Spyder Double Wishbone Rear on +2

[vincereynard]

I've been offered a +2 with a recent spyder RSC rear suspension.

"Optimised for modern low profile tyres" allegedly.

With the top wishbone being considerably shorter than the bottom this suggests to me limiting the camber change by limiting the suspension travel. Which may not be a positive on Buckinghamshire's potholed horrors.

I've driven a full on Zetec and that was too solid for my preference, but it could have been just that one.

Anyone done the conversion and can give an opinion on the ride before and after?

Attached image is a bit poor but seems to indicate that the top wishbone outer bearing is a rose joint. That cannot be good for NVH!

Cheers
Vince

[RonR]

I'm afraid I can't help you with questions about the ride, as my car hasn't turned a wheel since fitting the RSC kit.
However it appears that Spyder have produced 2 versions of the upper wishbone, as my top wishbones have a rubber bush at the outer end:

Spyder RSC outer bush

I suspect the rose jointed ones are meant for competition.

[rgh0]

The fundamental design is OK and the top to bottom arms length difference not excessive ( but not the best either). However the design is let down by detail issues and is no real improvement on the original Chapman strut as far as i can tell

In particular the spring diameter is too small for its length leading to instability which will result in it buckling and rubbing on the shock.

cheers
Rohan

[Gray]

Again, my S4 has not been used since the conversion. I spoke to someone some years ago at a Club Lotus meeting who had converted a Plus 2 to the Spyder double wishbone system and he thought the ride was much better, it will obviously be dependent upon springs and damper settings.
One of the reasons I went this route was to prevent the positive camber under hard braking that is inherent on the original strut. Late braking into a corner can cause a spin with positive camber, not that Elans are particularly prone to this, but it can happen! The Spyder system goes back to negative camber at full suspension droop due to the shorter top arm.
I've not noticed spring buckling on any I've looked at, I believe the spring/damper unit is based on the Europa rear assembly.

Cheers Gray

[rgh0]

You can see the spring buckling in the first post photo

Under hard braking the issue is more about bump steer and toe out on the front rather than rear camber change

regards
Rohan

[vincereynard]

Thanks for the replies chaps.

I have noticed buckled / bent springs on several front suspension with the narrow springs so I suppose the same being a possibility at the rear is no surprise. I imagine that after the spring starts to bend the rate goes anywhere, depending on if it is contacting the damper body.

It must be a known characteristic, so why don't the makers just fit bigger diameter springs if the solution is so easy? Or is it the same old fitting fat low profiles again?

Under hard braking the issue is more about bump steer and toe out on the front rather than rear camber change
regards
Rohan

I thought it was misalignment of the rear wheels causing excess toe out that caused it to be a bit frisky.

Actually if hard braking into a corner was precipitated by it tightening up a bit of rear wheel slide could be a bit handy.

[Spyder fan]

I've been offered a +2 with a recent spyder RSC rear suspension.

"Optimised for modern low profile tyres" allegedly.

With the top wishbone being considerably shorter than the bottom this suggests to me limiting the camber change by limiting the suspension travel. Which may not be a positive on Buckinghamshire's potholed horrors.

I've driven a full on Zetec and that was too solid for my preference, but it could have been just that one.

Anyone done the conversion and can give an opinion on the ride before and after?

Attached image is a bit poor but seems to indicate that the top wishbone outer bearing is a rose joint. That cannot be good for NVH!

Cheers
Vince

If you look at my Spyder Zetec owners topic you will see it's not really a good idea to go low profile if you want to avoid the "off road" look . with 14 inch wheels you need 65 profile to get the right diameter and not the 60 or even 55 profile I have seen on some +2's. Of course you could go up to 15 inch wheels and have lower profile rubber, but you lose something of the look of the car if you do that. http://www.lotuselan.net/forums/elan-mods-f31/spyder-zetec-owners-elan-net-t34406.html

My +2 is certainly not harsh and I have the rose jointed upper bearings. The problem with before and after comparisons is that almost certainly you are comparing worn out components with new albeit different components. I remember thinking the whole car felt tauter and that the suspension was firmer but better damped. Hardly a scientific comparison when it's worn stuff versus new stuff.

Here is an extract from Spyder's web site. The first paragraph is what you refer to and one I don't see the point of unless you can lower the car without grounding out!

Lotus Elan & +2 Spyder Twin Wishbone Rear Suspension System (RSC)

Our sophisticated rear suspension conversion offers remarkable improvements in reliability, handling and road holding. It takes full advantage of the latest tyre technology, exploiting lower aspect ratio tyres to the optimum.



Irritants such as leaking rear struts, perished bump rubbers and broken circlip grooves in the bearing housings are a thing of the past. The rubber drive couplings have an easier life too, as rear wheel travel has been reduced to 6?. The RSC also overcomes the difficulty of finding those obsolete or obsolescent rear end parts such as strut tubes, alloy hub carriers, upper spring seats etc. The lotocones ? items which, more often than not, are supplied nowadays with non-original and incorrect tapered inner sleeves ? are replaced by simple rubber bushings in the upper ends of the spring damper units.



The RSC is easy to install and uses bushings, bearings and dampers already common to other Lotus cars.

[denicholls2]

Here is an extract from Spyder's web site. The first paragraph is what you refer to and one I don't see the point of unless you can lower the car without grounding out!

I think the point is to employ tires of the same final diameter but with lower aspect ratio by using larger rims. Against a possibility we're already seeing of older aspect ratios becoming much harder to acquire. Some also do want to lower the car, but off-track there's little wisdom in that.

Millennials seem to think this looks fabulous, and to the extent the added rim material is lighter than the removed rubber material it's a functional improvement, but I agree with the above sentiments that you can make a pretty car look hideous with tall rims. In fact, the biggest downside I see of this approach is that few cars, even modern ones, don't look hideous with them. (By the way, I think we need a tongue-sticking out "yuck" Smily.)

[Gray]

One of the main reasons for the Spyder RSC is to be able fit 6x14 wheels so that there is a much wider choice of tyres available. Lotocones were also unavailable when I bought mine. Clearance is still a problem on an Elan between the wheels and body in many cases, hence my change to 26R arches. Plus 2 wheel to body clearance is OK as far as I'm aware. Since this conversion became available (over 20 years ago) strut conversions to allow narrower springs and wider wheels have also become available.

Rohan - I agree the original photo shows a distorted spring. This is a fairly common issue with narrow spring damper units, although I've not noticed on a Spyder RSC before. Is it much of an problem? There might be a little bit of friction between the spring an the damper but I can't imagine its going to affect the overall characteristics much. If it is a problem can alternative spring construction (wire thickness/windings) help, or is it something we just have to live with?

Cheers Gray