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Discussion Starter #1
Can anyone point me to a thread or website with information about the alignment? Most manufacturers deliver cars with only a very rough alignment done, usually to conservative "highway" specs. I assume the alignment Lotus does at the factory will be quality, but the best alignments are done with ballast added to the driver's seat (preferably the driver him/herself).
So, does anyone know what kind of alignment specs the cars have? Will they have been done with a nominal ballast in the driver's seat? What weight would they use? Are all of the specs variable, or are some fixed? Will the LSS and Standard suspension specs be identical or different?

In my limited experience, lightweight cars in particular can benefit incredibly from a performance alignment. My Miata changes noticeably with a passenger because I had my alignment done with just myself in the driver's seat. Changes of a few tenths of a degree can really change the dynamics of the car in a competetive environment. I was able to pick up nearly a full second over a 60 second autocross course (based on my competition's times) simply by getting an autocross alignment done, and I would think the Elise would be affected even more than a Miata.
 

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I wonder if the US Elise alignments are done with a special Federal Approximate Test Anthropomorphic Suspension Standard weight ballast.
 

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All relevant settings are in the service manual.

The Elise needs to be aligned with 75kg (may be 70 with the Toyota powered Elises) of ballast in each seat and 1/2 tank of fuel.

You can adjust:

Caster (front)
Camber (rear & front)
Tracking/alignment (rear & front)

Also more 'esoteric' settings can (and sometimes must, when lowering) be adjusted like the bump-steer characteristics front and rear.

At the front it's done with different mounting plates for the steering rack (very much a compromise.. real fix for the bump steer is a different rack and adjustable arms).

At the back it's done using shims above and below the rear track rod balljoint. Complete 'fix' here is a set of custom wishbones (eg. do a search for 'Pilbeam' and 'Elise') where the track rod is attached to the wishbone itself and not the chassis (which now causes the difference in movement and tracking change when the suspension moves through it's range of motion)

Bump-steer in itself is not such a bad thing (although racers usually like zero), but the issue on the Elise when lowering can be that you move to a different point on the bump-steer graph, so for instance at the rear it now won't always increase toe-in but may have a transient reduction in toe-in (or even toe-out if you run very little toe).

This can cause unpredictable behaviour as you go into a corner and the suspension gets loaded and the tracking makes odd changes.

Bye, Arno.
 

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great anachronism for the US test!! rotfl
 

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Discussion Starter #5
Thanks Arno.

Do you know why they say it needs to be aligned with weight in both seats? Then your alignment is off when you're driving by yourself, which is when I would guess most people would do their performance driving. Pushing it on the track is *not* where I'd like to be worrying about my alignment.

Also, do you know how good the alignment is from the factory? On most cars, it's terrible. The tolerances are so huge that a monkey could get it right. I would guess Lotus would keep the tolerances much lower, but I wonder if it's another one of those cars that just needs to go straight to the alignment shop before any real performance driving.


Ground Loop - :D
Fortunately, I'm not a typical American in that regard. Although, the Lotus has helped me motivate myself to keep the weight down. That and hockey.
 

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Rich said:
Do you know why they say it needs to be aligned with weight in both seats?
'Average use' is probably the best explanation. For mostly track use I'd have it aligned with only your exact weight in the driver's seat (unless you weigh 75Kg that's an approximation too..)

And if you put on adjustable (ride height) suspension then you'd probably want to have it corner-weighted with your weight in the driver's seat only.

But indeed.. The Elise is quite sensitive to things like that. For instance with the default setting and then only the driver in the car on the track you'll notice that the passenger side front wheel tends to lock up first. Simply because there's less weight there..

Also, do you know how good the alignment is from the factory?
Varies wildly.. The camber and caster settings are usually OK, but the tracking can be waaaaay out. Problem is that they do the initial alignment on the bare chassis with the suspension just installed and during the production tings may shift a little.

On my S2 the steering wheel was off by about 30 degrees.. Quite a lot.. It tracked perfectly straight, but the wheel was turned over quite an angle.

But.. Hold off on resetting the alignment after driving a few hundred miles or so. That gives the whole suspension time to 'settle' as the springs settle in their positions and the rubber bushes loosen up a little. Otherwise you'll keep on chasing a moving target.

Bye, Arno.
 

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I understand that each car during stages of build travels through each section on a trolley, and that the car has the alignment/tracking set while it is on this trolley.
I assume then that each trolley can be adjusted to *level* so that the alignment can be accurately set.
I wonder exactly how much weight is placed in the car and where it is placed.(what the exact conditions are that the factory specs are provided for)

BMW M cars are aligned with 150LB in each front seat and another 150LB in the middle of the rear seat. The alignment specs given are for a car in this "state" of presentation.
m
 
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