Lotus Elan

Front wishbone angles (Again)

PostPost by: richardcox_lotus » Sun Jan 24, 2021 4:25 pm

I was in two minds about whether to add this to the multitude of previous threads on front suspension, but thought better of it, as most of them have been mainly focussed on plus 2s, and this relates to my Sprint.

I’ve been refurbishing (rebushing ; derusting; repacking bearings) my suspension - the first time it’s been looked at in nearly 20 years.

Due to space limitations in my garage, I can only do the work one corner at a time, which I’m quite happy with as it means I have a datum of the existing side during re-assembly.

Having got all components cleaned and painted the suspension is at a higher stance than I would like - the wishbones would not adopt a horizontal position with everything loose. However, they do match the existing - untouched - side ! See photo.

The one item I can’t examine is the spring/shock assembly. They are, I believe Armstrong’s or Koni’s. There are not adjustable, and as the car is only ever used on the road, I have no desire to be playing around with fancy setups.

The car has always driven ok, and been very solid at the front.

Since I took that photo, I still have the suspension loose, and have since loaded it with weight to see if it will settle.

So, has it always been wrong ?
Attachments
F023C3B2-D505-4BD9-A5EE-1EF4BCCE8B24.jpeg and
Richard
'72 Sprint
richardcox_lotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1213
Joined: 11 Jul 2004
Location: Kent

PostPost by: oldelanman » Sun Jan 24, 2021 5:50 pm

Hi Richard,
I don't think you have a problem.
In my experience, when I jack the car up the suspension droops and the bottom of the tyres move closer together so when I lower the car down again friction between tyre and garage floor prevents them moving apart so the car cannot fully settle. Rolling it back and forth a few times normally settles it back down.
Roger
S4 DHC
oldelanman
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1746
Joined: 02 Jan 2008
Location: Dorset UK

PostPost by: h20hamelan » Sun Jan 24, 2021 7:18 pm

As I am often wrong
I believe one only finger tightens A arms etc, gets the car weighted (driver, passenger-if allowed) then torques A arms and suspension. Then get alignment after 100 miles of settling.
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
Love your Mother
Earth
User avatar
h20hamelan
Fourth Gear
Fourth Gear
 
Posts: 900
Joined: 25 Sep 2010
Location: W Kootenay’s B.C.

PostPost by: 661 » Mon Jan 25, 2021 11:16 am

My view only, happy to be corrected.....
The front looks too high. You need to compare the book height to your own allowing for tyre heights, but if the geo is right the wishbones are more horizontal than your picture.
The car may not have settled after lifting, as said, but I think its more than that. As pointed out, if using the original rubber suspension mounts the car needs to be at it's weight bearing height before tightening.
But, I think its more than that. Are your springs too long??
Graeme
S4 SE
S2 GTS
Peterson JPS Exige
User avatar
661
Fourth Gear
Fourth Gear
 
Posts: 920
Joined: 29 Mar 2012
Location: East Sussex

PostPost by: richardcox_lotus » Mon Jan 25, 2021 11:25 am

Yes that’s what I’m wondering... they’ll have been like that for 20 odd years though! :lol:

Can anyone remind me of the expected spring length (from top of dust shield to bottom perch ?

I’ll then take it off again, measure and see what I’ve got.

Regards
Richard.
Richard
'72 Sprint
richardcox_lotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1213
Joined: 11 Jul 2004
Location: Kent

PostPost by: h20hamelan » Mon Jan 25, 2021 6:52 pm

I though I had the post saved, I dont it seems.
Somewhere it mentions 11” and 14”
14 1/4” Not sure on the fraction, but it is 14 ( I suspect this is a touring version for families)
11 3/4” for sporting folk, again, I am sure my fraction is incorrect. I recall almost 3” difference. Look at some picture, you will see some that you could get a fist between the tyre and body, others only a finger maybe two...

Probably the 11” should be a progressive or stiffer spring, and the 14 softer. Hope/bet Foxie knows!
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
Love your Mother
Earth
User avatar
h20hamelan
Fourth Gear
Fourth Gear
 
Posts: 900
Joined: 25 Sep 2010
Location: W Kootenay’s B.C.

PostPost by: Verve » Mon Jan 25, 2021 7:28 pm

I was told by an Elan Expert , that the Factory changed the front shocks to the slightly taller Federal Spec` for all Elans at some point ... hence why you see so many sat a bit higher at the front ( one of mine did ) ... can anyone confirm this ??

