Author Topic: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q  (Read 5602 times)

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Offline BDA

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #15 on: Tuesday,October 04, 2016, 08:10:58 PM »
Still have drum brakes!?

Which BMW stub axle dd you use?

Offline EuropaTC

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #16 on: Tuesday,October 04, 2016, 10:47:13 PM »
I really like the solution you've arrived at to mount the upper link on the hub carrier, again that's not something I've seen before, every solution I've seen so far has been for the S2 and using a bottom mounted construction which then travels upwards to locate the upper link.

I'm not about to do a conversion on mine but I keep looking about for a 5 speed box and should one come up, I'll probably go that way. I can't see how the S2 solution would work on mine without drilling the carrier and moving the damper mount, which I'm loathe to do. I had thought of welding a bracket on the trailing arm about where the handbrake stop is now, which is almost the same geometry as you've done. So it's encouraging to see someone with experience of that arrangement. 

As you've experience of this arrangement, do you think there's any reason why a welded bracket on the arm wouldn't work as well as your bolted set-up ? I'd be interested in your comments because I think you've solved the inboard mount position in a very neat way. (Yes, I'm going to pinch that idea  :)  )

Brian

Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #17 on: Wednesday,October 05, 2016, 12:39:12 AM »
Still have drum brakes!?

Which BMW stub axle dd you use?

Yes I still have drum brakes on the rear.

The definitive answer for the question "Which BMW stub axle did you use?"
is answered with "I don't know."

About 20 years ago I went to BM Spares in Melbourne with a Hillman Imp stub axle in one hand, and a vernier caliper in the other.
Back then they stripped everything down and put them in big plastic tubs. it was like going to the supermarket.

I picked out a pair of shafts with 30mm bearing surfaces with roughly the same bearing spacings, a flat drive flange, and a drive hub with 4 studs. I think they had 2000 written on them. Maybe a 2000 sedan circa 1970 which pre dated the 1602/2002.

I converted another car a few years later, and I know of 4 other owners that copied my design.

A few years later I bought a pair of 320 shafts for future use, only to find they had 28mm bearing surfaces. Ooops!
A search on the net identified that the 323i used 30mm bearings.

My sketch gives the dimensions of the shafts I used.

Unfortunately these days people don't rebuild BMW's. They drive them til they die, then sell them for scrap.

I am always on the look out for the next stub axle to suit my conversion.





Offline BDA

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #18 on: Wednesday,October 05, 2016, 05:38:00 AM »
Hmm... That.will make it harder. I think (hope) that the weaknesses of the rear corners of the S2 were solved on the TC but I know that stub axles are not hardened and that concerns me. Maybe it would be a good idea to join some BMW forums and ask around.

Online andy harwood

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #19 on: Wednesday,October 05, 2016, 07:30:16 AM »
Richard -
Thanks for writing your conversion up! I have printed all I could find on the yahoo group. I'm going to be using your idea in the near future.

"I am always on the look out for the next stub axle to suit my conversion"
One conversion on the Yahoo group used VW beetle stub axles, and axles. Did you read of this conversion? If so, what did you think of it?

Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #20 on: Wednesday,October 05, 2016, 02:48:11 PM »
Richard -
Thanks for writing your conversion up! I have printed all I could find on the yahoo group. I'm going to be using your idea in the near future.

"I am always on the look out for the next stub axle to suit my conversion"
One conversion on the Yahoo group used VW beetle stub axles, and axles. Did you read of this conversion? If so, what did you think of it?

I haven't read the VW conversion, but I am already onto it!! It is the next idea I will explore. See attached exploded view. The stub axles and drive flange are perfect donors, as long as they measure up!

I've also attached a screen dump of a 2002 Turbo exploded parts view. 2002 Turbos don't exist in Australia, so the stub axle must have come from a high volume donor vehicle. The Turbo parts looks very familiar because it has 12 holes in the drive flange.

More BMW pictures attached. The stub axle has a 24mm thread on the end - the Hillman Imp has 3/4" UNF which is 19mm, so the BMW one grabbed my attention because I knew it could withstand a much higher torque and apply a bigger clamping load to the bearings, hub and spacers.


Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #21 on: Wednesday,October 05, 2016, 02:49:36 PM »
Missed the Turbo picture. here it is

Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #22 on: Wednesday,October 05, 2016, 03:00:47 PM »
And some more to keep you distracted from work, household chores etc.

I made these engine mounts in 2005 with only one aim in mind - TO STOP THE ENGINE ROLLING AROUND A LETTING THE REAR SUSPENSION MOVE.

I had many failures with the old shear mounts due to poor quality manufacture. These mounts transmit more vibration, but make a considerable difference to the cars handling.

