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Strut brace installation

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I'm posting this for three reasons:

1/ I want to know how you guys got on and whether you think it made a difference. Took me 15 min, but wasn't 100% straight forward (details below).

2/ I want to open up the discussion on "strut brace theory" esp on whether the bar should be installed stressed or unstressed in tension or compression.

3/ I want to make some comments for the less experienced among us who may be getting one of these to make sure they don't make some n00b mistakes.

I came across 2 issues with the installation of mine. First is that it wouldn't fit with the car at rest on the suspension. My struts were too close together. I had to jack the car up until there was no weight on the suspension at all before it would fit. My theory on this is that at rest or driving in a straight line the forces on the struts push them closer together. (ie a strut bar would be in compression) and so over time they have moved closer together (by about 10mm at a guess!). Under cornering the opposite would be true, so over time a race car may notice the struts moving further apart.

What this means is that at rest my bar is under compression, and that I have probably reduced my negative camber slightly. I'm booked in to have new tyres fitted tomorrow, so I'm going to get a wheel alignment too and I'll let you know if it made a difference, and how much. (I keep all my alignment sheets so I can see how much it's changed with various mods)

The other issue with these braces is their fitment on the strut tops as the tops aren't flat. I've read that others have packed the gap with washers. I think it's important to mention here that you shouldn't over-tighten the nuts on the strut tops as you can stretch the bolts (especially now there is more length of free thread below the nut). This could cause the bolt to shear in certain conditions.

So what I did was just mount the bar straight on the tops and tightened to the correct torque (16ft-lbs). I checked the third nut too and it was the correct torque from when I last had the struts out. I then lowered the car onto the gorund and re-checked the torque. I got another 1/4 turn from each of the nuts hold ing the bar on. I also noticed that the gap between the bar and the strut top was now quite small as the ends of the bracket had bent ever so slightly and the lumps on the strut top squashed slightly too.

Then I went for a decent drive. Came home, (and this is the important bit for newbies) and I re-torqued the nuts. Again I got 1/4 to half a turn on each nut as the drive had allowed everything to settle a bit. The gap between the strut top and the bottom of the brace mounting bracket is now nearly zero. I expect after another long drive I should be able to get them fully down.

So the take-home lesson here is check the nuts after a few miles to make sure they haven't loosened.

In terms of handling difference - I beleive there is some over and above placebo effect. The car seems slightly flatter in the corners, loss of front grip appears like it is slightly more progessive, and turn-in seems to be better. Some of this may be due to the camber change rather than just the extra stiffness, but at the price of these bars it's worth it. I don't think you could justify spending large on a more expensive bar though. Gains are small. Cosmetically they look good too. At least 15HP.

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Juts put mine on when the car was up on axel stands, sits flat, it won’t sit anywhere near the strut top cut outs, looks fast as.

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How many kms on yours Apex? Mines approaching 250,000. Sounds as though your struts are 15-20mm further apart than mine at the top.

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i was always told when fitting one to take the weight off the towers.

i've heard of people using a turn buckle and pushing the towers out before fitting the brace.

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I didn't jack the car up before installing the brace. It just fitted perfectly. While I could put it straight on, I found it interesting with Peters '95 36 he had to jack it up.

And the strut bolts can snap if you over do it!

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Guest Simon*

So how is the tension on it now Nick? Has it loosened up (or have the nuts) with driving since you installed it?

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How many kms on yours Apex? Mines approaching 250,000. Sounds as though your struts are 15-20mm further apart than mine at the top.

Mine is approaching 250,000km too, mine is sitting on the furtherest point from center if that makes sense, the car had been on stands for two weeks though.

Posted Image

I hadn’t driven the car properly for 4 months so a before and after performance rating is hard to give, especially since I have been driving a car that’s 1000+% stiffer than the E30 for that time.

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Goes to show that there is actually a shitload of flex in the old girls.

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I'll try fit mine when I get my car back next week. Though mine has been sitting undriven for a long time and it's engineless, Probably means the strut towers aren't too stressed.

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I'm interested in seeing how your wheel alignment goes graham.

i'm having issues on the race car with front camber. It seems that Pukekohe and Manfeild with the big right handers have moved the front left strut slightly resulting in less negative camber. (approx 1.5deg down from 2deg)

Remembering that the car has a roll cage welded to the front struts this is a fairly decent change.

