Adjusting standard ride height

[ramjet]

So I know I have to put 140kg in the car and half a tank of fuel. I have a 1/4 tank at the moment and got the wife to sit in one side of the car. I did this since according to my measurements I have about 190mm in the rear and about 200mm in the front.

I need to set and tighten the rear as I loosened it off to do the drive shaft seals. The front I have never loosened. If it is sitting at about 200mm now, I would think it was sitting at high before as well.

With the wife sitting in the car (close enough to half the weight required) and the 1/4 tank of fuel, I am not getting near 170mm as the manual says. I presume the arm bolts in the chassis need to be loosened to get the car down to the correct height?

Shocks are all standard. Not adjustable with regard to spring compression.

So I doubt the front ride height has ever been set correctly. My other thought on this is if the alignment has been done and they have loosened things to get the right settings, have they altered the ride heights? I am not sure how to tell them that if they loosen any of this to get things right, that they need to do it with 140kg in the car. Too worried that they would load the seats up with whatever they could find.

This is how it was when bought and the front has not been altered by me. I never questioned it.

[s4simon]

For me. Car with no passengers, 1/4 tank of fuel.

Just forward of the front wheel, bottom of rubber lip to ground 110mm. Just forward of the rear wheel, bottom of side skirt to ground 170mm.

[ramjet]

So I just measured mine in the same places. No passengers, 1/4 tank of fuel.

132mm at the front and 192mm at the rear.

[ramjet]

So what do I do if adding the required weights etc doesn't bring the car down to 170mm front and rear as the manual states?

[sailorbob]

The ride height is not adjustable on the factory set up. The quoted dimensions are the height at where you tighten the bolts to ensure the bushes are in the correct position. Bear in mind the dimensions are for new OE suspension components and worn and / or aftermarket components usually will not meet the specification (even the Lotus Bilstein / Eibach setup sits higher).

[CarBuff]

The replacement Lotus-Bilstein setup offered a few years ago from the Factory WAS somewhat adjustable (3 positions).  It came with a C clip in the middle position.  We were always changing that to the lowest position.

 

Michael, if you see that your car has Spax dampers fitted, that may be the issue.  This brand's stops were too high for the Esprit.  There is likely some discussion on the Forum about what to do, if that turns out to be the case.

[Vanya]

I recently overhauled my suspension, new bushes and coilovers at the front (factory stock) and adjustables at the rear with the perches set up to factory dimensions (same spring rate as factory). My car rides 10 mm higher than factory, this while being weighed down with 2x70 kg + half tank of fuel.

I don't get it either. And no, I doubt my suspension components are bent since the wishbones up front are brand new. 

Granted I have a sports cat, backbox, no EBPV and no spare wheel but that can't really explain the difference IMHO. 

So you're not alone there! 

But where are you taking your measurements to get 200 mm, it does seem a bit much and your car doesn't look so far out of whack in the pictures. 

[sailorbob]

Even when on the lowest spring platforms (the LOTAC05404 front dampers only have two positions) the Bilstein / Eibach sits quite a bit higher than the specification on my car.

[ramjet]

1 hour ago, CarBuff said:

The replacement Lotus-Bilstein setup offered a few years ago from the Factory WAS somewhat adjustable (3 positions).  It came with a C clip in the middle position.  We were always changing that to the lowest position.

 

Michael, if you see that your car has Spax dampers fitted, that may be the issue.  This brand's stops were too high for the Esprit.  There is likely some discussion on the Forum about what to do, if that turns out to be the case.

Car does not have Spax dampers fitted. It is still on the originals. And yes, everything seems fine and none of the dampers are showing any signs of leaking.

48 minutes ago, Vanya said:

I recently overhauled my suspension, new bushes and coilovers at the front (factory stock) and adjustables at the rear with the perches set up to factory dimensions (same spring rate as factory). My car rides 10 mm higher than factory, this while being weighed down with 2x70 kg + half tank of fuel.

I don't get it either. And no, I doubt my suspension components are bent since the wishbones up front are brand new. 

Granted I have a sports cat, backbox, no EBPV and no spare wheel but that can't really explain the difference IMHO. 

So you're not alone there! 

But where are you taking your measurements to get 200 mm, it does seem a bit much and your car doesn't look so far out of whack in the pictures. 

The 200mm measurement was taken underneath the front chassis member as the manual states. The other measurement, underneath the rear hoop.

2 hours ago, sailorbob said:

The ride height is not adjustable on the factory set up. The quoted dimensions are the height at where you tighten the bolts to ensure the bushes are in the correct position. Bear in mind the dimensions are for new OE suspension components and worn and / or aftermarket components usually will not meet the specification (even the Lotus Bilstein / Eibach setup sits higher).

So if I understand you correctly, the car will not sit at 170mm front and rear after tightening everything up and removing the load? This is not a ride height measurement, but a measurement to get when tightening everything up?

Ok. I can handle that. What I am concerned about is that the car will not get to 170mm front and rear even with 140kg and half a tank of fuel in it. If I tighten everything up at an incorrect mid-laden height (I presume that is the 170mm measurement?) what other issues could this cause?

