Front Suspension alinement

[Richmmm]

Hello Everyone

I have recently rebuilt the front suspension, because of MOT advisories for the ball joint covers. As usual, I had a few issues with stuck bolts and i needed a new trackrod end.

When i dismantled everything, I noted the position and number of alignment plates on the top ball joint - 6 on the rear side of the joint. I am guessing that is probably not the optimum number and position of the plates......I reassembled the suspension in the same way as I found it.

So next issue is to get the tracking done due to the new trackrod end. I find that the lock nuts are seized so will need to be cut off and replaced, and then to the garage and adjust the tracking.

Is the tracking affected by the suspension alignment or vise-versa? Should I get the suspension set up first, then do the tracking?

Regards, Rich in Walsall

[Tuga2112]

reinstalling stuff with the same setup you had when removed is not guaranteed to maintain geometry, not to mention you dont know if the geometry was correct before taking it apart.

i cant speak from actual knowledge. my reasoning leads me to expect changing the geometry may affect the tracking (because the steering pivot point may have changed). while changing the tracking will not affect the geometry (the end of the lever point will not affect the wheel's camber or caster direction).

last time i gone to the "standard" places to get my geometry done. they refused to touch a car with shims (specially after i said theres camber shims as well as caster shims). and told me to go to either the ferrari garage 30 miles away or a very specific racing specialist 50 miles away and either would have been more than £500 for the job, with the cheaper option being a 2 visit task because they "make their own shims after measuring the required offsets.

i ended up driving 80 miles south to a lotus 'specialist' that had pictures of restoring a M100 on their website.... to be utterly disappointed with the fact he didnt have shims in stock (despite 2 weeks notice email warning shims would be needed) and was trying to force geometry to be right by positioning shims in the wrong orientation (they can be directed 3 or 9 o'clock.. he fitted them at 12...) so. after what was more than £300 out of pocket i decided to DIY with the help of a local friend that had a m100 back then and has restored multiple europas over the years.

my advise is to get your wallet very much ready, because unless you find a local friendly independent who genuinely wants to do it for the sake of bragging about it, i would expect it to be expensive business

[dapinky]

Whilst every adjustment has "some" effect to other things, there is an accepted wisdom that says the order for adjustments is as follows:-

Front tracking
Rear tracking
Front Camber
Front Caster
Rear Camber
Front tracking (again)

The reason being that (assuming the chassis is straight, flat, and not distorted) the front tracking is the closest to an 'in-line' adjustment, as although the track rod end is not exactly central to the height of the wheel, it is very close, so will have the least effect on the rest of the adjustments).....also, this is the measurement which is most likely to be "wrong" in ost cases.... it is also the one that can be changed with a simple mechanical adjustment, requiring no new parts (unless it's all seized solid!).

Then the rear is the next likely to be already close/right - and is again a mechanical adjustment of cam-bolt and thread length changes.

Camber is a very quick measurement to take, but the most difficult to adjust - hence leaving it alone whilst the rest is checked...... this has the biggest effect on the Caster measurement, so the 2 are often done at the same time, as the measuring is interlinked by measuring the camber during the wheel-turning through a certain set of angles.

Changing the caster is a case of moving shims front to rear (or the other way) and relies on the bolts through the top wishbone being free to move - worth checking before you go and spend money as if they are seized, you will need a new top ball-joint..... and the same bolts need to be removed to change the Camber shims (unless it's an early car with cam-bolts).

It is the final Camber which is the easiest to measure, but trickiest to get right (but once right *should* never need too much attention)...... it requires the 'correct' shim to be used in matching pairs (front/rear left & front/rear right). There is a mathematical correlation between the shim relative length and the angle of change, so measuring what you have fitted, means the garage should be able to work out what you actually need... but it obviously needs to come apart to see what you already have..... so the garage may or may not have the correct shims in stock (as Joao says, they may try to adjust what is available).

I have always just made my own shims from 4mm stainless steel by drilling an 8mm hole in a small sheet, then trimming it down with an angle grinder to get the right clearance to the edge, then trimming the other 3 sides to the correct dimension to fit in the wishbone....... you can get it exactly right and not jus within the right range.

Final check of the tracking is to see if it has moved at all, and to centralise the steering wheel.

[Tuga2112]

Front tracking
Rear tracking
Front Camber
Front Caster
Rear Camber
Front tracking (again)

im going to have a very busy day sometime soon.

[Richmmm]

Yes Thanks for the info.
My top ball joints are new so access to the shims is easy at the moment. The plates are all in the same positions, the notches all pointing the same way, I think they were in the wrong position when I dismantled them.

I will get the tracking sorted first then, once I have freed up the locking nuts on the trackrod ends. I will see how much my local garage can do about measuring the angles, failing that it may be a trip to a proper lotus garage. My wallet is quivering already!

