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tibbs.james

E36 Rack into an E30 Conversion Write up

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Hi Guys I should say this is a conversion for e36 steering rack into E30 could a mod fix the title please ?

This is my progress on swapping to an E36 power steering rack.

Step one, make sure you have a nice tidy e36 steering rack

Step two, Make up some nice alloy spacers, file them nice and round so they match the mounting points on the 36 rack and paint up nice and clean to match. Use one spacer top and bottom each spacer is to be 6mm

Step three, mount the steering rack.

Step 4, Take apart the E30 & the E36 steering linkages. Fit the Top U Joint from the e30 to the spine on the steering column. Fit the lower E36 U Joint to the E36 steering rack and measure the distance between each face so you know how much polyurethane to cut.

In my case it was 33mm.

Step 5, Cut and Drill your Polyurethane Rod. I used a Drop band saw to cut it very slowly as the blade tends to wander around otherwise. Then when it came to drilling i used a drill press and a clamp. Once again drill very slowly so you don't make a mess of it.

Holes need to be 8mm spacing at 45mm & 50mm Rotated 90deg. Not sure what the center hole was i think it was a 14mm.

Step 6, Build up your steering Joint. In the end my poly block ended up being 27mm so it would stay protected by the heat shield and I used another 6mm spacer on top of it at the Steering column end.

Make sure you use the bolts use you use are High tensile and are the ones that are smooth where it goes through with a step and threaded part only at the very end. I used washers and spring washers on each bolt so that nothing has any chance of loosening off.

Step 7, Fit up your Steering Joint, Take lots of care to make sure you do your own measurements during the whole process as where the pinch bolts go through the splines at each end there is a recess cut for the bolt to go into ant the bolts have to be positioned exactly right or they will not clamp up onto the spline properly.

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Edited by Jimmy

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At this stage I am assuming most people who do this are going to loop over the lines and run it as a manual rack.

I am going to have custom Power steering lines bent up and retain the power steering.

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Good work on the write-up!

Make sure you report back on how it feels too.

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I should Really get off my ass and make the polyurethane engine mounts for it too

BTW the poly rod is 90a duro automotive grade and is the same as what everybody else uses for bushings ect. It is 70mm diameter and 300mm length . It was $110 from Mulford Engineering Plastics

I wouldn't bother going near the poly unless you have a band saw and a drill press.

( Dads garage is good like that )

I have found out the E36 low pressure line ( to the fluid resivour ) can be used if as long as you make a cut where the metal stops and hose clamp the rubber hose to this.

I will try and get a picture of this tomorrow - its all cold outside now.

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Nice work Jimmy. Always good to see decent write-ups of what people are up to. Title sorted too :)

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This thread should probably go into projects... good write up Jimmy

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Worthy of sticky. Good stuff.

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Which rack did you use? There are tonnes of different ratios and lock to locks within the E36 range.

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Nice write up. This is also covered in the 'BMW e30 - 3 series restoration bible' by Andrew Everett.

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Which rack did you use? There are tonnes of different ratios and lock to locks within the E36 range.

I understand the Z3 has the best ratio

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I understand the Z3 has the best ratio

Yes indeed, if 1.9 lock to lock is your thing at high speed, there are other racks with the same ratio, but slightly more turns lock to lock, hence the question, so when it's all done and we get a report back on how if feels in an E30, we can gauge whether we want to go more direct or not.

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Definately up there on the list of things to do. Its really the only thing i dont like about the e30. When your cornering at speed its a bloody hassle. I want the rack out of that RUF Yellowbird :D

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Hi Guys

I did this swap out of concern for reliability not for steering speed.

I had 2 FL alloy E30 racks fail on me without warning and they both failed in different ways

The steering rack I got was from a 1992 E36 , i think its the 3.2 lock to lock version( slowest of the e36 range ?) Its not a flash one like other people might be after.

But i am most impressed with how the rack is beefier in every respect over the E30 steering rack. And the general consensus was that the E36 racks never gave problems, A number of bmw wreckers have told me this & also a power steering rebuild shop.

But the test drive will take place this weekend, once my High Pressure hose is built up this week.

More Pictures to come soon.

Edited by Jimmy

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After having a look at Power Steering Hard Lines I have found out the following.

1- you can use the E36 low pressure line, remove the rubber hose, and trim off the mounting tab where it bolts to the E36 rack- if you leave this tab on it will rub against the sump

- I am yet to come up with a brackett or something.

2- it might be possible to join the E30 High pressure line and the E36 High pressure line.

you can see how I trimmed up and bend the E36 line. I had to bend the E30 hard line quite a long way and its a tight fit in there but this could possibly work.

