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But are you saying that there are suspension settings that can make the car sit higher/lower ?

you need suspension which has ride height adjusters.

I've got a full set of Gaz shocks and springs for an early stevens, with ride height and damping adjustment. PM me if you're interested.

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Hans, your car looks fine.

Colin, your looks a bit high.

I've been speaking with Lotus about my ride height a lot over the past few weeks, about how critical it is, problems and so on.

I like the idea of adding arches that WILL mask the wheel arch slightly but dropping the car ~10mm all around will probably be fine and look perfectly acceptable.

What you have to keep in mind is that you NEED body roll to allow the car to weight shift in turns and under breaking / acceleration. On a track car stiffening and lowering the suspension is fine as the track is usually cambered and nice and smooth, plus the car has much more grip with the surface and usually track orientated tyres - on normal roads if you start taking it to the extreme you will skip all over the place and lose grip and so on - suspension, or a correctly setup suspension is everything !

Colin, if I was you I would seriously have the car's geometry checked out and the ride height assessed properly - doesn't look right at all.

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What you mean ? about the suspension issue or the use of missing words ? :lol:

Each to their own but if you want a low rider Esprit dont expect it to behave like an Esprit - if you drop the car 30-40mm and hit a deviance in the road at speed expect the car to do all sorts of wierd things. If you turn a sweeping corner expect the suspension to bottom out and the steering to go wibbly wobbly. Change its ratio front to back is asking for even more trouble.

If you drop the car, fit stiffened springs and or adjustable dampers, or you risk all sorts of nasty stuff happening - bump steer being one of them where the suspension absorbs something like a dip in the road and the front goes into toe out and drags the steering to one side sending you into the armco at 70mph.....

Nee offence but I think the advice of cutting the standard springs is just plain dangerous ! :animier:

FWIW the standard car has a ride height tollerance of +/- 5mm

Jon.. while I respect your opinion.. I trust you are speaking from experience.

I have done over a few Esprit (with professional race car fabricators I might add).. I have reverse engineered the Esprit suspension data into a 3D suspension analysis software program to find the limits... (and the bump steer issues you imagine)... I have even run the cars in the conditions you worry about (with no drama).. your argument is simply that..

By the way, your car appears to sit a lot lower than the Can/US S3 and Stevens cars.. in which case 30-40 is too much. Lowering the car does required more spring and damper control hence the ride is not soft and cushy anymore. But lets face it the Lotus IS suppose to be an exotic?!

i dropped my old 88 turbo with the protech springs and dampers( its currently on ebay at the moment) it drove like a pig ,my advice is to stick with the origional spec

If the springs and dampers are too stiff you will have a very uncomfortable car to drive.. The springs on these cars dont need to be uprated very much at all and damping needs to be only enough to control the wheel. Heavy springs and tight dampers will have ruined the cars comfort and road handling for sure.

Edited by f1karting

If you set no goals you shall surely reach them..

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I spoke to Brian Angus about this with regards to the S1 suspension program and fitting alternative springs and dampers.

First of all I would ask your self why people buy a Lotus

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Not wishing to speak for Lotus but they do have to make their cars for the public and for use on roads hence the suspension setup (as described by Rojer Becker on that Evora video) - not everyone wants the car to act like it does from the factory but for the majority of customers it works.

I think Travis once said quite rightly that the only person who knows how good their car is the driver, so I wouldn't advise against adjustments esp if you know what you're doing and especially if it's good for you, some people prefer a more promoted oversteer, harder ride, more response and so on - others just want plain comfort. The setting from the factory is a compromise for all worlds.

Lowering the car (apart from cosmetics) obviously lowers the centre of gravity closer to the ground which makes the car more responsive/alert to the steering, however to stop it bottoming out on the ground and the dampers you have to stiffen the springs or increase the damping rate which then vastly reduces the weight shift ability (something you need to move the weight of the car over the tyres in contact with the road to produce grip - ie front for braking, rear for accelerating for rwd and side to side for corners) - remove that and you have to fit huge hoofing slick tyres to maintain grip - something we cant do on a road car.

The reason why I commented was that IMO I thought that advice was dangerous. If you chop springs down on a car there are a world of problems, not just with the spring mounting itself on the damper platform - the spring has to be finished off so under load the weaight of the car is projected right down the centre/middle of the spring - chop that bit off and the spring will tend to want to bend under compression or worse still fly off the platform under de-compression !