I do remember seeing a change in part number in the parts manual ... & my Elan ran lovely with these slightly " taller " original spec` Armstrongs on ... the small increase in ride height was also good for exhaust ground clearance , as well as me getting in & out ; ) !

Naturally , fully laden with 2 passengers the front wheel to body gap will be less obvious ... but we tend to focus on it when nobody is in the car ...

Maybe somebody can confirm ?

Paul .
Verve
Second Gear
Second Gear
 
Posts: 128
Joined: 13 Sep 2003
Location: Retford , Notts., UK .

PostPost by: richardcox_lotus » Sat Jan 30, 2021 7:11 pm

So I’ve started to dismantle the passenger side which has given me an opportunity to check the fitted spring length. It’s coming in at roughly 10 3/4”. I believe fitted length in the manual is 9.8”, so that will probably explain it.

The manual does refer to federal spring availability but i can’t find the length of those to confirm what I have.

Thanks
Richard
Attachments
image0.jpeg and
Richard
'72 Sprint
richardcox_lotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1213
Joined: 11 Jul 2004
Location: Kent

PostPost by: Mazzini » Sat Jan 30, 2021 8:07 pm

Verve wrote:I was told by an Elan Expert , that the Factory changed the front shocks to the slightly taller Federal Spec` for all Elans at some point ... hence why you see so many sat a bit higher at the front ( one of mine did ) ... can anyone confirm this ??

I do remember seeing a change in part number in the parts manual ... & my Elan ran lovely with these slightly " taller " original spec` Armstrongs on ... the small increase in ride height was also good for exhaust ground clearance , as well as me getting in & out ; ) !

Naturally , fully laden with 2 passengers the front wheel to body gap will be less obvious ... but we tend to focus on it when nobody is in the car ...

Maybe somebody can confirm ?

Paul .


Hi Paul,

I believe Federal cars had a slightly longer front springs. It was something to with US headlight height regulations.

In the manner that Lotus operated in the 60's, I can imagine that the US spec springs being fitted to whatever was rolling down the line at the time.

I had a part of NOS federal front springs, sold them to a guy in Gemany.

Cheerio,

Rob
User avatar
Mazzini
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2022
Joined: 11 Dec 2010
Location: NE UK

PostPost by: Craven » Sat Jan 30, 2021 9:04 pm

Your measurement of 10 ¾ is the unloaded length of the shock absorber, nothing to do with the spring, like this the spring is just holding the shock at its fully extended length.
Original Armstrong has a dimension of 1 15/16 inch between the bottom eye and spring platform, it’s the preload and spring rate that will set the ride height.
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1189
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: richardcox_lotus » Sat Jan 30, 2021 10:48 pm

Yes but they give 2 lengths in the manual. A fitted length and an unfitted length.

The one I referred to was the fitted length which I assumed to be when, er, fitted within the collars.

The free length, according to the manual is 16.75inches

So what does fitted length mean then ?

Regards
Richard.
Richard
'72 Sprint
richardcox_lotus
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1213
Joined: 11 Jul 2004
Location: Kent

PostPost by: rgh0 » Sat Jan 30, 2021 11:41 pm

richardcox_lotus wrote:Yes but they give 2 lengths in the manual. A fitted length and an unfitted length.

The one I referred to was the fitted length which I assumed to be when, er, fitted within the collars.

The free length, according to the manual is 16.75inches

So what does fitted length mean then ?

Regards
Richard.


Fitted length is the length when the weight of the car is on the suspension.

cheers
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7814
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: Craven » Sun Jan 31, 2021 12:06 am

Notes on front springs I have:-
Rate 75lb/in
Free length 16.08. Fitted length 9.22 appox 514 lbs preload.

Longer Springs.
Free length 16.75. Fitted length 9.86 appox 516 lbs preload.
Craven
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1189
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: h20hamelan » Sun Jan 31, 2021 12:43 am

anyone have the rear lengths?
Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
Love your Mother
Earth
User avatar
h20hamelan
Fourth Gear
Fourth Gear
 
Posts: 900
Joined: 25 Sep 2010
Location: W Kootenay’s B.C.

PostPost by: h20hamelan » Sun Jan 31, 2021 10:23 pm

Born, and brought home from the hospital (no seat belt (wtf)) in a baby!
Find out where the limits are, and start from there
Love your Mother
Earth
User avatar
h20hamelan
Fourth Gear
Fourth Gear
 
Posts: 900
Joined: 25 Sep 2010
Location: W Kootenay’s B.C.

Total Online:

Users browsing this forum: No registered users and 10 guests