Ta, Rich

[Fredjohn]

In theory you don't need to use a Lotus specialist. Just search for Hunter Hawkeye alignment in your area. The machine has a large database of suspension settings for cars, including the M100 Elan.
The slight downside is they probably won't have spare shims to hand. But the ones you have on your car may be suitable if correctly positioned or turned over. Or you can buy from a Lotus dealer once you know sizes or make your own.
The machine can also do rear alignment.

[dapinky]

In theory you don't need to use a Lotus specialist. Just search for Hunter Hawkeye alignment in your area. The machine has a large database of suspension settings for cars, including the M100 Elan.
The slight downside is they probably won't have spare shims to hand. But the ones you have on your car may be suitable if correctly positioned or turned over. Or you can buy from a Lotus dealer once you know sizes or make your own.
The machine can also do rear alignment.

This is true - you get them to adjust whatever they can get at, and do with spanners...... then with the print-out they give you, you work out how far in/out the top of the hub needs to move and obtain the correct shims accordingly (if required!).....

...... I've never used the specialists, so can't say how long I would expect it to take them with all the Gucci kit - but it takes me a few hours using bits of wood, string and accurate measurements in my garage!!!!

[Simon_P]

You can get the tracking close enough with a roll. of string and a tape measure .
The camber can be done with a piece of aluminium angle, 2 bolts and four nuts and a bubble level app on your phone.

See YouTube for how.

[dapinky]

You can get the tracking close enough with a roll. of string and a tape measure .
The camber can be done with a piece of aluminium angle, 2 bolts and four nuts and a bubble level app on your phone.

See YouTube for how.

Whilst I do all my own alignments in this way, it is imperative that you also have an absolutely flat. level surface to work on...... a driveway with paver blocks isn't good enough..... fine in a concrete-floored garage (with enough room to work).

What hasn't been mentioned yet, is that before you start, you set all tyre pressures the same (26-27 psi in most cases), and if you have adjustable height shock absorbers, that the ride height is adjusted to the correct dimensions......

.... I have a collection of bits of wood the right lengths to put under the car for ride height setting, then run a length of string along each side of the car at mid-wheel height, held up with axle stands. When the strigs are completely parallel, it is "just" a case of measuring between the front and rear edges of the wheels and the string, and working out the 'toe-in' or 'toe-out' (remembering that you may need to use a bit of trigonometry to change from mm to degrees and vice versa - depending on the actual wheel size, the mm will change, whilst the degrees don't).

A bubble gauge is probably enough with modern phones being very accurate, although I do have a proper Camber gauge and it makes the measurements simple)......... if I want to do the Caster measurements, I simply park with the 2 front wheels on a 'sandwich' of 2 pieces of hardboard, with the shiny sides together, so that when you move the front wheels through the 60 degrees required to take the measurements, the tyres don't drag on the ground - by far he hardest part of the whole thing (once you've ensured that the bolts will adjust!) is setting up the parallel lengths of string accurately (and remember to thread an m12 nut (or similar) on the string to make sure it doesn't blow around with ambient breeze, and remains taught.

[Tuga2112]

if we are getting pedantic here. you also need balast in the driver's seat to a similar weight to the driver...

[simonbuk]

if we are getting pedantic here. you also need balast in the driver's seat to a similar weight to the driver...

And half a tank of fuel !

[simonbuk]

As regards to going somewhere with Hunter alignment equipment - just been and done that - they didn't want to touch any caster or camber plates/shims ? So basically giving you a print out of the current settings and only able to adjust toe in/out settings and rear camber settings ?

So we probably need to go to a Motorsport set up service who are willing to spend the time on it - and maybe do corner weights and height adjustments too ?

[Tuga2112]

Simon,

i had this whole shebang problem 4 years ago after doing my car up.

what i found was that nobody wants to touch shims unless theres a lot of money involved. they do not have the willingness to risk having to re-do the job multiple times until its right. not to mention they must be aware of how long it takes. and with any old car like ours. the chances of a seized nut are far higher. not to mention some things are just weeks away from replacement. leaving a lift stuck not being profitable.

so, i had it done by the only person i found that was willing to do it.. and i was not happy with the way it was done.

i will be doing it again, myself. but getting the end results checked by the garage. and i would advice taking the same approach unless your money is burning a hole in the wallet

[simonbuk]

Well I took mine into a place with the Hunter alignment tool, front toe in was slightly out so got brought back into tolerance which made the camber also OK. My castor was at zero so took it home and moved a couple of shims , this should make it negative 1 degree. Back to the alignment shop tomorrow to see what effect it has happened. Doing a front alignment check is only 20/25 quid so don't mind getting it rechecked for that, think you just get the measurements for that , not another colourful print out !