Lotus Damper Programme
Lotus Engineering sets about redefining the Esprit Suspension for 2006
Lotus' Spring & Damper Programme was started in mid 2005 and covers Esprits from 1987 to 2004. Lotusl tested and set-up each Esprit model (turbo, SE, S4, S4s, GT3 & V8) with new springs and dampers doing a baseline appraisal on the current parts before they began the development exercise. Also see the development of the Poly Bushes here.
Lotus Ride & Handling Engineers then fitted special springs and dampers for development. Lotus looked to create new specifications based on the old set-up, but refining it. With the advancement in modern materials and design, they have developed a suspension package for the Esprit models of the past using today's know how.
Lotus have created new spings & dampers for each model retaining the 'feel' of each model, but improving the ride & handling without making all the models feel the same. Lotus have taken this project seriously and have investing a lot of money in it's development. The development has being done on both track and road and covers many different types of road surface, including motorway, A-roads, B-roads and the varying surfaces these can have. As you should know, Lotus is one of the leading companies in Ride & Handling and have years of experience in setting up road and track cars.
Once the programme had finished, Lotus had all the data for the springs and dampers. They then decided on how many kits need to be produced to cover the models. Dampers will be manufactured by Bilstein and are to have dual platforms, so the ride height can be lowered 10mm from standard. Adjustables would have worked out too expensive and with all the work done by Lotus, you won't need to adjust them.
Springs will be manufactured by Eibach and will fit both the Bilstein dampers and the standard Lotus dampers. Meaning you'll be able to fit just the springs to your Esprit or the whole package. Lotus are working on fitting them to 1983-1985 Esprits as well. So nearly all models will be covered.
LEW has been helping with the development of the suspension and has been impress by the amount of work being done for what is basically an out-of-production vehicle. Our view is this is going to be the best upgrade you can buy for your Esprit. Developed by Lotus, in a field they are renound for worldwide, for their own cars and using the lastest materials and technology. The Esprit is hard on it's suspension so many older cars with average mileage will be running on original suspension, which is probably well worn. Upgrading to the new spec, would not only give the improvement of fitting new standard kit, but with the newly developed spec you should see a massive change in ride and handling. We know, we've tested it!
More information will be posted here as it's released. The price should be reasonable on it's release, which we hope to be well before the years end.
A very exciting development.
Update Feb 2006
Pricing on New V8 dampers
We have now got some Retail Prices for the new Bilstein Dampers. The V8 Dampers are going to Retail at £247.50 + vat per pair (Front & Rear). This compares with the Current V8 / S4 / S4s Damper Retail Prices of about £ 150 + vat each for Fronts & £100 + vat each for Rears. For the Sport 350 the current Retail Price is about £385 + vat each for Fronts & Rears.
As a simple comparison :-
The new Retail Price of about £250 per pair compares favourably with the Current Dampers.
Current Damper (V8 / S4 / S4s) about £500 per car set
Current Damper S350 about £1540 per car set
New Bilstein Damper about £500 per car set
These are not yet available to purchase, this is just a release of the price of the V8 dampers only. More information will appear here as we get it and we will announce when it's available to order. As fair as price goes, it's looking like Lotus have taken note to what owners are after and are willing to pay. Bilstein Dampers at this price, with specs by Lotus Engineers! We must be dreaming.
Update April 2006
Lotus' Spring & Damper Programme
The Esprit Damper Project development phase is complete. The prime object of the exercise was to find a new source of dampers to replace the obsolete components from the original supplier. The manufacturing plant that produced the damper components is no longer in operation.
A new supplier (Bilstein) was found and they agreed to a programme to produce a range of dampers to suit the Esprit. It was decided to take the opportunity to evaluate all the Esprit variants and revise the damper settings to produce a slightly 'sportier' feel to the car (following consultation with vehicle owners).
Looking back over the currently specified components there was over 20 front dampers and 20 rear dampers specified, most of which had been superseded over time and now all obsolete. On the Springs there was over 30 front springs and 20 rear springs released many of which were obsolete or superseded.
It was decided to retain the currently specified spring rates but specify new springs to a more up to date material specification. To evaluate and revise the Spring rates would require a much more comprehensive (longer and more expensive) development programme that was considered unnecessary. The new Dampers and Springs are being manufactured at the moment and we expect delivery at any time.
