H&R Race springs spring pad questions...

[digger]

I redid my string setup and it's all good. My strings weren't parallel to each other showing it being toed out.

i have had 3 alignment checks done by shops (laser or whatever they fancy machines that they all use) and they all showed notably different results at the rear though two are somewhat consistent. i had to use a string line setup to be able to do a sanity check to work out which was more correct. It could be that with semi old bushes the thing does move around so there could be some variation but tbh i dont know how much is normal variation so i am not even 100% sure whether how i set them will be able to get it proper as the lingering doubts caused by different values. I know for sure they are atleast toe out as all show this as does the string line method

[zaq123]

I redid my string setup and it's all good. My strings weren't parallel to each other showing it being toed out.

[digger]

strangely, I had it dialled ion perfectly when it was lower. I'm gonna see where my camber is at now because I think the camber adjuster has something to do with the toe being where it's at now.

looks like camber and toe plates do interfere with each other.

http://e30sport.net/tech_articles/ecc_bush/ecc_bush.htm

The two are always lightly coupled because the pivot axis is 15 degrees from a perfect transverse axis. if the axis was perfectly transverse then adjusting camber would not affect toe one iota

That article appears to refer to offset bushings (kmax dont have these anymore? but powerflex and superpro still do them) which by virtue of the way they work by rotating the pivot axis about the factory pivot which ends up moving the pivot axis horizontal and vertical. The eccentric bolts don't do this anywhere near as much as they simply translate either up and down or fore and aft depending on orientation and thus and cross coupling is only related to the 15 degree factor.

[zaq123]

I dont think that lowering is going to correct 1mm per side without adjusters based on the numbers in e30sport.net

you can of course add 1mm offset OE rubber bushes (outer or inner/outer) if you don't want to add plates/eccentric bolt
or
the eccentric aftermarket pins with concentric poly bushes may be enough

strangely, I had it dialled ion perfectly when it was lower. I'm gonna see where my camber is at now because I think the camber adjuster has something to do with the toe being where it's at now.

looks like camber and toe plates do interfere with each other.

http://e30sport.net/tech_articles/ecc_bush/ecc_bush.htm

[digger]

All subframe bushings are OEM. Rear ride height is 305mm now. I raised the suspension to OE Sport from Sport springs and ended up with 0.13 toe out on both sides (both sides have equal 1mm toe out on the string). Didn't measure camber yet. My previous setup when was slightly lower than now was zero toe and 1.8' (1'48") of equal camber on both sides (rear camber plates almost maxed out) . Id like to go back to zero toe. No toe plates, wonder if my camber plates will dial some toe as well since my camber is now is even less negative. I can also throw in 15mm rear spring pads in the back if it helps. That will bring my rear to 310mm?? (proportionate)?? ride height (I have 10mm pads now)

I dont think that lowering is going to correct 1mm per side without adjusters based on the numbers in e30sport.net

you can of course add 1mm offset OE rubber bushes (outer or inner/outer) if you don't want to add plates/eccentric bolt
or
the eccentric aftermarket pins with concentric poly bushes may be enough

[zaq123]

it will toe in very slightly on compression but gain more camber

if your toe is ok now then it should be fine but excess toe in now gets a bit worse or if you have some toe out or straight then it wont change significantly to correct a "major" issue

what is your ride height centre of wheel to arch ? and what change are you looking for?

All subframe bushings are OEM. Rear ride height is 305mm now. I raised the suspension to OE Sport from Sport springs and ended up with 0.13 toe out on both sides (both sides have equal 1mm toe out on the string). Didn't measure camber yet. My previous setup when was slightly lower than now was zero toe and 1.8' (1'48") of equal camber on both sides (rear camber plates almost maxed out) . Id like to go back to zero toe. No toe plates, wonder if my camber plates will dial some toe as well since my camber is now is even less negative. I can also throw in 15mm rear spring pads in the back if it helps. That will bring my rear to 310mm?? (proportionate)?? ride height (I have 10mm pads now)

[digger]

ok I forgot what I did, I installed only camber plates in the rear, not toe plates. Figured it will slightly toe in on the mild drop but the camber would be more affected hence only camber plates....was I wrong? Let's say I pull trailing arms up on the camber adjusters up to get the camber in spec? Will arm geometry affect the toe in the neg (toe-in) or positive way (toe-out)?

it will toe in very slightly on compression but gain more camber

if your toe is ok now then it should be fine but excess toe in now gets a bit worse or if you have some toe out or straight then it wont change significantly to correct a "major" issue

what is your ride height centre of wheel to arch ? and what change are you looking for?

[digger]

This might help ?

https://www.e30sport.net/tech_articles/susp-tech/rear_curves/index.htm

[zaq123]

i am running GC setup on rear so adjustable 2.5" perches 650lb springs 6" long. The most pertinent info is that it is a series 2 and ride height @ rear is 303mm centre of wheel to arch

ok I forgot what I did, I installed only camber plates in the rear, not toe plates. Figured it will slightly toe in on the mild drop but the camber would be more affected hence only camber plates....was I wrong? Let's say I pull trailing arms up on the camber adjusters up to get the camber in spec? Will arm geometry affect the toe in the neg (toe-in) or positive way (toe-out)?

