Which camber/toe kit for rear?

[rev29k]

Hello folks.

Been trying to research this on my own and I'll admit I'm not having any luck identifying a kit to order to be able and adjust my rear suspension. I thought it was just replacing the standard bolts with eccentric ones, but then I see other kits, etc. and I'm starting to get lost.

All I am looking to do is be able and take my car into an alignment shop and for them to be able and align it. Especially the rear. I know the Stealer uses weights to simulate load, but there's hardly ever any load on the rear (just wife and I) and so WITHOUT any load I am always driving around with the rear out of spec.

Can anyone suggest any decent kits that I can order and have installed at my mechanic? I would greatly appreciate it.

[rev29k]

So I think I have a slightly better understanding. Are the rear camber eccentric LOCKOUT kits the only thing that is available? I ask because those seems to require adjustable upper/toe arms as well.

Or is there an option for just a regular eccentric bolt set that isn't "lockout" that doesn't require replacing the upper arms?

I believe this is correct, but if it isn't the case please feel free to correct me.

TIA!!

[rev29k]

Beuller!!!

[jfritz27]

If you're looking for a standard alignment, you can do that without doing anything to the car. Camber and toe is adjustable within a certain range in the rear. Even for track use, the stock camber range is generally sufficient (you can get -2, which is a good amount for most people). If for some reason you need a lot more, then you may need to swap out for adjustable arms. Adjustable toe arms can make the alignment process easier but aren't strictly required; they may be needed at higher levels of negative camber if you want to simultaneously get enough toe-in.

[rev29k]

Shop I went to says they can't adjust the rear into specs, they need more adjustment. Which is why I was told to get replacement eccentric bolts to allow for more adjustment. Not sure if they are just dumb or what. I hardly drive the car, certainly don't track it. Just spirited driving here and there or maybe a nice road trip.

Are you saying it should be adjustable to within specs even without the weight bags the dealer uses?

[Ant_tc]

Lowered or stock height?

[x.shell]

Originally Posted by rev29k

Shop I went to says they can't adjust the rear into specs, they need more adjustment. Which is why I was told to get replacement eccentric bolts to allow for more adjustment. Not sure if they are just dumb or what. I hardly drive the car, certainly don't track it. Just spirited driving here and there or maybe a nice road trip.

Are you saying it should be adjustable to within specs even without the weight bags the dealer uses?

The OEM rear suspension has sufficient toe and camber adjustment. The rear lower control arm already has an eccentric bolt to adjust camber. You can get up to -2.5(ish) degrees of camber with a slight toe-in if your car is lowered a little bit. Stock height can probably yield -2 degrees of camber no problem. I don't know why anyone would want more negative camber than that for the rear. If you want more toe adjustment, you can just get an adjustable rear toe arm. So many aftermarket rear toe arms are available. So many.

Now, if you want to get technical, keep reading. There are 5 links in total for the rear (per side) — toe arm, lower control arm, trailing arm, two upper control arms.

In OEM configuration, the lower control arm is solely used to adjust camber. This arm can be modified in several different ways.

(1) You can add a "lock out kit" which just replaces the eccentric bolt with a regular bolt and shims that lock your camber into place. There is no additional adjustment with these kits. If anything, there is less adjustment. It just locks the camber into preset increments. If your tech is complaining about lack of adjustment, this will not help — it'll make his problem worse.

(2) Replace the inboard bushing with an eccentric solid bushing. This will give you a massive amount of camber adjustment as you will have two points of eccentric bolt adjustment on a single arm — which you won't need. People who do this mod usually lock the outboard eccentric bolt and just use the bushing to adjust camber. Your camber will be limited by your toe adjustment range. An adjustable toe arm is mandatory with this mod.

(3) Replace the entire lower control arm. This is self explanatory. Same as (2) use an eccentric solid bushing. This mod has no more adjustability than option (2) — the benefit is having a fancier, lighter, and cooler looking arm with the outboard bolt already locked off.

