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        General >> Give/Need advice to/from others >> Toe in?
        
(Message started by: Mike_Floutier on May 29^th, 2008, 5:55pm)

Title: Toe in?
Post by Mike_Floutier on May 29^th, 2008, 5:55pm

This will undoubtedly sound a very silly question but I have to ask it as I was just doing my oil change and noticed that BOTH front tyres (one of which is pretty new) had acquired significant wear on their inside edges.

I see that the "toe in" spec. on the site is shown as "1mm - 3mm +". Now for the silly question. Does this mean that the front of the tyres should be closer together than their backs - that's what I am assuming.

The reason I ask is that the tracking was done a few weeks ago when I changed the track rod ends and one of the track rods.

When I looked at the wheel alignment today it is painfully obvious that I have a significant "toe out" ie. the reverse of my description above - that is, assuming that the back wheels are the same distance apart as the front ones, since they were my point of reference.

Am I on the right track?

Thanks

Mike

Title: Re: Toe in?
Post by cossie_al on May 29^th, 2008, 7:21pm

Hi Mike,
You are correct,
Take a look at this site
http://www.familycar.com/alignment.htm
Hope that helps
Al

Title: Re: Toe in?
Post by Mike_Floutier on May 29^th, 2008, 10:30pm

Thanks Al!

Title: Re: Toe in?
Post by Mike_Floutier on May 30^th, 2008, 10:12am

Ok, well my feeling is; "How hard can it be to do this?"

Just to help me in my thinking and to be open to correction, I'll set out what I plan to do.

1. Check that my front wheels are as far apart as the back ones - ok, done that, they are.

2. Spin the front wheels to check they turn evenly since it will affect the tracking results if they wobble - done that, they are even.

3. Settle the steering into a straight ahead position with no stress on the wheels.

4. Take a long STRAIGHT batten of wood. Place it horizontally on the middle of one front tyre and look along it to see where it points on the back tyre.

5. Measure the distance from said point to the outer edge of the tyre.

6. Calculate alignment. Ok, since the tyre is 60cm diameter and the distance between the fronts of both tyres is 290cm THEN the reference distance for "point 5." above will be the 2mm (+ toe-in) divide by 60 times by 290, ie. 9.5mm (outside the front of the back tyre).

7. Do this for both sides.

Right, well to simplify things I set up the steering so that the off-side front tyre was pointing straight ahead, ie. perfectly aligned with the back tyre (0.00mm toe-in).

I then did the measurements and saw that my bit of wood was pointing 3cm (yes centimetres!) INSIDE the back tyre.

Ok if I divide this by 2 I get a figure of 15mm for each side. Now working backwards, 15mm times by 60 divide by 290 to get the "true" tracking figure I get 3mm (Toe-out) or 3mm - (Toe-in) if you prefer.

Is it any wonder that I've had so much wear on the insides of both tyres in such a short space of time.

I know some people will say that you "have to get it done at a garage" but given care, understanding and a straight bit of wood I don't see why - especially bearing in mind that I DID GET IT DONE AT A GARAGE! After all doesn't this apply to all the work we do on our cars.

This thing about garages having to do the tracking is probably just a myth. We'll see - hehe!

Mike

Title: Re: Toe in?
Post by Tompion on May 30^th, 2008, 10:45am

Mike

I always do my own tracking, but a different method (much as described in Haynes manuals).

I haven’t worked through your figures but a lot of scope for errors in your method, but possible (tyre run out, straightness of wood etc).
It should be measured between the rims & some say by degrees to account for different wheel sizes, but since everything is flapping about on rubber bushes of varying softness/age that seems a bit picky the most important thing is to keep a close eye on your tyre wear once you've set it and tweak the tracking to get it right for your car (talking small adjustments here).

Dave

Title: Re: Toe in?
Post by Mike_Floutier on May 30^th, 2008, 11:34am

Thanks Dave,

Ok, well if you laughed at my last idea then you'll be in fits with this one.

To calculate the adjustment I need to make I looked at the old Granada Haynes manual and it says that "a 19 deg. turn of the track rod will give a 1 deg. turn of the steering wheel.

Well, I found that a 360 deg. turn of the steering wheel gave approximately a 22 deg. turn of the wheels.

So, given that I need to increase my TOTAL toe-in by 10mm (to give 2mm + on each side - from the present 3mm toe-out), and given that 1mm toe = 0.15 deg., I need an angle change of 10mm times by 0.15 which is 1.5 deg.

Now, given what I said about the steering wheel above, I need to adjust the track rod end equivalent to giving a steering wheel turn of 360 deg. divide by 22 times by 1.5 which is a 24 deg. turn. (sounds a lot!!)

So, given the "Haynes figure" above for Steering wheel/ track rod conversion I need to turn the track rod by 19 x 24 deg. which is, surprisingly, only 1.25 turns.

Ok, time to suck it and see.

Will let you know how it goes, obviously I'll check the alignment visually before driving it - lol!

Mike

Title: Re: Toe in?
Post by Mike_Floutier on May 30^th, 2008, 12:25pm

That seems to have done the trick - I've now got a real toe-in around 2.00mm + so I'll just keep and eye on the tyre wear.

Thanks!

Mike

Title: Re: Toe in?
Post by scorpio_man on May 30^th, 2008, 12:41pm

hi mike

you need to watch the tyres aren't 'set' now. the excess wear will continue wear at the same rate as the rest of the tyre, thus looking like the alignment is still out.

hth

Title: Re: Toe in?
Post by Mike_Floutier on May 30^th, 2008, 1:31pm

I'll watch out for that.

THanks

Mike

Title: Re: Toe in?
Post by martin_rowe on May 30^th, 2008, 1:59pm

WOW
dont know why I bought all that equipment for my 'boys' to use when adjusting track.
another way is to drive car around for a bit, then measure the temperature accros the tread, hotter one one at one side means that side of tyre os working harder, adjust tracking accordingly to even out tyre use.
or
a piece of steel rod & a tube that it slides in, place it between front wheels (will have to manufacture some sort of offset)slide the rod out so that one end of the tube is on one wheel, the end of the rod on the other, mark the position of the rod where it comes out of the tube, repeat at other side of wheels, hey presto the measurement is the amount of 'toe'
or
take it & have it aligned correctly.
what a laugh.