[digger]

digger, what springs are you using? On my rear subframe. I only installed toe adjusters when I was redoing my suspension (OEM BMW eccentric bolts kit). I placed toe adjusters in the middle and was at zero toe just as they ran out of the adjustment. I have H&R Sport springs with 10mm rear OEM spacer. Going to H&R OE Sports with 15mm E46 rear spring pad. We shall see.
Also I.m using these guys alignment tool (link). Had to buy some aluminium tubing for it and I/m using 20lbs braided fishing line as it's only 0.3mm thick and gives very accurate measurements. I got a bunch of those plastic kitchen thin cutting boards for wheels when doing the adjustment to keep wheels traction free. They are so slippery that I can slide the car sideways on them.

https://calipergarage.com

i am running GC setup on rear so adjustable 2.5" perches 650lb springs 6" long. The most pertinent info is that it is a series 2 and ride height @ rear is 303mm centre of wheel to arch

[zaq123]

digger, what springs are you using? On my rear subframe. I only installed toe adjusters when I was redoing my suspension (OEM BMW eccentric bolts kit). I placed toe adjusters in the middle and was at zero toe just as they ran out of the adjustment. I have H&R Sport springs with 10mm rear OEM spacer. Going to H&R OE Sports with 15mm E46 rear spring pad. We shall see.
Also I.m using these guys alignment tool (link). Had to buy some aluminium tubing for it and I/m using 20lbs braided fishing line as it's only 0.3mm thick and gives very accurate measurements. I got a bunch of those plastic kitchen thin cutting boards for wheels when doing the adjustment to keep wheels traction free. They are so slippery that I can slide the car sideways on them.

https://calipergarage.com

[Northern]

I think most rear subframe riser bushings are 12mm (+12mm diff spacers to bring the diff back down)

If you mean engine mount spacers, I don't know. I bought some aftermarket engine mounts that were supposed to be stock sized, but they ended up being hilariously tall and unfortunately created more issues than they solved.

[Vincent Vangool]

Agree with the high pressure gas billies making the car ride stiffer. I think Konis and H&R Race should be a good combo, but I always tried to get the front lower and would bottom out my H&R Race setup. As long as OP is not trying to be 2010-era hellaflush, he should be fine.

I'm also somewhat anti-skidplate... I ran raised motor mounts and never blew up an oil pan. Skidplate will definitely add some protection, but I think it also creates a feedback loop where it makes the lowest spot of the car lower -> you hit more stuff -> you are thankful you have a skidplate because "look at all it protected me from"y c

I'm a big fan of the subframe risers. Maybe something is wrong with me/my car, but my wear was never bad on H&R Race even before subframe risers. Not a fan of the common adjustable subframe stuff due to slip and how many people seem to weld them on in a way that doesn't allow enough adjustment.

I'm not going for 2010 hellaflush, hahaha. What mm risers would you put front and rear on this to get it to a good right height where I'm not smacking the pan? Mostly concerned with the front for now, as the rear will be easier to take apart and fine tune later. Any suggestion on front or rear sizes to accomplish this is appreciated.

Any idea what size pads an 89 325is came with from the factory?

[digger]

From my research i am seeing for the rear on a RWD street car
- around +2 to +3 mm (-0.080" to-0.125") total toe equivalent for ~16"
- around -1* to -2* degrees camber

the Bentley manual says
- +3 mm +/-0.8 mm total toe (M-tech)
- +2.6 mm +/-0.8 mm total toe (325i)
- -2.5* +/- 0.5* (M-tech which seems high as i am 2.25* when quite a bit lower than factory mtech)
- -2.25* +/- 0.5* (325i)

Probably not going to matters much if you are somewhere in the range. You probably need to be way out to lunch or probably more importantly left to right imbalanced or suffering massive tyre wear to notice. Somewhere in that range is a start point.

Mine has like a slight toe out atm and >0.5 degree LH to RH variation so hoping to notice something by rectifying that.

[McGyver]

Thanks. I am going to aim for about 1.0mm toe each side (supposed to improve stability c.f. zero toe or a bit toe out) and maybe 1 degree neg camber (improve inside edge tyre life), i hope my alignment shop gave good numbers and that the bushes werent flogged out enough to affect the validity of measurements.

When swap in the new engine (after I finish building it) I planned on re-doing the rear adjusters. I'll take it to an alignment shop to get the current measurements, maybe even get some measurements at different ride heights by swapping in some spring spacers I made. That should give me a good idea of how the alignment changes over a range of heights. I still need some advice on ideal alignment specs for street driven car that may see some occasional twistys or auto-x. I want the adjusters set up to allow for some actual adjustment, not just max out on removing negative camber and toe-in to get it close to good.