adjustable toe / camber rear beam. how to set it up? help!!!

Sat May 24, 2008 10:11 am

i've got my DIY adjustable toe / camber rear subframe fitted now, using OEM rubber trailing arm bushes and solid powerflex polyurethane subframe mounts.

the problem i've found is: i can't get to the nut on the outer (toe) adjuster once the beam is on and the tank is fitted. i've found that i can fairly easily remove the subframe mount plate jobbie, knock the stud out of the bush, drop the beam down 3" on that side, pull the top seperate polyurethane cap off the bush then get to the nut. problem being this isn't going to be ultra accurate on a tracking rig like this so i'll have to tweak / refit it several times! also, i can't tighten the nut with the weight load on the wheel like you're supposed to which as i've got OEM rubber bushes, will kill them off soon.

a way round the bush damage issue would be to fit polyurethene trailing arm bushes as they slip on the liners rather than twist like the rubber, but these are expensive and against my principles!

how has everyone else set theirs up?

i'm thinking trial and error and an hour on a ramp with the tracking gauges on should have it done but it'll be a ballache. either that or take the tank out and tow the car there but that'll be even more of a ballache!

oh, also, to start with, should i aim for factory rear toe settings or some other value?

Sat May 24, 2008 10:19 am

Hi

i have this set up on mine, however i have not used the car since it was fitted as the engine is still at A-tech.

The initial guess set up i went for was minimium, neg camber (as my car is very low) and toe as straight as possible. This has all been done by eye and some lazer alignment is probably required.

It shouldn't be a problem for me to adjust when it is on the car tho as i have a fuel cell in the boot.

Sat May 24, 2008 10:23 am

mine is was set up to a token toe correction value by eye and full positive camber setting (halfway back to standard spec). not having a tank will save you so much grief!

Mon May 26, 2008 1:28 pm

Wed May 28, 2008 2:24 am

toe in at the rear keeps the car stable, i guess that by having added the facility to adjust toe you'e not going to be sticking with factory settings.

running the rear closer to straight will make it a bit more lively, but tends o make it more progressive too. i guess it's one of those things though, not many people have done it, and those that have may want totally different things or have completely different driving styles

Wed May 28, 2008 12:51 pm

Hi I have this set up on mine (home made job), it is set parallel track and 1 deg neg of camber. Was a pain to adjust for sure but now its right I shouldn't need to touch it again.
Regards
Ray

Wed May 28, 2008 11:46 pm

cheers fellas

Thu May 29, 2008 7:16 am

Yes, adjusting toe in passenger side of the car (right side) is quite a pain in the ass. I've powerflex - bushes all around => the big bushes in the rear axle are bigger than original so i had to cut the bushes a bit to gain access to rear trailing arm outer nut.
Anyways, i had to modify one sprocket to be able to tighten the nut after adjusting.

But as said before - once you've done it you shouldn't have to do it again (well, in a track car you maybe have. But in street cars not

)

Thu May 29, 2008 10:08 pm

ta jonsku! looks like you have the exact space limitations i have!
it'll be a pain in the arse once but as you say, being a road car, it'll only be once.

Sun Jun 08, 2008 7:56 pm

an update...
using some string and laying the geometry out on CAD, i've now got my tracking set to an even level each side.

after having a measure up once it was sone, i now have 0.3° toe out each side at the rear (0.6° total) and 0.5° toe out on each side at the front (1° total)

i'll get the front done at a tyre place to get it spot on but what's the best setting to aim for on the rear? dead ahead?

Mon Jun 09, 2008 3:55 pm

what i did was go for dead ahead paralel at the rear then i tweaked to my own liking from there.... this wa you have a nice basepoint to go from

if u feel turn in is twitchy at higher speeds and oversteery then toe the rear in some more, depends how you like the handling to be as its personal preference

as for the front i always found a slight toe out worked very well on my e30, but once again to get a baseline i'd ge them set parallel and go from there

Mon Jun 09, 2008 4:33 pm

My friend has this kit . witch i may be borrowing off him as i am doing my subframe now.

just to clear up .
which side is which . doee the camber bolt and braket go onto the inside of the car or the outside ?

and what is factory settings on toe and camber for the rear. ?
also the bolts that come with the brackets , they seam to short and do not go on the bolt al the way . is this normal not to cover the treads 100 percent

Mon Jun 09, 2008 6:29 pm

Camber on the inner brackets with slot verticle and toe outter with slot horizontal.

I had the same problem and 'm also a little worried, however i slapped a load of loctite on them and did it as tight as i could.

my plan is to check them on a regular basis.

Mon Jun 09, 2008 10:49 pm

cheers karan, dead ahead for the time being then. i've got to re-learn the car before i decide how to set it up, it's spend most of it's time off the road over the last few years

regarding bolt length, mine are all fine and cover the threads totally, though i did machine the guide plates a bit thinner. the correct nuts are crimped self locking types so do really need to be completely filled with thread.

Tue Jun 10, 2008 9:19 pm

ok, i've had a more accurate measure-up and tweaked a bit from there as the car wasn't on a totally level bit of ground before. also used fishing line rather than string this time!

my rear figures are 0.25° toe out n/s/r, 0.30° toe out o/s/r.
obviously this is well out of factory spec but how does it compare to figures people have tried? as i have yet to swap the o/s/r trailing arm at a later date for one with an ABS sensor hole ( whoops

) i think i'll leave it as-is for now. it's certainly better than before i started

karan, did you measure yours once set up?
incidentally, due to the wider track on the front , the factory values are 1mm of apparent 'toe in' (using the string method) over the wheel to achieve a true 0.06° toe in (per wheel)

Wed Jun 11, 2008 9:39 pm

I dont think you will get on with toe out on the rear for sure, it needs to be either parrallel (which is alittle twichy) or toe in which makes it more stable ( toe in 0.24 + or - .07 standard) the more toe in you have the more stable it gets. My car is parrallel & follows the humps & bumps in the road abit but not bad. I think I will put abit of toe in when im next messing about with the rear suspension. I have used toe out on the rear of a car to try to get more oversteer it was frightning over 70mph.
Regards Ray

Wed Jun 11, 2008 10:14 pm

cheers dude, one final tweak is in order then

ho hum, it 'only' involves dropping the subframe... neverending tinkering

Thu Jun 12, 2008 9:33 pm

one final tweak now completed

i'm getting quick at this! i can drop both sides, measure, adjust and rebuild then check again in an hour now!

now i have:
0.08° toe in n/s/r
0.07° toe out o/s/r

so other than crabbing by 1mm at the rear, it's set dead ahead-ish

that'll do me for now methinks

Thu Jun 26, 2008 10:55 pm

hi mate.... how does ure car drive now compared to before? and what camber have you acheived?

Fri Jun 27, 2008 12:48 am

much more stable at speed and very well balanced. it's been round the ring now and handled better there than ever before on the road, nice and easy to balance the car on the throttle mid corner. if anything, i found it a bit understeery but i didn't play with shock settings and did lap with a LPG tank, tools, jack etc all in too so the arse is quite heavy!

i've not measured the camber, though i guess it's near stock again, i'll have to check soon.