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Discussion Starter #1
Hi all,
I am working on re-assembling the front of my Esprit Turbo SE, from 1990. When i took it apart, I laid all parts out very vlearly on the floor, bot left and right side. I also took pics.
I noted that I have one 1,5mm castor shim washer right in front of the rear upper widhbone arm. On the upper balljoint, I have one 1,5mm shim plate on the REAR of the ball joint. Not in front as described in Service Notes and on the Lotus drawing (Section CD, page 2 and 3).

I understand that there must always be a 1,5mm washer in front of the front top wishbone arm, according to text. but the drawing does not show that. It only shows the castor washer before the rear top wishbone arm???

My car have a 1,5mm + 3,0mm setup on the left side of car, and a 1,5mm setup on the right hand side of the car. i also understand that this difference is possible, because of chassis differences etc.

So, should I delete all I had and go for a setup (as a start before geo) as the drawing shows, or something else? and in that case, what?

If I for example move the 1,5+3,0 setup shim plates from the rear of ball joint, to in front of ball joint (as per drawing in book), I see the upright is tilting very much rearwards, so I guess that would introduce extreme castor and strange steering.
What to do?

Any help or explanation that I can actually understand, as I find the Service Notes strange, especially as the drawing and text differs, are MUCH appreciated.

Cheers,
Redfox.
 

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You should set your car up based on the suspension settings recommended by Lotus. The shims go where they need to go to get you those settings. The drawings don't matter other than as a general guide as to where the adjustments can be made.
 
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I would assemble things to get them to look as close as possible by eye or if you can, by measurement. Then get the car on an alignment rack. Putting it back together the way it was assumes it was correct before you took it apart.
David Teitelbaum
 

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Discussion Starter #4 (Edited)
Thanks, but if I suppose so, then some parts would be missing, such as the essential shim washers in between the front upper wishbone arm and the chassis. On both sides of the car. I therefore assume, that my car was not correctly done. I may have to start from zero. My car always felt a bit nervous when going very high speed. It shouldn't. Maybe it never had the correct castor, assuming all other factors are correct ;)
Cheers,
Redfox
 

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It's not possible to get "too much" caster on the SE... The later cars like the V8 have much more caster, and new upper wishbones to allow it. If you have the SE wishbones, then you are limited by that. Lotus added more caster to the later cars due to the power steering, and the earlier cars would have been more difficult to turn the wheel with a lot of caster, and no power steering.
I would add as much caster as you feel comfortable, and that doesn't cause a rubbing issue with the wheel wells. And since you have changed a lot about your suspension, you'll need to get it re-aligned anyways.
I chose some settings more like the V8 (toe-out in the front, camber in the rear) to take advantage of what Lotus changed to later in the Esprit's life. The stock SE settings are too conservative.
 

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The advice above is good. Do you have a camber gauge? If so you can use it to measure your castor. It needs to be done with the suspension at ride height. It's important to have castor angle equal left and right. Too much castor angle can cause heavy steering the faster you drive. I can send you a procedure if you wish.

Regards,
Dan
 

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i run my 90 SE at 2.5 deg castor to improve stability and on-center feel. I think 3 or 4mm spacers it what I used. had to buy longer bolts for the upper ball joint but arms limit it as Travis says. More could could be added with a longer upper arm chassis stud...anyway, you don't want to force the arms in or out as it will quickly wear the arms' bushings. If you find that you can't achieve the desired camber using the procedure in the manual, then the chassis or the arms are tweaked. that might have some effect on the dynamics but might not even be noticeable by an average driver like myself. i could definitely tell the difference between 1 deg and 2.5
 

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Thanks, but if I suppose so, then some parts would be missing, such as the essential shim washers in between the front upper wishbone arm and the chassis. On both sides of the car. I therefore assume, that my car was not correctly done. I may have to start from zero. My car always felt a bit nervous when going very high speed. It shouldn't. Maybe it never had the correct castor, assuming all other factors are correct ;)
Cheers,
Redfox
It doesn't matter what your car was. What matters is what it needs to be now.
 
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Discussion Starter #9
Thanks guys.
So, I am making up a paper template or scheme to fill out for saving the adjsutments I end up with in the cars papers.
Anyway, I have the bare setup now, no washers or shims installed. So, reading the manual, section CD, page 3, it clearly says that at all times, for clearance, there must be a 1,5mm washer inserted between the front upper wishbone arm and the chassis.
My question is this: Does that mean that I should also in the same time, insert a 1,5mm shimplate between the upper ball joint and the rear upper wishbone arm, according to the text's description? Please see picture. The front of car is to the left.
Cheers,
Redfox.

1261178
 

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Discussion Starter #10 (Edited)
Okay, so I re-read the manual and all comments. Therefore the picture an dquestion I posed abve, is nonsense and should be neglected.


So, as a quick guide, is the following correct for the 1990 Esprit Turbo SE front castor adjustment?

1/ both sides of the front of the car must have a minimum of totally 6mm shim washers installed on the stud axle (called inner).

2/ both sides of the car, must have at least 1,5mm washer installed inner on the stud axle, between the front wishbone arm and the chassis.

3/ to find the right castor, one must move over shims between front and rear of stud axle (inner) to obtain the desired castor angle.

