RTAB options for rear subframe with Camber/Toe adjustment

[Frog]

I am installing camber & Toe AKG adjustments on my e30.. I heard that using solid RTAB bushings was bad since the trailing arms were in a 'bind' after adjustment, and that this bind affected suspension geometry.

I was also told that I would need to use stock rubber bushings to accommodate for that..

Please enlighten me here.. I have solid RTABs ready to go in but now I don't know what to do.

[SkiFree]

If I've heard how many times, "I heard it on the internet...". If you want to scare yourself some more .... see here....

http://forums.bimmerforums.com/forum/archive/index.php?t-1799320.html

[mr2peak]

Yes they do bind with AKG bushings. Very, very hard to move by hand with the correct toe/camber settings. Just use stock bushings, the offset will take the slop out of the pivot.

[LowR3V'in]

so with the solid akg trailing arm bushings you can't use the
slotted correction plates because they don't have any play it or
whatever the reason?

I really wanted to use these plates but after hearing the toe adjustments always
pop out of place and now this :( Forever hella stanced. :(

[SkiFree]

Well if your knowledge source is limited to the internet rather than first hand tinkering; then yes, you're going to be limited.

As an opposite point, been running the ie/ie combo for many years, most recently was last weekend out at Pahrump finished a full weekend of racing without issue.

[LowR3V'in]

So mr2peak is big liar?

[SkiFree]

What, how are you coming to that conclusion?! If only I was naive enough to believe everything in the world was so black and white. Right and wrong, liar and truth teller. There's more than one way to skin a cat, I'm telling you what has worked for me.

[mr2peak]

So mr2peak is big liar?

Lol

I installed the E30Tech stuff myself a few years ago, and had a very very hard time moving the trailing arm by hand, it was partially bound with the AKG bushings. Can I deliver the force of a 400lb spring or a 2,700lb E30? Hell no. So is it critical? No. But it is very far from ideal, and getting it ideal is what car tuning is all about.


After that experience I will be doing it differently on the next E30 I build. But hey, do what you want.

A tube based trailing arm with spherical bearings and an X1/9 style hub would be the shiznizzle..

[Frog]

If I've heard how many times, "I heard it on the internet...". If you want to scare yourself some more .... see here....

http://forums.bimmerforums.com/forum...t-1799320.html

I have not heard from the internet, but a local e30 racing parts manufacturer.

Yes they do bind with AKG bushings. Very, very hard to move by hand with the correct toe/camber settings. Just use stock bushings, the offset will take the slop out of the pivot.

Really bums me out to use the stock rubber when the entire rest of the suspension has Solid Derlin.

Are there any spherical bearing options out there?

[LowR3V'in]

There was this.
It was pretty cheap too. :(

http://www.e30tech.com/forum/showthread.php?t=73046

[SkiFree]

I have not heard from the internet, but a local e30 racing parts manufacturer.


Really bums me out to use the stock rubber when the entire rest of the suspension has Solid Derlin.

Fair enough, the IE RTABS are around a 90a urethane hardness, and I've found them to have just enough give on our race cars running adjustable rear ends.

Even among "experts" results will vary.

[deutschman]

I have not heard from the internet, but a local e30 racing parts manufacturer.



Really bums me out to use the stock rubber when the entire rest of the suspension has Solid Derlin.

Are there any spherical bearing options out there?

I dont know what people are talking about. I had the IE weld on camber and toe adjustments on my 2002 with urethane bushings with no problems, and I have the same IE parts on my current e30 with the solid Condor Motor Sport bushings and they work fine. Get them welded on correctly and you will be fine. Is it a perfect solution? Maybe not but its the best unless you want to fabricate a M3 DTM stile rear suspension which is going to cost you a LOT of money.

[LowR3V'in]

I just bought a set of cam/toe plates, kinda expensive

but I guess I'll trust the guy who actually works for IE who says
they won't bind my bushings. I'll post a review vids and stuff when I adjust them.
excited to get some hella flush stance out of my rear. :)

[SkiFree]

Your call, just bear in mind that a lot can also depend on the ability of the installer. Be sure to get the alignment specs prior to taking everything apart. This will help you preposition the plates where you'll need them to keep the amount you end up skewing the bushings at a minimum.

[jalopi]

I don't really see what the issue is, though I haven't gotten a lot of sleep this week and might be reading everything wrong.

Suspension bits aren't really supposed to be able to move easily by hand... if they do something's probably broken or loose as shit. When I was still working at a shop I did run into cars that had slotted adjustments for camber/caster or rear toe and there was no way I was adjusting or moving that shit by hand, even if I jacked the wheels up. 2 foot prybar at the minimum.

Just remember, it might not be so easy for you (a person) to move a suspension part (maybe even more so if the new bushings are giving you some resistance) but the 700ish# static [and whatever it is dynamically] weight of that corner of the car will move the suspension just fine :)