tr4a Wonky Wheels

[david c]

At the club meeting last week it was pointed out that my rear wheels do not sit evenly in the wheel arches, I had known this for some time but had not really worried too much about it.........but now I have to investigate.

In my ignorance I had assumed that as my prop shaft did not sit centrally in the tunnel then the wheels would not sit centrally in the wheel arches, but now I think there is rather more to it than that. I put a spirit level against the wheel rims and they are not sitting vertical, I now think that if they were properly vertical the wheels would actually sit right in the arches.

I took the WSM in to the garden and had a good look at section three, and now I am non the wiser, that is complicated stuff, looks like it involves very big hammers and special tools. I have no idea where to start, so before I bowl in and start pulling bits apart I thought I would once again throw myself at the mercy of those much wiser than me.

I will attach some pictures and hope this is something others have had to deal with and that someone can point me in the right direction......please.

 

Ever the optimist David

[Motorsport Mickey]

Bit difficult comparing against your wheel arches David, the bodies separate from the chassis !

 

Although not an independent suspension TR owner I think I should do this first. Establish if the rear wheels both show the same camber, a discrepancy in camber angle ( the tilt of the wheel when viewed from directly behind) will obviously place the top edge of the wheel either further towards the outside (more positive) or further towards the inside ( more negative) camber angle. These need to be adjusted to the WM setting, then measure what the wing protrudes beyond the top edge of the wheel. If different consider what rear wings are fitted to the car, Standard Triumph steel wings are likely more " developed" in their radius ie fuller in their profile. As I understand it a repro steel wing is less "full" ( narrower ) in their width and hence will not stick out as far, measuring these dimensions will give you a basis for future measuring and conclusions to be made.

If all is equal then it's possible the rear of the body could be resituated slightly within it's bolt on bracketry hole clearances to help reduce whatever differences exist.

 

Mick Richards

Edited May 29, 2017 by Motorsport Mickey

[RogerH]

Hi David,

the pic with the spirit level suggests you have a fair bit of negative camber.

The other side looks almost upright.

Ideally they should be the same.

 

Now it gets complicated because as you add load to the car the tops of the rear wheels will move inwards giving MORE negative camber.

 

So if you set the camber to 0 degrees with no proper load then you will stand a chance of getting near to it.

 

To adjust the camber you need to fit the appropriate brackets that hold the TRailing arms in place ~9 http://www.moss-europe.co.uk/shop-by-model/triumph/tr2-4a/steering-suspension/rear-suspension/rear-suspension-tr4a-with-irs-axle.html

 

You also need to know the height of the car because as the camber changes so does the height.

 

Read this before you go too far

http://www.buckeyetriumphs.org/technical/Suspension/AdjRS/AdjRS.htm

 

Is it easy - not really

is it tedious - yes

 

Roger

Edited May 29, 2017 by RogerH

[david c]

Thank you both for your comments.

Both rear wings (in fact all the wings) are clearly repros, the curve at the top of all the wings is quite a poor match for the top curve on the original doors.

I will remeasure from the inner wings to the outside edge of the fitted wings on both sides, this I think will give me a more acurate idea of what is going on.

I had considered "easing" the body over a bit to make things look right but I think I will have to look much more closely at the camber angles.

I have just read the Buckeye section on camber adjustment and will read it again probably several times 'till I understand it, this is proper engineering stuff and takes a bit brain work for me to start to understand it.

I had to weld in new support repair sections for the trailing arms confess during my rebuild I simply replaced the bracketery as I found it...having first replaced the bushes with blue poly.

 

Thankyou again for your help and advise.

[Drewmotty]

Don't concern yourself too much with the relationship between the wheels and bodywork as most TRs are off centre to a degree but it doesn't become evident until wider wheels and tyres are fitted and then line up (or not) with the arches. Concentrate on getting the wheel geometry correct. Paying for a professional four wheel alignment check would be a good start.

[RogerH]

Hi David,

as Andrew states get a four wheel alignment carried out.

The Hunter Hawkeye system works very well. This gives you everything you need to know and lots that you don;t.

 

My local garage does it for free and only charges if it needs (or if he can do it) adjustment.

 

According to Moss you need a one notch inner bracket and a two notch outer - both pointing upwards,

Don't be surprised if you require a ridiculous combination pointing in every which way. Mine are now rather odd but the wheels are happy.

 

Roger

[rcreweread]

David - are you sure all your wire wheels have the same offset? Try swapping the rear wheels over and see if it makes any difference.

 

Cheers

 

Rich

[david c]

Thank you Stuart

I think I will let Hawkeye have a look, and when I have all the info I'll see if they fancy having a stab at it. As I see it if I try and do it myself it's going to mean a lot of trial and error and a lot of jacking up and letting down and even then I doubt I could ever get it spot on.

I have the brackets and notches as specified and the spacers / shims as they were when I took them off, for the cost of a few extra shims I buy a few more and take them along to the garage.

 

I am reasonably sure the wire wheels all all the same, they came off a 5.

 

Thanks again for your help. David

[RogerH]

Hi David,

using the buckeye write-up most of the guess work is removed.

Whoever put the words together did very well.

 

As I mentioned in a previous post I ended up with an odd assortment of brackets and unbelievably it all worked.

 

However it is a great deal of bu99ering about.

 

Roger

[david c]

I think I will stick to plan A and let someone with experience sort this one out, seems that the place that fitted my new tyres (off the car) has a Hawkeye and knows how to use it, apperantly they do some cars for JD Classics hope they don't think I can afford that kind of money!

 

David

[Z320]

Hi David,

I also realised my prop shaft sitting not in the center of the tunnel and worried a little about that for some time.

But don´t care: everythink is OK. It is because the main shaft of the differential is out of the center of it´s housing.

The complete housing is not symmetric, also not the bracket on the prop shaft side.

See the workshop manual, there´s a sketch.

Ciao Marco

[david c]

Thanks Marco

Thats interesting and quite reassuring. I had worried that I had a big problem, fairly sure now that once I have the tracking sorted the car will look "proper".

 

I expect that will be the last problem.....................

 

David