Correct springs Esprit S1 / S2

[GTK]

A search here didn't bring any up to date info, so I need to pick the collective brain on the right springs for my S2 Esprit. I see some G cars riding high, presumably because they have federal or aftermarket springs. I believe the later cars, from S3 on, had a  ground clearance of 17cm [6.6"], while the S2 is quoted at 14cm [5.5"]. I don't want to correct ride height with adjustable spring mounts or some other trick.

I've been told there's only one correct set of springs for the S2 Esprit, but are proper factory spec S2 springs still out there?

Thanks!

George

 

[drdoom]

There is a formula for calculating rate of a coil spring by way of wire diameter, coil diameter, and number of free coils. Don't have my reference materials for that to hand at the moment, surely easy to find online. Free length completes the spec if one works with a spring manufacturer as I did with great success on my Elan.

Cheers

[peteyg]

Always bought my springs from SJ. Never had a problem as long as the suspension is tightened up with the car correctly weighted as per the manual.

Pete

[GTK]

@peteyg seems like a good excuse for you to post a photo of your car 😁

@drdoom Problem is I don’t have a known standard spring for reference measures.

 

[peteyg]

@GTK Ok then...

[GTK]

As gorgeous as ever Pete, the car too. So off the shelf springs, and which dampers?

[peteyg]

I'm using the Protechs. Had a couple fail and fixed under warranty but I'm happy with them in the main.

[skiing]

I think on the dampers - if you have the originals still (Armstrong) then it is worth having them re-built which I think is possible - (there is a thread on here on this) - I wish I had kept my old ones!

[drdoom]

8 hours ago, skiing said:

I think on the dampers - if you have the originals still (Armstrong) then it is worth having them re-built which I think is possible - (there is a thread on here on this) - I wish I had kept my old ones!

Agreed in regard to the Armstrongs, not overly chuffed with what has been reported on other brands. I was fortunate and wise to have gathered up Konis for my S2 promptly after taking ownership.

Cheers

[GTK]

That’s some lovely intel, I’m all for rebuilding anything that is serviceable.
 

There were Gabriel Red Riders on the front when I got my car, I believe they were cheap but common aftermarket items back in the ‘80’s. So I’m out of luck there. 
 

The rears are something different. They’re not in great nick aesthetically, but seem to work well still. There’s a distinctive shape around the spring seat, and blue paint evident elsewhere. Would be very interested to know if they look familiar…

[drdoom]

Those rears are very likely Armstrong, given the colour, and quite unique dimensionally for the early Esprit. I'd approach the specialists in regard to those. The front are not as distinct, as I found when seeking mine. The vendor was highly accommodating, permitting me to rummage freely in her extensive inventory until I selected a pair which seemed adaptable. Rather a chuckle when they were ID'd as fitment for some vast '70's era American market sized saloon. Fortunately a Koni specialist was located who were equipped to revalve to Esprit spec, while updating the seal to contemporary spec.

Cheers

[EXCEL V8]

The front Armstrong dampers on my Elite looked like that but they measured up perfectly on a damper dynamometer and after some cosmetic attention are now fit for service again:

 

 

Pete

[GTK]

The spring seat looks very similar doesn't it. That's an interesting spring compressor, haven't seen the like of it before.

[skiing]

I have Konis on the front of my S3 and OE lotus ones on the back but I am not sure you can get them any more - I am happy with Konis - I had the pro-techs before and the adjustment knobs fouled on the suspension and where munched... I don't think (from what I read here) that they are very similar in characteristics to the original armstrongs either... I would try and keep / refurb your rears for sure.

[GTK]

I actually bought a used set of Protech shocks as a backup and to compress/extend by hand side by side with my [presumed] original rear Armstrongs, they feel completely different. That said I didn't play with the adjustment knobs. 

Will be checking the old rear for makers marks/part number later today.