4/ Only if one exceeds a total of 6mm washers on a stud axle (inner), one should add corresponding shimplates outer, to the upper ball joint.

5/ shim plates can also be either side of the upper ball joint, corresponding to the added shim washer surpassing the 6mm total amount on the stud axle (inner), being positioned opposite the inserted extra shim washer (across - the opposide side of the upper ball joint, called outer).

6/ stud axle should be 282mm long, and nyloc nuts should NOT be the long type. Otherwise, the axle may not be long enough, and there's not enough room for longer ones.

7/ the two front bolts for the upper ball joint can be a longer type if need be, to accomodate for thicker washers, if used.

Cheers,
Redfox.
 

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its pretty simple. the idea is to move the top ball joint rearward while keeping the upper arms square. so the upper ball joint should normally always be touching the upper rear arm with no shims. other than that, you want to use as few shims as possible (though retaining that 1.5mm shim). I fit the shims on the stud and snug the nuts on the stud (with fresh bushings in the arms) and then with the ball joint against the rear upper arm, measure the gap between the ball joint and the front arm. fill it with shims. if everything undamaged, the thicknesses of the shims (not counting the 1.5) on the stud should be the same as that gap. if not, its not the end of the world, but hopefully not too far off ideal. the stud will limit how many shims can be fitted on it since at least one thread should be exposed on front and back in order for the lock nuts to be safely engaged. be aware that JAE and possibly others have studs labeled the correct part number but they are 272mm and too short to use
 

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Discussion Starter #12 (Edited)
Exactly, and I just bought two of those, so discarded them and reused the original ones at 282mm.So, with the rear stud axle installed with 6mm in total and the nuts nipped, it looks like this with thetwo front bolts inserted, not tight:

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If I take off these two front bolts, the upper arms split even more, like 1,5cm.
Next picture below shows it all tight, 6mm total inner, and zero shimplates in the front on the top ball joint.
So, I read the manual like with 6mm inner, no shimplates should be inserted, as I do not exceed 6mm on the rear stud pivot bolt.

I jsut think it's alot of space, or when tightened, pretty tight. I don't know really...

The last answer you gave, following that, should I anyway insert some shimplates to ease the load on bushings? as I think what I have now, may load the upper wishbone arms up a bit. Or I could tighten it all up, and then loosen it again and then measure if the upper arms came closer in loose condition.

1261276



Cheers,
Redfox
 

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do the arms have new bushings installed? the arms don't seem to be square if the gap closes when you install front bolts. I have not experienced that issue. to answer your question, yes filling the gap with shims is how I do it and it seems to work for me.
 

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Discussion Starter #14
The arms does not seem bent or not straight. No damage to chassis. No bent stuff. Yes, I installed new original Lotac red polybushings.
Car rode very well before, albeit a bit nervous at high speed. The castor were all out of spec it seems.
So, I think I will play around with shimplates and try to find themost relaxed position for the whishbones.
Strange...
But thanks fo rall your input. I now know how the system works and it is indeed quite simple. I am building a setup for measure it al lup and do all tweaking by myself.

Cheers,
Redfox.
 

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do you get the same thing on the other side of the car? i have done it 3 times and not experienced what you describe
 

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Discussion Starter #16
Sorry, but I cannot say yet, as I have been awaiting another front arb bushing to press into the lower arm an dreassemble. But, that of course that is independant of the upper wishbone arms, so I shall work on it asap tomorrow and get back with an answer.
Cheers,
Redfox.
 

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Discussion Starter #17
I've now measured the other side in a similar setup, and the airgap between the two upper wishbones are similar to the left side of the car. They are parallel it seems.
So, not to stress the bushings, I inserted two 3mm shimplates in front of the uper ball joint. That may give a lot of castor, so to be able to tune it in as normally, shouldn't I moce one of the airgap shimplates to the other side of the upper ball joint, so that it is equal. Otherwise, I'll throw the number I gain with the shims at the rear off.
Cheers,
Redfox.
 

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i have 6mm shim on one side of the ball joint to achieve about 2.5 deg which is a good number for me. it is not as much as the later cars with power steering. i would leave them on same side. Please post your alignment printout when you get it to the shop and your driving impression
 

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I would start out with the alignment specs recommended for your year. If that doesn't feel the way you want then discuss it with the shop and see what they think. Each spec is a compromise and when you deviate from a spec you introduce other, unwanted effects. At least start from a known spec and make sure the car drives straight, returns well, and isn't chewing up the tires. If you can't get the car to the OEM specs you must find out why. Something is worn or bent and you should not try to adjust it out. That is not why they built in a way to adjust things. While you are concentrating on the front, don't forget the rear wheels have to be checked and adjusted if necessary too. Make sure the tires are not too old and you have the correct pressures. Before you start, the ride height must be checked. When you go to the shop you should have all of the loose stuff out of the car, 1/2 tank of gas, and if the shop is really good they will put enough weight in the driver's seat to simulate you in the car. Bring the alignment specs with you. It should be in the machine but if it isn't they can enter it manually. If possible you should bring a kit of shims. A good shop can make them but they will charge you for the time. Sometimes the shop can get by just moving the shims around or taking them out but often they will need some. Bring the torque specs too. Once the alignment is set it really can't change unless something becomes worn or bent (or you take things apart).
David Teitelbaum
 
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