My dilemma is - how do i go about getting the camber back to -2deg on my left front strut. Short of adjustable mounts which are not legal or putting the car on a chassis machine?

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You would need an engine in it John to check it properly. Theres no weight without the engine.

The one I have is adjustable, I jacked up the car, adjusted the bar for the holes to line up, put 3mm tension on it, then put the car back on its feet. After the wheel alignment I really couldn't feel any difference. To much rubber in all the suspension mount points.

Looks good though.... must be at least 20 hp upgrade

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My dilemma is - how do i go about getting the camber back to -2deg on my left front strut. Short of adjustable mounts which are not legal or putting the car on a chassis machine?

Autolign can jack it back for you Ollie... talk to Ian... Carbine road brach

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Autolign can jack it back for you Ollie... talk to Ian... Carbine road brach

do you think once i have sorted the camber it would be a good idea to put a brace on? (in addition to the 8 point roll cage) or will it be a waste of time and money?

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do you think once i have sorted the camber it would be a good idea to put a brace on? (in addition to the 8 point roll cage) or will it be a waste of time and money?

Are you allowed to in the series ? I'd ask Ian that as well, but you'd need a good quality brace... not a bling one like mine

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If it doesn't fit while 'loaded' (struts too close) why not jack it up, fit the strut bar over the bolts then jack it down so they move together again and wedge up and load the bar then tighten it?

TBH I got mine more for looks than anything, How ever it fits is how it'l fit I'm not at all worried..

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Ron, there is no doubt that the camber will have changed. And as you probably know, you can't alter camber on e30's without adjustable strut tops, so an alignment won't put it back. For me personally this is a good thing. There was too much neg camber for tyre wear. Yes neg camber is good for handling (in most cases), but I'm happy with half a degree less neg camber.

The car is 20 years old. Old cars will show this kind of change and the cost to"fix" outweighs any possible gains. It's interesting to see the extent of the change though. Wheel alignment figures will be interesting too. Not much rubber left in my vehicle either, but the strut tops still are so they may pick up the slack.

I don't think there are any "problems" with the car either. Obviously there is some flex that the bar is helping to remove. Any problems would show up in a wheel alignment. As I get one every 6-12 months, in the case of my vehicle I know there aren't any issues.

My research tells me that ideally the brace should be mounted stress-free. But there are various schools of thought on this. Mine ended up being installed with some compression. But it's a moot point really.

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Would have thought that, with the shape of that (and other) braces, that the car is probably pretty close to the same shape it was before it was fitted.

It'll be interesting to see how much the alignment has changed Graham.

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So how is the tension on it now Nick? Has it loosened up (or have the nuts) with driving since you installed it?

Sorry mate, didn't see your post.

No. I did re-check it a couple times, but each time needed very minor adjustment. But its been fine ever since, hasn't loosened.

However I haven't torqued it like Graeme has. I did it hand tight as that was what was recommended to me.

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Probably a silly question, but if you put a strut brace on and it changes camber by say 0.5degrees,

when you go to get a wheel alignment, wouldn't the person doing the alignment just set the car back to factory settings and therefor eliminating any camber advantages you would have gained from the strut brace?

Same thing goes for putting offset bushes in, wouldn't the alignment guy just put it back to factory settings?

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No because these are not adjustable on e30. you can only adjust front toe unless you have installed adjustable plates/bushes.

Besides, if it were adjustable, you could instruct the mechanic (or have them advise you) what to set it to for the desired results. Factory settings are fine for unmodified cars, but lowered suspension, etc changes things.

If you could just set it to whatever you wanted, there would be no need to buy offset bushes and so on.

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I didn’t know that, they look to have quite a bit standard, well for a road car, mine does anyways. Will lowering it increase front camber at all?

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Yep, but not sure of exact amount. Maybe around 1 degree.

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Sweet, because mine was way off speck and I was wondering why if it was non adjustable, handles well either way.

Can’t wait to get out and test the brace across my favourite local backroad, should show if there is a stiffness increase as they are a good real world suspension tester, all within the speed limit of 100kph. Take Ponga up to Hunua and back to Papakura, BMW's love it!

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