I presume that the rear camber would be out for starters. The tyre shop where I get the alignment done always does a good job and I get a written report as to what was altered, but it is always done with no weight and whatever fuel load I have in it when I get there.

[sailorbob]

4 hours ago, ramjet said:

This is not a ride height measurement, but a measurement to get when tightening everything up?

Essentially, yes.

The suspension geometry should only be checked / adjusted with the vehicle at its 'mid-laden' height. If you mainly drive on your own don't bother ballasting the passenger seat.

[mr.oogieboogie]

I replaced the shocks on mine but kept the springs. Did not use any ballast and had hardly any fuel in it. No spare wheel . Custom Sports cat and custom sports rear box. No issues on height. Space adjustables fitted 

Should have been spax bloody predictive text 

[ramjet]

I wonder why mine is sitting so high then?

I wonder what the tyre shop is going to say when I ask if they can do the alignment only when they have loaded the car up with 140kg?

[CarBuff]

Just a WAG, but has any suspension work been done previously?

 

Tightening the suspension bushes while not at the proper (ballasted) ride height could be affecting the position of the control arms. If this is incorrect it will affect the alignment, AND hold the car up 'on its tip-toes'.

 

Apologies if you've mentioned this already, had a hard day behind the wheel of the Esprit.  (I'm not complaining mind you, I'm just TIRED)

[ramjet]

No suspension work done on the car that I know of or have a record of.

I am thinking I am going to have to loosen everything to get the car 'down' then torque everything back up again. If the 2 x70kg ballasting does not bring the car down to the manual spec, then I am out of solutions. Other than possibly adding more weight?

[Vulcan Grey]

I agree, loosen all suspension bolts that go through a rubber bushing.  Then add weight to ballast, and try and get the suspension to settle.  Then tighten the suspension while loaded.  On alignment racks they have bearing plates to do this, some people add grease between 2 heavy garbage bags under each tire to achieve the same suspension settling.

the hard part is re-tightening the bolts with the car at normal ride height...!  Usually takes a pit.

[ramjet]

Yeehah. I'll be on my back in the garage on the concrete floor.  Sigh.  If I write pit on the floor, is that the same?

If I loosen everything and get the correct height, then measure the wheel centre to the arch height, could I then jack everything up and using another jack or rope, lift the hub to the right measurement and tighten everything up when I can see it?

Theory sounds ok?

[andydclements]

If I understand the idea. then I'd suggest against it.

Do you plan, to tighten the suspension pivot bolts etc, having set the to ride lower than it would naturally with the "normal" amount of weight? ("normal" weight being the 1/2 full tank of gas/petrol, and 70kg per seat)

If I've correctly understood the plan, then, the reason I'd suggest it's a bad idea is: The Lotus process is supposed to result in the bushes etc being un-stresssed in normal use, i.e bushes not twisted relative to their resting position. Having them pre-stressed will cause them to wear out more and also alter (very slightly) the bound/re-bound action.

 

[ramjet]

Andy,

The plan is to loosen everything and set the correct height with the correct ballast. Measure to the arches, remove wheels, reset hub height based on measurement and tighten with the wheel off in each corner so I can get to the bolts.

No intent to set the car at a lower height than that suggested in the manual.

[andydclements]

Ah, in that case, you're doing it the sensible way (for those that don't have a pit/ 4 post ramp etc).

[Vanya]

14 hours ago, ramjet said:

Andy,

The plan is to loosen everything and set the correct height with the correct ballast. Measure to the arches, remove wheels, reset hub height based on measurement and tighten with the wheel off in each corner so I can get to the bolts.

No intent to set the car at a lower height than that suggested in the manual.

It IS actually possible to tighten everything up with the car on the ground, just a bit of a pain. You'll need a helper, but if you really don't wanna chance it or bother measuring distances to arches etc it's the way to go.

I did this on my car. I first tightened things down with the suspension resting on axle stands. I wasn't happy with that, then I loosened things and put the car on the ground, weighed it down and re-tightened. Didn't make much of a difference. I even bounced the car up and down when stuff was loose. 

I think we might be overthinking things when it comes to stressed bushes etc. Technically the car spends 99% of it's life empty on a driveway (which might not even be level) so something will always be under stress... 

[DaKa]

Keen to read the above as I'm getting my ride height adjusted (higher) by Rapid Mechanical Services Ltd, A12 Essex as it is fitted with adjustable suspension. Although I'm not sure if the spare set of springs that came with the car will be needed to make it stiffer - I presume they are for the back?

The tracking/geometry will be done as well so I'll let you know if it concurs with the details above.

I am however a little confused at to where the measurement 170 mm should be checked? Is it just infant of both wheels as stated above, or is there a measurement from the jacking points front and rear?

 

[andydclements]

The 170mm is from the underside of the subframe, tot he floor. When you look at the subframe you realise it's pretty much flat, so the exact "where" doesn't matter too much, unless you go a fir way towards the other end of the car.

[ramjet]

At the back, you measure under the gearbox hoop. At the front, under the front chassis crossmember.

[sailorbob]

The measuring points and the dimensions are not the same for all Esprits.

[ramjet]

You are correct Derek. I forgot that.

I was just wondering why, while eating breakfast, why Lotus didn't keep using the same 2 points and just change the measurements?