On delivery the necessary quality checks will be carried out to ensure the components are to the agreed specification. All the variants of the components will also be checked on vehicles to ensure parts are performing as per the development units. The parts will then be released to the Aftersales Group for distribution to the Dealer Network.
Lotus will not be releasing the technical specifications of the new components (which is no different to current practice). This information would allow a third party to reproduce the component characteristics with no development costs. Lotus Cars has invested tens of thousands of pounds in this exercise so the information is extremely valuable.
The change in vehicle damper specifications has been developed and specified by the Lotus Ride & Handling Engineers who decided on what revisions were considered necessary to produce the desired vehicle characteristics. This development exercise was to produce a new 'Road' specification and not a specific track / handling package. These components are to replace obsolete production components so need to satisfy the needs of all Esprit owners. No changes have been made to the Anti Roll Bar or Suspension Bushes. No Suspension Geometry or Tyre Pressure changes have been made – they remain as per the Lotus Service Book specifications.
We were very lucky to get the opportunity to have a chance to revise the damper settings. The simplest and cheapest option would have been to reproduce the current tested and approved damper settings. We must remember that the vehicle has been out of production for over two years - not many manufacturers do development exercises on out of production vehicles.
The 'Stock' V8 spring rates are Front 250 & Rear 275. The New Springs will be to the same specification for that model. The increased rates of the Sport 350 will be retained for that model (Front 350 & Rear 330). The Final Edition Suspension Package remains unchanged. This is already a Bilstein / Eibach package.
The object of the exercise was to retain the existing characteristics of each model. We could have made everything feel and handle like a Sport 350. This was not an exercise to produce a 'Track' suspension package. Just as much development went into producing an acceptable 'Ride' specification as the 'Handling' part.
We are talking about producing components for road cars not track cars. Considering that the current components are obsolete and are no longer available our first consideration must be to find suitable alternatives for these components that satisfy the needs of most owners. We have not gone out to produce a vehicle that is x seconds faster round our test track.
Update August 2006
Lotus' Spring & Damper Programme
Lotus have finally taken delivery of most of the springs and dampers from Blisten and Eibach for the different models and have been fitted to Lotus's Turbo Esprit and will be assessed next week by ride and handling. The V8 is next and then client cars, which
they expect to turn round in 2 days per car. Once all the vehicles have been fitted and checked, the suspension will be available from your local Lotus Dealer (give or take some paperwork!). As you can see from above, the dampers are looking a lot better than the previous dampers. Of course they'll also perform much better too!
As soon as more information is available, you'll hear it here first. LEW's Esprit will be fitted soon with the suspension, so we'll also be able to give you a review of the quality and performance. This is an important launch for Esprit owners, as with the Esprit out of production, you wouldn't expect new updated component from the manufacturer. If we support this project, we may be lucky enough to get more components made for our cars.
Above are two pictures of Lotus's Esprit HC turbo fitted with the new springs and dampers. The pictures were taken at mid laden weight, (2 occupants, fuel tanks half full) the ride height has been set 12 mm lower than production spec, Lotus do not recommend setting the ride height any lower for road use.
Esprit Owner Update
by Alan Tong, Esprit S4s
Yesterday I visited the factory to collect my S4s complete with the new Ebach springs and Bilstein dampers. Having now emptied a full tank of fuel trying them out :-) its time to report on my first impressions.
First of all some background, as part of the development program Lotus wanted to ensure that they had baseline to compare to. To do this they fitted my car initially with brand new suspension of the original design (ie springs and dampers that were effectively designed 30 years ago) and set the car up exactly as the day it left the factory. This was a few months ago and to be honest it was a revelation. When the Esprit is set up (by experts) exactly as it left the factory it is truly superb. Like most owners my suspension was a few years old (the original suspension wears very quickly) and had not been set up properly. I can not stress enough how important this is - the Esprit suspension is very sensitive to alignment / setup and unless its done properly, whilst its still good it does not hit the sweet spot. As an example before any alignment work is done the car should be loaded up with weights to simulate the weight of a driver, passenger and half a tank of fuel. When I have had any suspension / wheel alignment done in the past (other than at Lotus...) this was not done and as a result the alignment was wrong.
