Rear camber -I need to adjust - so how?

Rear camber -I need to adjust - so how?

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magpies

Original Poster:

5,129 posts

181 months

Saturday 9th May 2015
quotequote all
Before taking the care for a four wheel alignment I thought I'd do a check using my cheap magnetic Sealey gauge.

Both fronts are about 0.5 deg neg(I know it is easy adjustment on top ball to top arm bolts which are in a slotted hole) - I would like them about 1.25 deg neg

Drivers rear is approx. 1 deg neg which I believe is fine

Passenger rear is approx. 6 deg neg - yes 6

The chassis did not look damaged when I refurbed it (only needed outriggers)

I cannot see any adjustment - is it done using wedge shaped shims between the trailing arm and the hub?

LawrieS

338 posts

115 months

Saturday 9th May 2015
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Take it you checked at ride height? What are you sticking your level to?

I think wedge shaped shims would be the only way.

Oh, and have you calibrated your level? I got a shock one day when I stuck mine on.

Edited by LawrieS on Saturday 9th May 20:40

magpies

Original Poster:

5,129 posts

181 months

Saturday 9th May 2015
quotequote all
Yes checked with wheels on the ground and stuck gauge on the disc - the wheels I have do allow enough space to put the gauge on the disc and read it (just)

not calibrated but did check against all the door jambs in the house and they were all within 0.5 deg

Edited by magpies on Saturday 9th May 21:03

phillpot

17,105 posts

182 months

Saturday 9th May 2015
quotequote all
Could the four bolt holes where the inner trailing arm pivot block bolts to the trailing arm (where the shims go to adjust toe-in/out) be slotted to give some up/down adjustment ? scratchchin


magpies

Original Poster:

5,129 posts

181 months

Saturday 9th May 2015
quotequote all
thought of that but at that angle it would be too difficult to work out the shape of the shim, but at the hub it would be a straight forward wedge shape - I just needed confirmation that that is the only way

LawrieS

338 posts

115 months

Saturday 9th May 2015
quotequote all
The best place to check would be the mating face of the trailing arm but it's a bit too late for that now.

Not sure how the hub arrangement differs to the drum versions but were all the faces clear of paint and dirt?

I gave the faces of the trailing arms a good wire brush back to bare metal, just an idea that this could've been overlooked if powdercoated, thickness of paint between top and bottom could make a difference.

Same goes for the other surfaces between here and the hub assembly.


LawrieS

338 posts

115 months

Saturday 9th May 2015
quotequote all
phillpot said:
Could the four bolt holes where the inner trailing arm pivot block bolts to the trailing arm (where the shims go to adjust toe-in/out) be slotted to give some up/down adjustment ? scratchchin
Brilliant idea!

ETA, though you'd be fighting against the bush on the outer mounting point.

Edited by LawrieS on Saturday 9th May 21:28

phillpot

17,105 posts

182 months

Saturday 9th May 2015
quotequote all
magpies said:
thought of that but at that angle it would be too difficult to work out................
No angles, I was thinking just lift or lower the inner end of the trailing arm a "touch"?


Thinking about it, how about take the pivot block thing off (bit with the big bush in) turn around 180 degrees and re-fit... see if it makes things better or worse?


This bit.... if it can be fitted both ways?



Edited by phillpot on Saturday 9th May 21:40

magpies

Original Poster:

5,129 posts

181 months

Saturday 9th May 2015
quotequote all
LawrieS said:
The best place to check would be the mating face of the trailing arm but it's a bit too late for that now.

Not sure how the hub arrangement differs to the drum versions but were all the faces clear of paint and dirt?

I gave the faces of the trailing arms a good wire brush back to bare metal, just an idea that this could've been overlooked if powdercoated, thickness of paint between top and bottom could make a difference.

Same goes for the other surfaces between here and the hub assembly.

Never took this apart - they were refurbed by the previous owner and in brilliant condition. but I think shimming where you have circled would be the way.

I'll recheck the camber and talk to a local engineering company about wedge shaped shims. May do a 'temporary fit just placing known shims between the two top bolts, tighten and remeasure until I have approx. 1.25 deg neg

greymrj

3,316 posts

203 months

Sunday 10th May 2015
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Interesting, I must check mine. However cynical we may be about TVR build quality, I very much doubt it was that far out from new. So what has changed? And where is the change? If it was me it would be up on the ramps at a friendly local garage with some straight edges and perhaps borrow one of those small lazer squares. Get to the bottom of the geometry problem before trying to find a solution?

magpies

Original Poster:

5,129 posts

181 months

Sunday 10th May 2015
quotequote all
greymrj said:
Interesting, I must check mine. However cynical we may be about TVR build quality, I very much doubt it was that far out from new. So what has changed? And where is the change? If it was me it would be up on the ramps at a friendly local garage with some straight edges and perhaps borrow one of those small lazer squares. Get to the bottom of the geometry problem before trying to find a solution?
I agree mrj I won't be able to check til Thursday on s a two post ramp. It was a wtf moment just before I finished for the day.

Barkychoc

7,848 posts

203 months

Sunday 10th May 2015
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Are the trailing arm bushes original? Mine looked fine till I removed them - all 4 were totally knackered.

Make sure the basics are right first.
You might also want to consider for the cost of postage asking Adrian Venn to stick your trailing arm in his jig.

Address the cause not the symptom.

magpies

Original Poster:

5,129 posts

181 months

Sunday 10th May 2015
quotequote all
All the bushes are new and the trailing arms were renewed by the previous owner






greymrj

3,316 posts

203 months

Sunday 10th May 2015
quotequote all
That is a really beautiful job. Dont think the trailing arms will stay white for long!!

If there is something wrong now is the time to find it. I am not sure how you are going to check it on a 2 post ramp though as it will be tricky to get it dead level? scratchchinYou are going to have to pick up off the main chassis not the suspension mounting tubes if you are to find the discrepancy.

idea Looks like you have a good solid floor, have you got the tools to get it dead level on stands using the centre structure of the chassis then use one of those lazers to see where the discrepancy lies.
(For a different recent job I actually used a good lazer pen carefully attached to a good spirit level and checked for accuracy over a distance. I used it to find 2mm difference over 4m!)

Good luck, I would be very interested to hear how you get on.

v8s4me

7,234 posts

218 months

Sunday 10th May 2015
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greymrj said:
........ have you got the tools to get it dead level on stands using the centre structure of the chassis then use one of those lazers to see where the discrepancy lies?....
Try one of these....





Get the self leveling one with the vertical and horizontal lines. Not expensive, and will save you a lot of time mucking about with a spirit level and tape etc.

glenrobbo

35,066 posts

149 months

Sunday 10th May 2015
quotequote all
phillpot said:
No angles, I was thinking just lift or lower the inner end of the trailing arm a "touch"?


Thinking about it, how about take the pivot block thing off (bit with the big bush in) turn around 180 degrees and re-fit... see if it makes things better or worse?


This bit.... if it can be fitted both ways?

I have a spare one, but it'll cost you wink



magpies

Original Poster:

5,129 posts

181 months

Thursday 14th May 2015
quotequote all
Update:

dismantled / cleaned off paint etc. and carefully re-assembled. Properly set up the camber gauge and now the reading is 2 deg neg which although more than I want, is acceptable for the Spa run next week.

glenrobbo

35,066 posts

149 months

Thursday 14th May 2015
quotequote all
As a certain Guy would say: "Spot on!" smile