Now if you really want to go bonkers…

You can also change the upper control arms to adjustable ones. This will allow you to adjust camber from the top vs bottom. This mod will certainly require you to change the trailing arm and toe arm to adjustable ones in order to keep the geometry proper.

So long story short, do you need a rear camber lock out kit? No.

On my F80, I have every rear suspension arm changed to adjustable SPL arms except the lower control arm. I do not use the camber lock out kit — that part is still OEM.

The lock out kits do not give more adjustability. They are sold with the idea of scaring the customer into thinking the OEM eccentric bolt will "slip" under high loads. If they're torqued properly, they won't. But if you still want a kit, I have a new lock out kit for sale that I never installed.

If your tech has trouble aligning the OEM rear suspension, find someone else. The rear alignment process on the F8X is the same as every modern car that uses a multi link suspension. You can literally align it yourself in your garage with string, jack stands and a ruler. There is no trickery — your guy just doesn't know how to align a car.

[TopJimmy]

…what X.Shell said… find another guy.

[rev29k]

Thanks X! That really helps me. You didn’t mention it specifically, but I presume you think there should be plenty of room to align rear toe with stock height as well, correct? I’m going to try another shop, but I was wondering if perhaps when the camber is set right then there isn’t enough play to adjust toe. But again, my take away from you is that there should be plenty of play for both camber and toe on a stock vehicle, right?!

[x.shell]

Originally Posted by rev29k

Thanks X! That really helps me. You didn’t mention it specifically, but I presume you think there should be plenty of room to align rear toe with stock height as well, correct? I’m going to try another shop, but I was wondering if perhaps when the camber is set right then there isn’t enough play to adjust toe. But again, my take away from you is that there should be plenty of play for both camber and toe on a stock vehicle, right?!

In stock configuration, you are right to assume that the toe and camber should be able to achieve it's proper alignment specs without any problems.

In multi-link suspensions, adjusting one component will affect the others. But you will only run into potential problems when maxing out one adjustable link. For example, the OEM F8X only has two adjustable links in the rear — camber and toe. If you max out camber at say -2.5 degrees (if you can even achieve that number), you won't be able to get a 1/16th inch toe-in. Your max toe might be 0. So if you want toe-in, you will have to ease off the negative camber a bit. Basically, it's a give and take. But you have plenty of range to get the factory recommended alignment specs.

If you do not have the proper range to meet spec, it's probably due to other issues like bent arms or bent subframe etc.

[rev29k]

Thanks for the help guys. I went to another shop and they had no problem aligning it. Had a feeling the first shop wasn’t right. It always pays to know as much as possible about a subject so you don’t just do whatever they suggest. Thanks again for helping me to better understand what I was dealing with.

[mikerunt]

Anyone know if to install SPL rear toe arms if you have to drop the subframe on an m4 GTS? I know you do on the M2.

[Track/S]

Originally Posted by mikerunt

Anyone know if to install SPL rear toe arms if you have to drop the subframe on an m4 GTS? I know you do on the M2.

For the m2 it is not necessary to drop, on F82 I imagine it will be same.

I hope you don't hurt yourself with spl arms.

[mikerunt]

Originally Posted by Track/S

For the m2 it is not necessary to drop, on F82 I imagine it will be same.

I hope you don't hurt yourself with spl arms.

How do you mean?

[FaRKle!]

Originally Posted by Track/S

For the m2 it is not necessary to drop, on F82 I imagine it will be same.

I hope you don't hurt yourself with spl arms.

Yes it is necessary to drop the subframe a bit on the M2. The left/driver's side bolt securing the toe arm is too long to remove from the subframe without dropping it to clear the battery compartment. The right/passenger's side has enough clearance to do it without dropping the frame.

I've seen people mickey mouse it by denting their battery compartment with a hammer to make clearance, but that's pretty crude.

F80/82/83 have more clearance between the subframe and under trunk cubby and haven't had to drop the subframe in my experience.

[Track/S]

Originally Posted by FaRKle!

Yes it is necessary to drop the subframe a bit on the M2. The left/driver's side bolt securing the toe arm is too long to remove from the subframe without dropping it to clear the battery compartment. The right/passenger's side has enough clearance to do it without dropping the frame.