Anyway, the reason for explaining the above is to highlight that when I got my car back yesterday I was comparing the new suspension to "old" suspension that was working and setup perfectly. What I had expected is that the new suspension would be very similar to the old, but due to the more modern design would stay within that sweet spot of superb handling for much longer - hopefully years.
I am pleased to say that the new suspension was much better than I expected, so far I have only been able to drive on the road not try the absolute limits but this is what I have found so far....
The first thing I noticed is the ride quality, its much smoother and soaks up the minor variations in the road better. I live at the end of a track about 1/2 mile long which is not very smooth, this stops me getting up much of a speed as the car bounces around too much (on one side there is a river, and the other a drainage ditch...). With the new suspension it honestly felt like someone had resurfaced the road. Dont worry that they have just made the suspension softer, its not when you push through a bend, nor has it lost the feel and feedback through the steering - you can still feel for example when you have driven over a small pebble on the road. Its difficult to explain - it just soaks up small variations in the road better.
Probably related to the above, on the way to work I have to stop at a t junction where the road has a couple of big pot holes. This always caught out the ABS as I go over the pot holes 9 time out of 10 the ABS cuts in just when you dont want / need it. This morning the ABS did not cut in so I turned round and tried again - it still did not kick in.
At high speeds, changes in direction seem more stable. In tight bends the suspension actually feels stiffer than the old and gives more confidence. Somehow they have made the suspension more sporty when you want it, yet the car has less noise / vibration when just running along a normal road. For me this makes the car better as a daily driver, it handles better when you want some fun yet is less tiring to drive over long distances. This to pretty neat trick and shows firstly what a good job they have done and secondly how much spring / damper technology has improved over the years.
I guess the real question is should you buy the new suspension. If you need to replace your suspension then the question is a no brainer - the new Lotus suspension is about the same price as the old suspension and having seen the work Lotus have put into the development program you are kidding yourself that aftermarket suspension is going to be as good. Lotus do know a thing or two about suspension....
What if your suspension is OK, is it worth upgrading? This is a more difficult question to answer and I think it depends on whether you plan to keep the car for a few years. My argument is that the old suspension does not last for many years, whilst the new being of a modern design will last much longer. For this reason if you are planning on keeping your car for a few years then the chances are that you will have to change the suspension anyway, surely it makes sense to do this sooner rather than later as you will then have full benefit from the improved suspension which should last for many years. Bear in mind most of us are driving around on slightly worn suspension that is not set up properly, the change you will experience going to the new suspension will be even MORE impressive than I have noticed.
If you do go for the new suspension then please think carefully about who is going to fit it for you - once again I can not stress enough that it needs to be set up by someone who knows what they are doing otherwise the benefits will not be seen. One thing I have not mentioned in this rambling post is that the new suspension has two options for height, I have set mine to the standard height, I think the other setting is 15mm lower (need to check this).
I will be at the factory day on Monday so will have put on a few more miles by then, if anyone wants to look at the new suspension (the yellow colour of the dampers looks good if your car is norfold mustard!) or drive it around to see how it feels (if practical) then let me know on the day.
Lotus Suspension Update
Lotus Cars are pleased to advise that following intensive engineering development work, new Bilstein dampers and Eibach springs will soon be available for your Esprit. Damper development is concluded, please find below the details. These dampers can be
used with your existing springs.
Work on the Eibach springs is due to be concluded later this month. All springs and dampers are supplied in pairs (not assembled as springs/dampers) prices shown are also per pair.
All are available with the exception of Sport 350/300 springs, ( 6 weeks delay) for these two variants clients will have no option but to buy springs and dampers for their initially requirements, new dampers will not fit with old springs.
The New Springs & Dampers (like all other Lotus parts & accessories) are available through any Lotus Dealer worldwide.
The Lotus Web site (www.lotuscars.co.uk) has a Worldwide Dealer Locator that identifies the approved Lotus outlets.
The New Dampers are now in stock for both V8 and 4 Cyl. cars.
The New Springs are available for most cars from 1985 onwards (except for Sport 300 & Sport 350 which we are still awaiting).
Not every variant of spring is available on the new list but we have information on what can be used in its place. (It would be impossible to find a supplier to produce new springs for every variant as quantities are so small) The New Dampers can be used with the old springs. The only thing that is needed is a different rear spring platform and Lotus can supply them if needed.