I'm currently rebuilding an S2 Elan and note the Tony Thompson Racing offer similar mounts.

The last picture was taken by a guy with a Subaru Forester that had been lowered and tweaked. He loved my car so much he photo-shopped it and sent me this picture.  :coolpic:

The Europa attracts more attention than any other car I've ever driven.

Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #23 on: Wednesday,October 05, 2016, 03:11:52 PM »

As you've experience of this arrangement, do you think there's any reason why a welded bracket on the arm wouldn't work as well as your bolted set-up ? I'd be interested in your comments because I think you've solved the inboard mount position in a very neat way. (Yes, I'm going to pinch that idea  :)  )

Brian
[/quote ]


I like to do modifications that are easily reversible.
Sometimes they don't work.
Sometime in the future someone may want to convert the car back to original.

You may have noted that I removed the rear hoop from the chassis to incorporate my 5 speed conversion. I carefully cut the original cross member off in such a way that it could be welded back in. 

So I am always mindful of how I modify something. I try and make it reversible and I try and make it simple/cheap.

The outer bracket is bolted because I didn't know if it would work. The bracket started life as a bit of 4"x4"x1/8" square tube. It looks ugly to me, but it is effective!

Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #24 on: Wednesday,October 05, 2016, 03:22:42 PM »
Richard,
I'm very interested in seeing the CV drive flange.  I'm going to running VW Golf shafts on my car and I've picked up a set of 100mm inner flanges from a VW gearbox, but I'm undecided on the way to adapt them.  Did you machine up a complete output shaft, or did you cut and weld the Lotus (or Renault) output shaft to the Alfa output shaft/flange?


Rod


The flange is a piece of 1/4" steel plate - nothing fancy. It is welded to a female spline that came from a donor Renault drive shaft, so if you find some old dead Renaults take the drive shafts so you can use the end spline.

The following cars use the same spline - R12, R15, R16, R17, R18, Fuego. Maybe the R20 with the 1647 engine.

I'll find photos, or take photos .

Lastly these cars all use 6mm roll pins, and the Europa uses 7mm roll pins with another smaller one inside.

I haven't use roll pins for about 20 years. I use a 7mm bolt.



Offline Lotus 47

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #25 on: Wednesday,October 05, 2016, 03:34:05 PM »
2 - the bolt heads are on the outside, because the trailing arm is VERY close to the chassis, and there is not enough room for a nut and washer




Not particularly clear photos but you can see how close my trailing arm is to the chassis, dictating bolt heads to the outside!

Offline RoddyMac

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #26 on: Wednesday,October 05, 2016, 03:46:14 PM »
Quote
The flange is a piece of 1/4" steel plate - nothing fancy. It is welded to a female spline that came from a donor Renault drive shaft, so if you find some old dead Renaults take the drive shafts so you can use the end spline.

Thanks for the info, that was going to be my original plan of attack with just machining a plate, but I've changed course slightly by obtaining the VW flanges.  I'm planning on turning down the Renault CV and boring the VW flange to have a slight interference fit, then weld them together.   Now I just need to find another dead Renault CV axle, the gearbox i picked up had the remains of one.  I wish it had two.

Rod

Offline BDA

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #27 on: Wednesday,October 05, 2016, 04:18:55 PM »
Thanks for the extra photos, Richard! Your trailing arm is much closer to the frame than on my TCS!

Offline GavinT

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #28 on: Wednesday,October 05, 2016, 05:47:29 PM »
A fellow Europa owner lost his LH rear wheel on the track, probably as a result of constantly applying high torques to his LH stub axle nut, to the point where the end of the stub axle and nut disappeared into the weeds, while his whee,l brake drum and drive flange shot off and hopefully didn't hit anything.

Oooops . . that was probably me.
Hi Richard.  :)

Offline EuropaTC

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Re: RICHARD MANN'S UPPER LINK AND REAR SUSPENSION MODS TO 7004100119Q
« Reply #29 on: Thursday,October 06, 2016, 12:11:35 AM »

I like to do modifications that are easily reversible.
Sometimes they don't work.
Sometime in the future someone may want to convert the car back to original.

You may have noted that I removed the rear hoop from the chassis to incorporate my 5 speed conversion. I carefully cut the original cross member off in such a way that it could be welded back in. 

So I am always mindful of how I modify something. I try and make it reversible and I try and make it simple/cheap.

The outer bracket is bolted because I didn't know if it would work. The bracket started life as a bit of 4"x4"x1/8" square tube. It looks ugly to me, but it is effective!

Thanks for coming back, I understand your reasoning, it's always good not to burn too many bridges.

"simple/cheap" works for me as well !   :)

Brian