The Lotus Grand Tourers

Have just had two new tyres fitted at the back this week and decided to get the tracking, alignment, etc checked at the same time. Everything was pretty good except for the camber which was out front and back. Nothing to extreme but ideally something I would like sorted. In the service notes it says that the camber is set at the factory and can't be adjusted. How did they set the camber during production? If I rebuild the suspension what happens then? Was the suspension built with the right amount of camber built in to the angles of the top/lower links or what? I know someone out there must know!

Nothing was adjustable or selected for size as far as I'm aware ... if it was "out" they probably hit a mounting point with a big hammer!

But it's not all bad news ... some Esprits do have camber adjust at the front using an adjustment mechanism at top ball joint. SJ Sportscars sell an upper wishbone kit for the Excel that allows camber adjustment - although this is probably just the kit of Esprit parts (S4 onwards). The Excel and pre-S4 Esprits use the same upper wishbones so the adjustable kit should be a straight swap.

For the rear, some Esprits also have adjsutable top links, they use the same bushes as the Excel so will fit the mountings. However, I don't know off the top of my head if they are the right length within their adjustment range. I had a pair of links made up for my Excel many years ago - I also thought SJ sell them but can't see them listed. I can check the upper links of my Esprit and Excel and get back to you ..

I eventually realised that the reason the camber was out was that my front mount of one of the lower rear wishbones was slightly bent out of shape ... when the toe was corrected using the rear sliding hoop mechanism, it moves camber from one side to the other! I could probably have persuaded it back with either a hydraulic press or a lump hammer!

ps.. Just had another thought, worn bushes or springs could also mean your camber is out so it may be cheaper to change those first if they look suspect. What are your camber readings?

Let me drag this post out of the Graveyard for an additional Question:
Has someone with this adjustable Wishbones Upgrade played around with camber a bit? The Front (or at least my Front) has got a rather hefty negative Camber Angle. Sure great for Cornering, but as Daily Driver I´d like to have a more neutral Camber, so I can get more Mileage out of my Tires. How bad does a neutral Camber affect the Cornering-Abilities of the Excel?

What do your caster angles measure at the front? There's not much on the standard car.

Pete

1.5° ... I´m not sure, but I can´t shake the Feeling, that the Front has been lowered. Springs and Coils look stock, but who knows... maybe someone in the Past torched the Springs a bit. That could explain the Camber. Personally, I like the current Ride Height, so instead of raising the Front I would rather go with the adjustable Wishbones...

Yeah - 1.5 is fine for the track but more than you need on the road with the Excel. The ride height specs are in the service notes - there are two sets of data - one just for geometry assessment and one for actual road use. Have the rears been changed as well do you think? Who sells adjustable front upper arms? I made mine adjustable by welding in some blocks like they did on the last of the Esprits that had adjustable camber. You can increase the caster as well by using shims on the pivot bolt and upper ball joint - again like the Esprit.

Pete

SJ Sportscars made ´em according to Steve C. My first Try would be Lotusbits - I´m pretty sure they either have them or know where to get them... but a DIY-Job would be good as well. The only Thing is, here in Germany it´s a bit more complicated because of the TUEV (our MOT)... you sure know the Term "German Bureucracy"...
The Rear looks stock, so all fine there.

I'm pretty sure the Esprit uppers would fit, although you'd need to check that the length is the same easiest way is check two non-adjustable front arms for part numbers (such as SJ's site). The front suspension of the Model year 85 Esprit onwards (until they introduced adjustable) is pretty much the same as the Excel.

How many tuv testers will have seen an excel.........?
I would do what I wanted.
Bash

I'll try and find my modified ones and put up some photos. You need access to a milling machine and welding gear to make the changes.

Pete

Here are my modified upper arms (ready for a repaint ):







They are made from original Excel arms. One photo shows a stainless plate with a hole - this is how you alter the camber - you can place the hole anywhere along the slot (using different plates) and because the plate is held in place by the recess in the block it cannot move.

Camber can be varied from 0.0 to 1.5 deg negative.

Pete

Nice Solution, Pete
My initial Idea for that was an Intersection with a threaded Rod - like an adjustabe Steering Rod - but a bit more beefy. That would make Adjustments more easy.
@ Bash: Well, the one I work with most Times is an experienced Gearhead... and I work on Vintage Cars for a Living, so I don´t want to trick him. Not just because I don´t want to risk loosing his Trust, but also because he is a Friend. But I´m pretty sure we´ll figure out a Design that meets official Regulations...