Lotus Suspension fitted to LEW's Esprit
Review coming soon
The New Springs & Dampers have just been fitted to LEW's Esprit by Lotus Engineering. We will be retrieving our Esprit next week in time for the ClubLotus Parts Fair at Stoneleigh. Once we've done a few miles, we'll be reviewing the new stuff to see if it's worth spending your hard earnt cash on. From what we've heard so far, from other owners who took part in the testing, it's makes an amazing difference. We look forward to finding out.
The Esprits ride height should be checked at this time, or any time when suspension work is done. The ride height is critical on the Esprit for good handling. The ride hight should be 170mm front and rear and should be within 5mm either way. If it's not, you have a problem that needs looking into. If everything is correct with your car, the ride height will fall within this tolerance.
To measure the right height you need half a tank of fuel in the car at the time of testing. Then you need two people weighting around 75kg (about 11.5 stone) each or 150 kg in total sitting in the car on a flat even surface. You then measure from the ground up to the chassis. This can be done at the front on the box section and at the rear at the bottom of the cradle.
If you fall below 165mm or above 175mm front or rear, you need to check all the suspension componants. Springs and dampers would be worn beyond acceptable limits, or you could have damage to the suspension mountings.
Below is the official stuff from Lotus
Suspension geometry adjustments.
Under normal service conditions, the only period scheduled check necessary is of the front wheel alignment. A full geometry check is required only after front suspension repair, or if any excessive tyre wear is evident, or if steering difficulties are encountered. Before any measurement or adjustments are made it is essential first to set the vehicle to it's "mid laden" ride height, approximating to driver and passenger (2x 75kg) and fuel tanks half full.
The mid laden ride height for the majority of the Esprit variants is 170 mm + or - 5.0 mm front and rear at production release. There are some exceptions, so please check owners handbook for geometry data. Some owners have none standard springs, increased their vehicle weight with accessories and some reducing their vehicle weight, the fitting of different engines, transmissions, wheels/tyres will have a bearing on "mid laden" ride height.
The dimension should be recorded below the chassis front section L&R and below the chassis rear loop. Replaced suspension components prior to geometry check should be left relaxed, steered wheels straight ahead, then secured at "mid laden" weight to specified torque. This practice is recommended to prevent pre-stressing and accelerated wear of the rubber bushes resulting in deterioration of the handling.
ESPRIT SPRINGS AND DAMPERS
Parts bulletin released to Lotus Dealers, Nov 06
Lotus is pleased to announce that a comprehensive development programme between Lotus, Bilstein and Eibach, has resulted in a rationalised range of road springs and dampers now being available for Esprit models from 1985 onwards. The new Bilstein dampers are supplied only in axle pairs, and are complete with eye bushes, removable lower spring seats and spindle dust cover.
It is recommended that for optimum dynamic performance and balance, the new dampers are fitted in complete vehicle sets. The spring seats supplied with the dampers are tailored to the new Eibach spring internal diameter of 81mm. If the original 76mm i/d rear springs are to be fitted on the new dampers, new 76mm seats may be ordered in addition, under part number LOTAC05449.
* All dampers and springs are supplied in pairs.
* Good quality spring compressor clamps are required for spring/damper assembly.
* Recommended to fit as complete vehicle set.
* If retaining old rear springs, order in addition modified spring lower seat LOTAC05449 (supplied singly).
* Damper bodies are machined with two grooves for the lower spring seat circlip. Use the top groove for standard ride height.
* Fit the dust shield to the damper before assembling the spring and (original) top plate.
* Where tapered front springs are used, the smaller diameter is uppermost.
Suspension Work Continues at Hethel
Lotus working on Suspension for Giugiaro Esprits (January 2007)
Lotus Engineering currently has an Esprit S1 at Hethel for Damper work. Bilstein are producing new Dampers for this variant for Engineering to test. The S1 & S2 have different Damper Mountings that require revised Dampers. Lotus are awaiting the prototypes at the moment.
Lotus Engineering will also been doing the 1980 – 1985 Esprits in the future. No timescale is currently available for this, so don't waste yours and Lotus's time enquiring about it. You WILL hear about it here. As soon as it's available Lotus and LEW will let you know, as Lotus WILL want to sell it to you.
Good times ahead in 2007 with Lotus continuing to support Esprit owners!
