Do you have a link to your photos Dave, I would be really interested to have a look and get some ideas.
Regarding the -ve camber, my tracking is set up with 1/16" toe in, so there's no issue there it's just a factor of lowering the car, I think I'll have to do the stub axle mod next but I having been out for a drive on slippy roads around my favorite roundabouts this morning, I can confirm that however many excessive degrees I'm running results in a rather nicely balanced car, not sure it's so good for tyre wear though.
Setting-up the suspension
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Hal Mercier
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Re: Setting-up the suspension
So it's either your running very short springs or the front shock towers are fitted too high on the shell...
Re: Setting-up the suspension
The springs were supplied by Tim D for the car (I asked him for a fast road/track day set up), it is low but it does sit nicely front to rear, if I correct the front camber the front end will come up a bit, and increase the contact patch and so 2 issues sorted with one mod (hopefully) and then go from there.
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Hal Mercier
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Re: Setting-up the suspension
All I can think is your shock carriers are mounted too high on the shell. Mine were 13mm different measured off the floor.
Re: Setting-up the suspension
Sorry Hal, when you say that you mean that one side was 13mm higher than the other?
I'll ask the stupid question, I don't suppose there are any dimensions for where the shock mountings should be fitted on a Mk5?
I'll ask the stupid question, I don't suppose there are any dimensions for where the shock mountings should be fitted on a Mk5?
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Hal Mercier
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Re: Setting-up the suspension
No question about this sort of thing is stupid....it's stupid to not ask!
Yes, I meant mine had been set up wrongly by whoever built the kit in 1970. Tim told me recently that Adrian & Co Ltd sent the early shells out without fitting or pre-drilling the suspension mounts, and that (as there were no proper instructions) most cars were wrongly set up by the buyers. My left mount was 13mm higher than the right one.
I think what I can do is measure the distance from, say, the rear seam on the front wishbone, with the wishbone horizontal, to the top of the shock mount where it meets the bodyshell. I can do it on the Mk 4 easily right now as it's on axle stands and has the wheels off, and a flip front.
You will obviously need to jack your car up so it's the same height side to side, and both front wishbones are horizontal.
OK the measurements I just got are...with wishbones horizontal, just under 37cm.
With wishbones at full droop with the shocks on, my measurement is 38.5cm to the bottom of the rear seam.
I have AVO units supplied by Tim. You do, I suppose, have them mounted correctly, with a large rubber buffer enclosed by two cup washers between the top of the shock and the inside of the shock tower? There should be a shallower rubber buffer and washers above the top of the tower under the shock nut.
Easy to see here, distance is from bottom of rear seam to top of tower where it touches the shell.
One other thing, what weight springs have you got on the front? I'm not sure what mine are, but they look like a set of spares which are 200lb The red rear springs are 300 lb. Why would I have got two sets of 200 lb springs? Maybe the ones on the car are less, but the script is only visible with the springs off the shocks as it's written on the flat end of the spring.
Yes, I meant mine had been set up wrongly by whoever built the kit in 1970. Tim told me recently that Adrian & Co Ltd sent the early shells out without fitting or pre-drilling the suspension mounts, and that (as there were no proper instructions) most cars were wrongly set up by the buyers. My left mount was 13mm higher than the right one.
I think what I can do is measure the distance from, say, the rear seam on the front wishbone, with the wishbone horizontal, to the top of the shock mount where it meets the bodyshell. I can do it on the Mk 4 easily right now as it's on axle stands and has the wheels off, and a flip front.
You will obviously need to jack your car up so it's the same height side to side, and both front wishbones are horizontal.
OK the measurements I just got are...with wishbones horizontal, just under 37cm.
With wishbones at full droop with the shocks on, my measurement is 38.5cm to the bottom of the rear seam.
I have AVO units supplied by Tim. You do, I suppose, have them mounted correctly, with a large rubber buffer enclosed by two cup washers between the top of the shock and the inside of the shock tower? There should be a shallower rubber buffer and washers above the top of the tower under the shock nut.
Easy to see here, distance is from bottom of rear seam to top of tower where it touches the shell.
One other thing, what weight springs have you got on the front? I'm not sure what mine are, but they look like a set of spares which are 200lb The red rear springs are 300 lb. Why would I have got two sets of 200 lb springs? Maybe the ones on the car are less, but the script is only visible with the springs off the shocks as it's written on the flat end of the spring.
