

edit: Thanks BMW for hiding this behind the brake booster. I'll have to contort my head down there to take a look.

http://www.realoem.com/bmw/diagrams/n/k/8.png

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.

Re: Safety Note: BMW Steering Flex Disc E28/E30

That's more evidence that even BMW hates BMW drivers. smile

It's like being an anti-dentite: I can say that because I'm currently on my 3rd BMW (an e21 and 2 e34's). Now that BMW has de-Bangled its design department, perhaps they will return to the beauty of the days of the shark nose. The e34 is still far and away my favorite 5-series design, but the new M3 Coupe looks damn sexy. Alas, if only I had $60k to burn.

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.

Re: Safety Note: BMW Steering Flex Disc E28/E30

The "rag" joint is common in many cars especially American iron with recirculating ball steering....always worth a look during your build and I suspect you wouldn't have much trouble arguing that the cost of a new one should come in as a "safety item" at tech....

Jim "Endo" Anderton
30 years of racing and still not Brambilla.....

Re: Safety Note: BMW Steering Flex Disc E28/E30

I found our steering guibo and it's fine. I have no idea how you'd replace it if it were bad anyway... but I did discover this:

http://www.ltdlx.org/albums/cage/guibo.sized.jpg

This guibo was installed brand new in 2/08. Good thing we caught it, because it looks like the holes were elongating and would eventually fall. Too bad it took us breaking a transmission to find it sad

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.