Update from Lotus Cars
Suspension work continues!
28th February 2007
At the moment Lotus are awaiting Bilstein Dampers for the Esprit S1 for testing. Bilstein are at Lotus on 1st March, so they will know how things are going. The S1 & S2 have different damper mountings at both Front & Rear compared to all other cars.
The Springs for the Sport 350 are made and the first set is on the way to Hethel for approval. Lotus should have a Sport 350 there in a couple of weeks time. Hopefully all will be ok and they can release the Springs & Dampers for that model. The 350 has completely different Springs and Dampers. This means that new springs are required to fit the new Bilstein Damper - the old springs can't be used. The Sport 350 (& Sport 300) used the Monroe N65 Damper and not the N63 like the other cars.
Lotus still have to do a check of the front damper on a car from the 1980 – 1985 range. They need to check the damper body clearance with the lower link. As soon as they get a chance to do this Lotus will have covered the bulk of cars built from 1980. If the S1 & S2 work goes well they should be able to cover nearly every Esprit built.
Lotus are also working on Suspension Bushes for the 'Early Cars'. Lotus Aftersales Group have not stocked some of these parts for a long time. Lotus are also looking into remanufacturing the lower rear links for the S1& S2 and the S3 cars with Compomotive wheels to take the more modern bushes including the 'Poly'. All the bushes for these models are currently obsolete.
On the Suspension links things will only happen if there is any interest in owners wanting the links. Getting the Genuine (correct size and stiffness) bushes for the old links is now extremely difficult (and expensive). It would make more sense to change the links to use the new type bushes where possible.
Lotus are looking to get some feedback from owners of S1 & S2 cars with the original links. Email email@example.com
There is also a special link for the Early Turbo Cars fitted with Compomotive wheels. We can make a revised link for these if there is
Update from Lotus Cars
Suspension work completed for post 84 Esprits!
Lotus have just finished the final Spring & Damper work for the later cars. They've just fitted a set to the Esprit Sport 350 of Andy Baxter. The Mid Laden Ride Height is a few millimeters above nominal which is where they expected it to be with new springs. It should settle a few millimeters after about 1000 miles.
This is with the Spring Platforms in the 'standard' position. Moving the platforms to the 'lower' position will reduce the Ride Height by about 11mm at the Front and 15mm at the Rear. The car Rides & Handles well.
Update from Lotus Cars
The Esprit Turbo 1980 – 1984 can use the same Dampers as the 85 Cars. The Front Damper is used without the Damper Spring Platform (the spring lower location is on the Suspension arm). The Rear Damper is as used on the '85 car. Damper Part Numbers are as follows:
Poly Bush Components
Lotus have Poly Bushes for All Esprit Models
The Lotus Poly Bush components will replace the standard (rubber) bushes on all models. The only bush that does not have a Poly replacement is the rear Suspension link bush used on cars with Compomotive Wheels.
The Poly Bush replacement components replace the Rubber Bushes as follows (on Pre 1985 Esprits).
Rear Wishbones - A082D4084F replaced with Poly LOTAC05448 (set of 8)
Rear Radius Arm - X046D6000F replaced with Poly LOTAC05457 (set of 2)
Front Upper W/Bone Pivot Bush - X036C6004F replaced with Poly LOTAC 05453 (set of 4)
Front Lower W/Bone Pivot Bush (Rear) - A075C6000F replaced with Poly LOTAC05454 (set of 2)
Front Lower W/Bone Pivot Bush (Front) - A082D4084F replaced with Poly LOTAC 05459 (set of 2)
Contact your local Lotus Dealer or Independent specialist to order the correct parts for your MY Esprit.
Suspension for S1 and S2 Esprits
Currently under development at Lotus
Lotus are currently part way through the S1 & S2 Damper exercise. Pictures of the Development Dampers are shown along with a couple of pictures if the S1 we are using for the exercise.
The S1 (the very first production S1 – 100G) belongs to Gordon Masson who very kindly has allowed Lotus to use his car for this work. Lotus are making good progress on this exercise.
Here's a few reviews from the LEF on the new Lotus Suspension.