Re: Setting-up the suspension
Thanks very much Hal, I'll check the heights on the weekend, it may not be significant due to build differences but, the clearance between the top of the shock mount and the GRP return over the mounting looks to be quite a bit more than on mine.
I have fitted the shock mount rubbers correctly, but am not sure what the spring rates are, I fitted what Tim supplied and didn't ask, mine also has AVO shock absorbers.
I was going to say I was surprised that some of the shells were not pre-drilled but then again perhaps not, if only I had known prior to rebuilding the running gear I would have been a bit more questioning and technical in my approach rather than just bolt the parts back on.
I always knew the car would take some development but I did think that the basics would have been correct, the snag is that the suspension that was on it was not the original set up either so (I think) sat rather high, as in the photos posted on here just after I bought the car, so apart from the measurements you have just given me I have little to work from.
I have fitted the shock mount rubbers correctly, but am not sure what the spring rates are, I fitted what Tim supplied and didn't ask, mine also has AVO shock absorbers.
I was going to say I was surprised that some of the shells were not pre-drilled but then again perhaps not, if only I had known prior to rebuilding the running gear I would have been a bit more questioning and technical in my approach rather than just bolt the parts back on.
I always knew the car would take some development but I did think that the basics would have been correct, the snag is that the suspension that was on it was not the original set up either so (I think) sat rather high, as in the photos posted on here just after I bought the car, so apart from the measurements you have just given me I have little to work from.
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Hal Mercier
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Re: Setting-up the suspension
It's a bit of a problem isn't it!
I suppose if someone was setting a car up for rallying, you'd raise it at the front simply by using longer stroke shocks and long springs. The towers could also be lowered on the shell if necessary, then to compensate for the resulting positive camber, the central pivot points would need lowering too.
The rear end is simple in comparison.
I only found out from Tim last week about the shells not being pre-drilled, and I did the same as you when we built the car for racing in 2001, otherwise I'd never have taken it out with the settings so wildly out.
I really should stick it on a proper jig to be 100% sure it's right now but I don't have anything suitable here at the moment.
Your car looks plenty high enough in the avatar, why is that? Were the coilovers you removed much longer than the AVOs?
I'm also wondering if our AVO units are in fact the same...what's the eye to eye unloaded length on yours?
Mine are 32.5cm from top of the shock mount to the centre of the lower bolt eye.
I should think what's happened in your case is that the car was built using excessively long front coilovers, and to compensate for the extra length, the mounting brackets were fixed at the maximum possible height on the shell.
Then when you fitted shorter units the front was much lower, so the central pivots were lower in relation to the hubs, and the negative camber was the unavoidable result.
To rectify, lower the shock mounts using my floor to tower top measurements.
I'm not saying it's definitive but my camber seems to be about right!
I suppose if someone was setting a car up for rallying, you'd raise it at the front simply by using longer stroke shocks and long springs. The towers could also be lowered on the shell if necessary, then to compensate for the resulting positive camber, the central pivot points would need lowering too.
The rear end is simple in comparison.
I only found out from Tim last week about the shells not being pre-drilled, and I did the same as you when we built the car for racing in 2001, otherwise I'd never have taken it out with the settings so wildly out.
I really should stick it on a proper jig to be 100% sure it's right now but I don't have anything suitable here at the moment.
Your car looks plenty high enough in the avatar, why is that? Were the coilovers you removed much longer than the AVOs?
I'm also wondering if our AVO units are in fact the same...what's the eye to eye unloaded length on yours?
Mine are 32.5cm from top of the shock mount to the centre of the lower bolt eye.
I should think what's happened in your case is that the car was built using excessively long front coilovers, and to compensate for the extra length, the mounting brackets were fixed at the maximum possible height on the shell.
Then when you fitted shorter units the front was much lower, so the central pivots were lower in relation to the hubs, and the negative camber was the unavoidable result.
To rectify, lower the shock mounts using my floor to tower top measurements.
I'm not saying it's definitive but my camber seems to be about right!
Re: Setting-up the suspension
The picture in my avatar is of the car as I bought it, but I'm pretty sure the set up was not as built, I'll post a side view up of how it sits now this evening for comparison and comment.
Re: Setting-up the suspension
As promised some photos of the car as is now, I wish that I had taken a side photo that was more perpendicular now, because although I hadn't noticed it actually looking at the car, now that I have just looked at the photos it does look lower on the front
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