Rear uprights

[wobblyweb]

Hi all,
I need a rear upright for my Sprint. Are +2 and Elan uprights the same? (issue 18)
I believe the wheel hub is different but could the Elan parts be fitted to +2 uprights

Would like to buy 2 used uprights and +2 seem to be more readily available?
Thank you

[draenog]

As nobody else has replied... By rear upright I assume you mean the damper/bearing housing? My understanding is that the later ones are the same on the Elan and +2. The easiest way to confirm is to look at the part numbers in the parts lists:

Elan: https://lotuselan.net/wiki/DA_-_Rear_Suspension (item 15)
+2: https://lotuselan.net/wiki/DA_-_Rear_Suspension_%2B2 (item 19)

From this you can see that from chassis No. 7762, the Elan parts have a +2 part number (050D6003/050D6004), which matches the +2 parts list.

[wobblyweb]

Thank you for the info, it helps with my search.

[andyelan]

Hi there

Just to clarify a bit more. While the basic legs are the same, once they're built up into assemblies with dampers, hubs etc. they're no longer interchangeable. So you can't take s/h Plus 2 leg and fit it straight to a two seat Elan as is. It will need to be rebuilt first with the appropriate parts.

Regards
Andy

[alan.barker]

I think you only need to change the Hub for Elan Hub that's all.
Alan

[andyelan]

Hi there

Damper settings, either built into the leg itself or as separate inserts, needs to be stiffer for the Plus 2 compared to the Elan. If it's not, then the rear suspension will be much too soft.

Regards
Andy

[alan.barker]

As far as i know original Armstrong Inserts were the same. Rate of Oil transfer inside Damper both models the same.
For me the difference between Elan and +2 is Spring rate for the 200 kgs difference in car weights.
Unless you have different info.
Alan

[andyelan]

Hi Alan

According to the Lotus Plus 2 parts book the bare leg has a prefix "26" part number which identifies it as an Elan part, however, once it's built up with a damper the assembly becomes a prefix "50" which applies to the Plus 2. There is also a separate damper listed which is also a prefix "50" i.e. Plus 2 part.

I agree that there are Armstrong inserts that did state they were suitable for the Elan and the Plus 2 but I don't think that was what the engineers at Lotus ever intended. My own thoughts are that supplying just one insert suitable for both cars was simply a cost cutting exercise on the part of Armstrong.

What I do know is I tried a several damper inserts, including a set of NOS Armstrongs on my Plus 2 and could never get it to handle properly as it was always way to soft at the back end. I finally fitted a set of TTR inserts which they specifically list as for the Plus 2 and I couldn't believe the difference they made. The transformation was remarkable.

Don't forget that for Chapman it was always the damping rather than spring rate that mattered.

Regards
Andy

[alan.barker]

Thanks Andy,
Good info.
I think it changed to a 50ref when they changed the Inner Bearing to a wider one.
Soo many changes it's difficult to be sure.
Alan
Just looked at sjsports same Shock Insert.
For me Elan or Elan +2 are the same part.

[andyelan]

Hi Alan

Sorry, but I beg to differ. I appreciate inserts are sold as being suitable for both the Elan and the Plus 2 but, speaking from personal experience, I think it's wrong. It's possibly done simply to keep inventory and costs down rather than because they're right for the car and that's by manufactures not necessarily suppliers

TTR (to whom I've no connection) supply inserts specifically valved to suit the Plus 2 and using these was like the difference between night from day.

Sorry to disagree
Andy

[alan.barker]

Hi Andy,
No problem. What you say is better logic
With 200kgs difference.
I agree with you maybe different and nothing noted down by Lotus.
Alan