Esprit V8 owner
I now have the new springs and shocks all round and the improvement is ENORMOUS. Well worth every penny IMO. The car is just under an inch higher off the ground than it was. Don't forget that springs sag with age, just like facial skin and so the car with the ten year old springs will be lower than a car with new stuff. Hence, the fears about the wrong height are probably reassuringly not founded. Hope this helps ! Also, the factory say that the new shocks are not meant to be adjustable and that they are factory preset for the car for which they are requested. So if you ask for kit for a '98 V8 and then fit them to such a car, the height will be correct....(hopefully !)
Esprit GT3 owner
I've had mine on about 2 months, sadly not enough time to test it but the limited amount of time in the car (done about 100 miles in that time !!!), so far it feels great.
Esprit V8 owner
The V8 I bought had a leaking front shock so I got a new set of the Lotus suspension for the front. Absolutely fantastic so I'm getting the rear done as well even though it doesn't need replacing. No more banging when I go over bumps and still stiff round the corners :-)
Turbo Esprit owner
My point is, I spent £800 ish on the Lotus designed dampers and springs, it's the best fun to £s ratio you can get. You can spend £400 ish on a new chip for the ECU, you can spend £800- £2000 on better brakes but, getting the car to handle right (or even close to it) will add so much to the enjoyment it has to be the best performance enhancing thing you can do.
Esprit V8 owner
I've done acouple of hundred miles in my car now on the new suspension and its the best £800 i've spent on it, really has improved everything about the ride comfort and handling
Esprit V8 owner
hi, ive just had the new suspension and poly bushes fitted to my 99 V8 GT, BIG improvement, i would recommend it. I track my car and have to say, its made a big difference, feels more stable and less wallowing. On the road it has boosted my confidence in the car. The old suspension was original although it had only covered 29k, it was sh......ed.
Esprit V8 owner
I have a 1998 V8 with 62,500 miles on it. I purchased the car new. Recently one of my front shocks completely blew out. Upon further inspection at the dealer, Rothrock Chevrolet/Lotus in Springfield PA USA, it became apparent that both my rear shocks were leaking as well. Furthermore my tires, Dunlop SP9000s, were worn badly. Being that I love this car I decided to completely refurbish the suspension system. Here is what I had replaced.
1. The new Eibach/Bilstein spring/shock combination at all four corners.
2. The new poly bushings for the rear.
3. New standard bushings at the front.
3. A new set of Michelin PS2s at all four corners.
As you can see, this represents virtually a complete new suspension (I consider tires part of the suspension). The cost of all this was the not small sum of $5,000.00. So the question has to be, was it worth it?
In a word, yes. The first thing I noticed was how much quieter the car had become. Now I'm not just talking about tire noise. The new stuff seems to suppress the noise generated as one encounters bumps and the like. Another thing that I immediately noticed was that the new suspension seems to be much more forgiving on initial contact with a bump. Do not take this to mean that it's soft, in fact, I believe that overall it's stiffer, giving the car a more "all of a piece" feel. Turn-in is much sharper. I think that this probably due to both the tires and the new front bushings. The best part by far however is how the car tracks through corners, very little bump steer, it's amazing.
One thing I do not like is that the car sits higher, and this is with the suspension settings set to the lower height. I'm hoping that part of this is due to the newness of the springs and that they will settle with a little time.
Another observation that Espritworld readers might find interesting. My car had developed "wheel wobble". At first I thought the front tires were out of balance. That turned out to not be true. At the same time I had my tires re-balanced I had the wheels checked for run-out. They were out and after straitening the car was much better, but some vibration still persisted. It is now completely gone. I have had the car up to 100 MPH+ and it just sits there, completely stable.
Lotus deserves a lot of credit for devoting the resources needed to engineer this type of comprehensive upgrade for a vehicle no longer in production.
In conclusion, while this is an expensive restoration the advantages are many. First and foremost you eliminate playing "catch-up" with all the suspension components as they go bad one-by-one. Second, since the primary reason all of us own these cars is because of how they perform, the chance to set the cars handling to what is probably better than new is very compelling and I would recommend this to any Esprit owner.
Feel free to e-mail LEW with your opinion on this guide and any other available suspension that could be added to this page. firstname.lastname@example.org
Lotus Esprit World cannot be held responsible for anything you attempt on your Esprit. This is just information which you must decide how to use. Lotus Esprit World doesn't recommend fitting suspension yourself. Please use a fully qualified mechanic.