I've seen people mickey mouse it by denting their battery compartment with a hammer to make clearance, but that's pretty crude.

F80/82/83 have more clearance between the subframe and under trunk cubby and haven't had to drop the subframe in my experience.

i have changed all arms on my f87 without dropping the frame and without denting anything. Just a little scratched the rubber protector of the battery compartment.

Originally Posted by mikerunt

How do you mean?

There is a user who posted pics of the spl arms and the wheel looking at china, i don't want to imagine this happening on a track

[FaRKle!]

Originally Posted by Track/S

i have changed all arms on my f87 without dropping the frame and without denting anything. Just a little scratched the rubber protector of the battery compartment.

You got lucky then. I've swapped those arms on multiple M2s where there wasn't enough clearance without lowering the subframe so the bolt can clear the battery compartment. If all it took was a bit more prying, I would've certainly preferred that.

[RsimmM4]

Originally Posted by x.shell

The OEM rear suspension has sufficient toe and camber adjustment. The rear lower control arm already has an eccentric bolt to adjust camber. You can get up to -2.5(ish) degrees of camber with a slight toe-in if your car is lowered a little bit. Stock height can probably yield -2 degrees of camber no problem. I don't know why anyone would want more negative camber than that for the rear. If you want more toe adjustment, you can just get an adjustable rear toe arm. So many aftermarket rear toe arms are available. So many.

Now, if you want to get technical, keep reading. There are 5 links in total for the rear (per side) — toe arm, lower control arm, trailing arm, two upper control arms.

In OEM configuration, the lower control arm is solely used to adjust camber. This arm can be modified in several different ways.

(1) You can add a "lock out kit" which just replaces the eccentric bolt with a regular bolt and shims that lock your camber into place. There is no additional adjustment with these kits. If anything, there is less adjustment. It just locks the camber into preset increments. If your tech is complaining about lack of adjustment, this will not help — it'll make his problem worse.

(2) Replace the inboard bushing with an eccentric solid bushing. This will give you a massive amount of camber adjustment as you will have two points of eccentric bolt adjustment on a single arm — which you won't need. People who do this mod usually lock the outboard eccentric bolt and just use the bushing to adjust camber. Your camber will be limited by your toe adjustment range. An adjustable toe arm is mandatory with this mod.

(3) Replace the entire lower control arm. This is self explanatory. Same as (2) use an eccentric solid bushing. This mod has no more adjustability than option (2) — the benefit is having a fancier, lighter, and cooler looking arm with the outboard bolt already locked off.

Now if you really want to go bonkers…

You can also change the upper control arms to adjustable ones. This will allow you to adjust camber from the top vs bottom. This mod will certainly require you to change the trailing arm and toe arm to adjustable ones in order to keep the geometry proper.

So long story short, do you need a rear camber lock out kit? No.

On my F80, I have every rear suspension arm changed to adjustable SPL arms except the lower control arm. I do not use the camber lock out kit — that part is still OEM.

The lock out kits do not give more adjustability. They are sold with the idea of scaring the customer into thinking the OEM eccentric bolt will "slip" under high loads. If they're torqued properly, they won't. But if you still want a kit, I have a new lock out kit for sale that I never installed.

If your tech has trouble aligning the OEM rear suspension, find someone else. The rear alignment process on the F8X is the same as every modern car that uses a multi link suspension. You can literally align it yourself in your garage with string, jack stands and a ruler. There is no trickery — your guy just doesn't know how to align a car.

I just spoke with Eibach about this and they said rear has lots of adjustability and that if the alignment shop has issues, have them change the toe to positive .17 (max) and that will allow more camber adjustment and give better tire wear.

[M3SQRD]

Originally Posted by RsimmM4

I just spoke with Eibach about this and they said rear has lots of adjustability and that if the alignment shop has issues, have them change the toe to positive .17 (max) and that will allow more camber adjustment and give better tire wear.

0.17 mm or in or deg? Also, is it total toe (total toe 0.17 missing unit) or toe per each side (total toe 0.34 missing unit)?