S1 Coil Overs

[My S1]

This is probably an old and exhausted discussion for you folks so I apologize.  I need/would like to replace my coil overs front and rear.  What is the best, fully adjustable brand/model that you guys would recommend?  Also, what are the best spring rates for normal (sure...) public road driving?

[gideon]

I can't say which is best, but I think your options for off-the-shelf adjustable dampers are Protech, Avo, Spax or Gaz.  SJ Sportscars sells Protech.  Lotus Supplies sells AVO.  RD Enterprises sells Spax.  I don't think any of the usual suspects sells Gaz. 

I'm waiting for someone to do a back-to-back comparison and publish their results, but the heat death of the universe might come sooner.  Probably any of the above options would be an upgrade compared to the original equipment.

[BDA]

I got Protech from SJ and I like them a lot. I had old SPAX and while I wouldn’t necessarily blame Spax, they were completely gone. The Protechs transformed my car! They are really too pretty to put under a car. I assume the AVOs are good since everything I’ve gotten from Richard has been good and Lotus Supplies sells them paired with updated springs which might be an advantage for you.

[SwiftDB4]

Second thumbs up for Protech. I run 240/180 # springs, but my S1 is lowered to 40" high. Stock springs are 100/72#. For your use something in between those figures.

[BDA]

I’m running 160/115 and I like that combination really well. I had 250/130 which wasn’t bad but I found it was a bit more tiring on a long trip. Spring length is important too.

[jbcollier]

If you want a smooth ride on normal roads, stick with the stock spring rates and lengths.  I did, and I’m delighted with the ride: swallows most bumps with aplomb.  I very happily run AVOs.  Other dampers would work well, too.

[My S1]

Great advice from all of you guys.  Many thanks.

[Fulvia-hf]

Hello Lotus Europa fans,

I hope I'm allowed to highjack this thread as the title covers my question completely.
I'm the proud owner of a 1968 Europa S1a which slowly but surely comes back together after a lengty and frequently paused restoration.
The car has shed some weight by removing the bumpers and spare tyre, changing out the glass side windows for perspex and fitting an alloy coolant radiator among other things.
I bought the car on very old Koni shocks which I have had refurbished but decided recently that I would rather have ride height adjustable coil-over shocks. I fell a bit in love with Protech suplied by SJ Sportscars. My early car uses the 1.9"ID springs. SJS supplies those dampers however with one spring size only and that is 8.5" by 160Lbs.
Will this spring allow my car to be set to a stock ride height or lower and is the rate good for road use?

Cheers,
W

PS: I plan to replace the front AR bar with a TC item and fit a 1/2" bar at the back.

[Triton]

I have AVO shockers on my Special and i am pleased with them but i think AVO have been taken over by a company called Turbo Technics but still sell shockers as far as i know....

[Rainer]

I do have the protech shocks from SJS.
You can go lower or higher without any problems.
I have only driven about 50 kilometers so far, but the spring rate feels fine to me.

[Clifton]

Hello Lotus Europa fans,

 My early car uses the 1.9"ID springs. SJS supplies those dampers however with one spring size only and that is 8.5" by 160Lbs.
Will this spring allow my car to be set to a stock ride height or lower and is the rate good for road use?

Cheers,
W

PS: I plan to replace the front AR bar with a TC item and fit a 1/2" bar at the back.

A 8.5" spring is not common. Usually even numbers. I run a 1.9" front (Spax though) and the softest spring I have run is a 8" x 250lb and can get the front pretty low.  250lbs was not too stiff in my opinion and only 2hz. Not stiff compared to modern sports cars but compared  to a soft 70's car, yes.

Even with a TC front bar, that 1/2" rear bar may shift that FRC down too much, making the rear carry more weight which will lead to oversteer if the car was neutral. All good until you go off backwards. If you can keep the same FRC and add a read bar, great.  If your FRC is lower than your rear weight bias, it will oversteer. Mine does but for autoX it is good as speed are never above 65mph. For street or a road coarse it is not ideal. If it's a street car, I wouldn't run a rear ARB.

I have a spreadsheet for my car to figure out FRC, front roll couple. I'll try to attach it. My rear suspension is not the same but front is. Weight is for two passengers. My car is more rear weight biased than stock too.

For an S2 bar I got 55lbs, TC bar 135lbs.
Here's a sway bar calculator  https://www.gtsparkplugs.com/Sway-Bar-Calculator.html

[SwiftDB4]

The 160 lb. springs should be good for street use. Are you sure about 8.5" length? I would assume Protech supplies the springs and they list lengths in even inch sizes only. 8" would be good to allow either stock ride height or lower with those shocks. I bought the Protech shocks from SJ without springs and separately bought springs from Protech because I wanted much stiffer ones.

[EuropaTC]

I also have Protech dampers from SJS, but when I got them I was able to specify the spring rates I wanted. Mine's a TC and I ended up with 250lbs front springs and as Clifton says, it's stiff but not outrageous.

Whilst 250lbs compared with 115lbs (or whatever OEM is for an S1) sounds an enormous jump, you've got to remember that it's working at an angle so you don't get the full 250lbs as you would do if it was vertical and acting directly without any suspension leverage. So I'd say that 160lbs will be fine, I doubt you'll notice a massive difference on normal road use.

[Fulvia-hf]

Thanks everybody for their opinion on the 160Lbs springs. I asked Steve of SJC to confirm the 8.5" lenght and he claimes they are exactly that, 8.5".
My car will need to negotiate a 2 mile gravel road before it reaches (often poor) tarmac. I've moved from Holland to central Italy. In holland the roads are perfect but straight. In Italy they are often poor but very very curvy. To keep the fibreglass body crack free an 160lbs spring might be more than stiff enough.

I will try it first with a stock front anti roll bar and no rear bar to see what happens.

Cheers,
william

S1A/1647 crossflow/365 5-speed/47 style wheels.