Not that DJ didn't do a great job with his Carlos Fandango laser setup straight from the bridge of USS Enterprise but

I've got a few jobs coming (and one already waiting) up that will require me to do suspension geometry setup

These include:-
Re-align the rear subframe on the black pig
Renew front superstrut on the black pig
Polybush rear end of Hannibal
Custom geometry setup on Hannibal
Adjustable topmounts on Hannibal
Adjustable rear arms on Hannibal
etc etc

With all of these in mind I'm going to need to sell one car to pay for alignments on the other if I have to pay for them

So I'm going to revert back to old school basics with a tape measure and calculator. I think I've designed a jig (during lunch if the boss is looking ) which will allow me to measure toe and camber, thrust angle and possibly even KPI. I should also be able to measure ride height and I have the beginnings of a plan for corner weighting too if I can find a suitable hydraulic setup
A few enhancements might even allow for ackermann (not that I can do squat about it ) and scrub radius

Has anyone mucked about with this sort of stuff in the past? Any comments will be welcome (apart from the obvious skinflint/you tool ones, we all know that anyway!)

Course, if someone wants to donate a 4 wheel alignment rig this will all go out of the window

First pass at a wheel alignment frame. 4 will be required, one per wheel


(image in full res here)

How to use it for toe and thrust angle


(image in full res here)

It should be possible to measure KPI by taking camber measurements at +10deg and -10deg of steering input. This will require the construction of a wheel angle plate. I have an idea for that and using two of said plates will allow Ackermann angle. A bit of indiannudity should also allow scrub radius calculation too

I should add that the adjustable height means that it should be possible to use this on a non level surface (within reason). This means it should work on my drive
Using a 4 wheel "U" tube water spirit level, one per alignment frame, means I can set all of the hubs at the same height.

I'm an even bigger skinflint

For toe, I just stop on a flat piece of ground and sight along the wheel to check front and back line up with the wheel at the opposite end (taking into account any difference in width front to back). Alternatively, a long straight pole.
I normally get it more accurate (less uneven tyre wear) that most tyre places.
I also favour the use of sliding plates you drive over to check wheel alignment as these take into account flex in all the suspension joint with normal loading.

For camber, park the car on a FLAT LEVEL piece of ground and use a vertical spirit level and ruler to measure distance from vertical over the height of the wheel.

For checking position of wheel relative to body (subframe alignment etc.) I would just use a tape measure to a reference point such as centre of bottom swivel.


Not the most accurate, but it depends if you're looking for the last 1/100th second on a laptime or something that's ok on the road without wearing tyres in no time.

_________________
If at first you don't suck seed, try drier grain.

On a video I watched of some Aussies over at Tsukuba for time attack, they used some stands with metal wires on them and then measured off the wheel against the tyre.

_________________
GT Four Adovansu

"I want to enjoy the powerful and nimble agility behavior."

Like this

_________________
René - Carlos Sainz 2433•5000
Turbocelica.nl | ST185 CS restoration and full rebuild

If it ain't broken.. it soon will be

Stringed it up the old fashioned way. If you squint you can just about make out the fishing line I used
(Just for Kris, it was stren 40lb test shock leader )




Offside rear was toed in by 1.5deg, ns rear toed in 0.5 deg

Both sides now toe in 0.3deg
Car now goes in a straight line with the steering wheel centred

Did you lock the steering wheel/front wheels in the straight ahead position to get the string lines aligned or did you just eyeball it?

_________________
Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

Measured it

It doesn't actually make that much difference - there's a screw centred on the hub for setting up the strings. As you turn the front wheels the head of the screw doesn't actualy move in very much for the first few degrees of turn
It's all down to sine waves

The wheel "attachments" - the screw is dead centre and used for setting up the string lines


Ghetto "Slippy Slidey plates" TM, pat pending

Made out of 2 bits of kitchen worktop and well greased. It allows the wheels to adopt a normal position when lowered off the jacks and provides much needed clearence under the car for twiddling the adjusters

Now that's more like it

_________________
If at first you don't suck seed, try drier grain.