[GTK]

 

Just a follow up: my rear dampers are confirmed Armstrong, part number 64 8016. They are not rebuildable. Even the Armstrongs from way back when that are rebuildable can be a hit and miss endeavour because they have some sort of alloy core that degrades. They while they can be rebuilt and brought back to original tolerances, they can start to leak in short order.

For the sake of reference the front Armstrong dampers should have the part number 63 3305 stamped in them. The Armstrong catalogue lists this 64 8016 rear / 63 3305 front damper combination for all M70 Esprits 1975 to 1983. 

If by chance someone sees this and can shed light on my original question, i.e. length of euro spec Esprit S2 springs, especially the fronts, I'd be grateful. I've not been able to find a definitive answer.

George

[rgh0]

Lotus Marques lists the following specifications for S1 and S2 springs.  

 

https://lotusmarques.com/info/technical/30-lotus-esprit/1357-lotus-esprit-s1-s2-road-spring-specifications

[GTK]

Thanks Rohan. I did see that but because Lotus Marques are in Australia I was wondering whether ROW spec cars are the same as Domestic spec or Federal? It could make a big difference.

[Bibs]

@brian_gt4 might know the answer to that one

[rgh0]

Yes the parts manual lists front springs with federal springs as different from domestic / ROW and with an original and replacement spring number for each.  No information provided on why the replacement spring but maybe to do with air con installtion ? Federal springs I presume are about a ride height increase to meet headlight dimension above ground USA regulations

The rear springs are similalry different for Federal versus Domestic / ROW but only one version of each.

I would guess the differences will be in free length only that the springs are set to so you could accomodate with suitable shims if ride to low or with getting the springs free length reset if ride to high.

 

Maybe  Lotus Marques will know more about the differences if they will tell you.

 

cheers

Rohan

 

 

 

[brian_gt4]

Esprit S1 & S2 Springs.  Domestic & ROW springs are common. The Federal cars had different springs.

Front Spring Dom / ROW (D079C4011F) Rate is 21.2 N/mm and Free Length of 355 mm (Fed Front Spring C079C4007F)

Rear Spring Dom / ROW (E079D4033F) Rate is 27.5 N/mm and Free Length of 347 mm (Fed Rear Spring D079D4035)

From memory (45 years ago so a bit hazy!) I think the Federal Cars had the front raised by about 12 mm.

Brian

 

[Bibs]

Legend, thank you Brian

[Fridge]

Good info on the Armstrong rear shocks @GTK

The road springs supplier by SJ Sportcars had Lotus on them when mine were delivered in December 2016 ahead of my Esprit S1 restoration.

As said by a previous poster, the suspension is left untightened until the car is fully built. I had mine  weighed and tracked by a professional and it sits perfectly. Thought it should be noted that the front sat high right up until the windscreen and rear glass was installed.

I know very long term owners of 40+ years who have aftermarket shock absorbers on their car which they auto tested which work very well. On Konis I think.

The Protechs are OK, but I suspect the fronts aren't as good as the originals, but that's only my opinion.

[williamtherebel]

2 hours ago, brian_gt4 said:

Esprit S1 & S2 Springs.  Domestic & ROW springs are common. The Federal cars had different springs.

Front Spring Dom / ROW (D079C4011F) Rate is 21.2 N/mm and Free Length of 355 mm (Fed Front Spring C079C4007F)

Rear Spring Dom / ROW (E079D4033F) Rate is 27.5 N/mm and Free Length of 347 mm (Fed Rear Spring D079D4035)

From memory (45 years ago so a bit hazy!) I think the Federal Cars had the front raised by about 12 mm.

Brian

 

I wish I had seen this when I was having problems with my federal S1 that I had imported into the UK. I couldn't understand why the ride height of my S1 rode so high. After lots of discussion on here I managed to source a 'correct' set of springs (i.e. that lowered the car) from another owner on here. @gvy He also sent me the following vid if you want to check it out.

 

 

[GTK]

@brian_gt4  I love you 💚

For anyone who doesn't know the significance... http://www.lotusespritworld.com/EOtherstuff/MrEsprit.html