Not to mention the huge dynamic effect it will have on the car's ride/handling characteristics by dropping it that much. Cutting springs is a real cowboy way of lowing any car, net alone a car like this !

Lop 40mm off and the complete geometry setup...you might as well throw that out of the window and start from a fresh.

You'd have to re-set the car up from scratch for a start, my immediate concern is the camber - even on a perfectly level road you will eat tyres as they will carry all the wear on the inside. You have bump steer as mentioned, suspension bottoming out, weight shift issies side to side, front to back - I could go on all day !

All this soft and cushy vs stiffly sprung lark does make me chuckle a bit - what happens to a highly sprung car when it hits a bump in the road ? The car flys over the bump and lifts off, losing traction...hard suspension does not allow for changing road surfaces at all well, bumps and weight transfer - fine for a nice smooth banked racing circuit with no bumps in but not so good for the road.

Good example is to see F1 car data from a circuit like Hockenheim vs Monaco (fast circuit vs road circuit) and look at the huge difference (in F1 terms) of the car's setup.

Suspension is everything and works in harmony with the whole car's design from tha chassis upwards - if you screw around with it too much the whole lot is kaput.

Yep it's fine to say people tuned the racing Esprits to this level but they have as much resemblement to the road cars on the inside as chalk does to cheese. Messing with it by the amounts mentioned are only needed if you're looking to race the thing around a track. I'd rather have a comfortable safe car than one that shakes your bones to dust and twitches at every opportunity - but that's just my opinion !

End of the day do what you like to the car but if I knew I was getting into a car with the springs cut down like that, I'd probably get back out again, for good reason.

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I dont know why you feel you have to talk in extremes and worst case scenarios all the time.. that is not what we are talking about here. I have developed some very sensible and well behaved cars.

To your credit, you do make some valid points.. ..of which all need to be considered and accounted for in any chassis tuning program.

However, by your tone, you seem to think I obviously have no idea what I am doing!

You are entitled to call me down. However, the one thing I do have is the knowledge gained by experience. (that I am willing to share that with anyone that is interested)

..it seems you aren't, so well leave it at that.

If you set no goals you shall surely reach them..

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I seem to recall Keen from the turbo list did something with a rubber spacer on the perches and lowered the car. I think it was reversable unlike cutting the oem springs. Normally when one lowers a car stiffer springs are called for, maybe shocks with a different bound and rebound settings to make it work right.

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Without getting too technical, when a car is lowered the angle of the control arms changes, drastically if the lowering is excessive. That can have a negative, even severe, affect on roll centres and camber change. Those control arm angles are often and in the case of Lotus most likely optimised.

As for bump steer, 3D imaging is fine but to be absolutely sure remove the springs, re-assemble the suspension and work the wheel through its travel. Make a pointer and see what bump steer, if any, there is.

And for cutting springs, it can be done but to be safe no more than half a coil from each end and have them re-tanged and/or ground to restore their squareness. There is a formula and technique to calculate the old and new spring rates as well.

Edited by DanR

DanR

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I should get a commission, but if you attempt any sort of modification to the suspension of a Lotus without the sort of basic knowledge contained in this book then you deserve no sympathy when out a couple of grand and a worse handling car.

http://www.amazon.com/How-Make-Your-Car-Handle/dp/0912656468

Life is like a sewer, what you get out of it, depends on what you put into it. (Tom Leahrer)

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Without getting too technical, when a car is lowered the angle of the control arms changes, drastically if the lowering is excessive. That can have a negative, even severe, affect on roll centres and camber change. Those control arm angles are often and in the case of Lotus most likely optimised.

Therein lies the problem, you're driving the car on a level which is was never ever designed to be. The tollerance for the ride height was +/-5mm from the norm.

This is to incorperate the bound and rebound of the whole suspension system (trailing arms, control arms, wishbones and so on) during normal road use.

Once you start lowering the car (or raisining it for that matter) by extreme measures, when the suspension moves it is in a place where it was neer designed to be in and the bits and bobs that hold it together do not function as they were designed, form follows function.

Lotus themselves actually said the lowest they could safely drop the car was by 10mm for the new suspension they released.

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