One problem might be that as the lines are different diameter they may be impossible to join properly.

I am still thinking that an Entire new hard line may need to be built- however i will attempt to have these 2 connected and see how it goes.

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Hi Guys

Tonight i got some good work on the car done.

I went to see my engineering friend who tig welded my steering lines together, he drilled the inside of the fat end then countersunk the thin end "step or lip" was a smooth transitiom for he fluid inside the pipe and proceeded to weld together, quite simple really!

Here is the result.

And you ask how does it drive ? the answer is AMAZING !!!

For steering around corners that i had to really " turn" the wheel its more like a nice fast flick and its all done.

It feels very responsive And I am loving Evey minute of it.

However I am considering placing both my spacers underneath the steering rack to allow more room for the power steering lines as they are rather squashed in there right now.

And the more i think of it the 6mm spacer between the poly and the upper U joint could be removed and this would allow more of the centering pin to slide up into the Upper U joint as per a factory one.

The E30 power steering pump seems to do a good job with no groans or moans and the steering effort is about the same as before, it seems to not require any more effort.

All in all I rate this mod 10/10, next best thing i did since 325 Swaybars and Koni's adjustables.

This mod is only the next step once you have your suspension sorted out.

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magic, definitely added to my winter mods list!

Shame you're not in Auckland, I'd love a geez.

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I want to do this but didn't (deadline and all.) I too have added this as a future mod. Looks fairly easy -barely harder than a straight e30 rack swap anyway.

Edited by bravo

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I got a brand new WOF today,

I pointed out my urethane steering spacer, wof man told me replacement urethane is allowed as long as it operates the same as OEM, and does not foul or bind up.

I also pointed out that i had fitted a steering rack from another model of 3 series, and he was quite happy that because it had not been heated cut or welded that it met the criteria.

He went on to explain that as long as its an identical part to the original that all would be fine.

I read up on the rules myself and technically this does require a cert,because its not the exact same part but with a pretty thorough inspection it all came up good, I would put this is the same basket as having a 2.5 motor swap on a 2.0 car legally it requires certified but people actually don't get it done.

I am not looking for a debate here I just with to say that if you do this swap that is it %100 your own responsibility to make sure that YOUR car meets the rules.

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Atm theres not much room between the headers and the steering coupling on my car. Did you notice if the steering coupling had moved towards the engine after replacement? Or did it pretty much stay as is?

Also what is the point of the polyurethane? What else can be used to minimise expense/effort?

I'll definitely be tackling this in the next week as my current rack is starting to really kick up a fuss.

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The new position of the Steering gear is a LOT closer to the Manifold. I would say if you have headers the E36 rack will not fit.

My car runs the Cast Iron M20B20 Face lift single piece manifold for reference.

The poly replaces the rubber in the factory steering linkage, and if you did try to use the factory rubber you would notice the bolt holes do not align up and that it would not be thick enough. The poly is the only suitable replacement that is going to stand up to the twisting,temperature and vibration.

As the poly works like just like the OEM rubber donuts I believe it to be the only thing safe enough.

With the steering of your car you can't really minimize "expense or effort" on this one. Maybe on a sway bar bushing sure but not on the steering shaft.

Its your steering ......

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The new position of the Steering gear is a LOT closer to the Manifold. I would say if you have headers the E36 rack will not fit.

Well that answers that one then. Are there any other racks out there that dont do this? Atm it looks like im "downgrading" to a manual e30 rack.

With the steering of your car you can't really minimize "expense or effort" on this one. Maybe on a sway bar bushing sure but not on the steering shaft.

Its your steering ......

Fair point but im sure theres got to be other ways out there of fashioning that spacer, as it seems to me that spending $110 on a stick of plastic is a bit too much considering the rack costs $100.

When i say minimize i mean reduce cost and effort to a safe point. With your reasoning maximize would have you making the spacer out of solid gold.

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Whats the benefit having an e36 rack over an e30 rack? do they have a better ratio then the manual e30 motorsport racks?

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Whats the benefit having an e36 rack over an e30 rack? do they have a better ratio then the manual e30 motorsport racks?

Yes.... and Z3 racks even better

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Here is another write up/DIY on swopping your e30 rack with an e36 rack. The best write up I have seen on the web. They use a rack swop kit also available on e30tech site, but I think one fasion your own spacers as Im planning to do myself. http://www.e30tech.com/forum/showthread.php?t=21391

Hope this helps

nice write up though, great with the measurements.

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