Ok the other night I lost controle of my vehicle in the rain, and long story short, I am going to be converting the rear suspension to something track worthy. So far I know I am going to go with adjustable rear lower controle arms, RTAB's (polyurethene), and RSM's with the GC units. What does everyone thing is the nicest set of Rear lower controle arms, that are adjustable. Also, I am going with a full stainless steel brake line kit. My car is going to be turned into a track car, slowly but surely so comfort is not a concern of mine.

I guess if I am missing any key componants to upgrade the rear suspension, give me your opinions.
PS, Swaybarbarians are on their way.

So it's the suspension to blame for losing control?

A fresh bone stock rear suspension is perfectly track worthy. I think we need a little more info on what you are trying to accomplish rather than just asking about track worthiness.

Your gonna improve the rear suspension that much because of driver error? I hope you know that it was YOU who lost control of your car and wasnt because of the rear suspension. Anyway, I'd do the stock RTABs and go w/ the GC shims. Replace the RSMs w/ GC units or even Rogues. Why do you need rear lower control arms? Are you lowered considerably and need to adjust camber?

If anything I'd say the rear suspension is more "track worthy" than the front suspension is on an e36 :dunno . Don't blame the suspension for you losing it.

jumping to conclusions are we. I realize it was driver error, but why not improve damaged componants. christ you people are quick to jump to conclusions. and it was the rear suspension that was damaged. nothing happened to any other part of the car. a slight mistake, happens to everyone.

jumping to conclusions are we. I realize it was driver error, but why not improve damaged componants. christ you people are quick to jump to conclusions.

You never mentioned you damaged suspension components. You just said you lost control (ie: spinning out and not hitting anything) Like I mentioned, put in new OEM RTABS along w/ the GC shims and new RSMS. I'd replace the lower control arms w/ OEM ones unless your lowered and need to adjust camber. Also check out the trailing arms themselves for damage. Did you hop up on a curb or what? Knowing more details will help us diagnose what could have been damaged

You never mentioned you damaged suspension components. You just said you lost control (ie: spinning out and not hitting anything) Like I mentioned, put in new OEM RTABS along w/ the GC shims and new RSMS. I'd replace the lower control arms w/ OEM ones unless your lowered and need to adjust camber. Also check out the trailing arms themselves for damage. Did you hop up on a curb or what? Knowing more details will help us diagnose what could have been damaged


thats exactly correct. slammed drivers side rear wheel into curb which smashed lower controle arm like an accordian, I need wheel bearing, half shaft, wheel, brake line, lower controle arm so far, my car is at a local bmw shop who is on the same page as me which is to turn the car into a track car. the reason im thinking of going with an adjustable lower controle arm becasue currently the car isnt lowered, but in the near future I'd like to upgrade to some nice tck double adjustment coilovers.

Actually, Poly RTAB's could make the rear of the car more difficult to control, some of the flex in the stock ones helps correct for inconsistant input.

Hey, not a big deal everyone wipes out now and then. Putting a 6 month old pristine M Roadster over a grassy knoll and through a water main was my wake up call I needed to learn how to drive. :eek:

I am just happy that my diff didnt suffer from the lateral impact, but from what I understand, the M3 diff is tank and can take just about anything, when it comes to impact damage.

And for the record, it doesn't mean that a guy doesnt know how to drive if your involved in an accident. A favorite saying from back in Psychology 101, "Correlation doesnt equal Causation" I made a mistake, and I came on here to get advice for the route that I've decided to take, not to listen to criticism from people on the other end of the country who don't even know me.
Thanks alot!
Michael

Well keep in mind we only have what you have written to go off of, so if you aren't explicit in what you write, people are going to jump to conclusions in order to fill all the gaps you have left for them.

Anyways, all of the adjustable RLCA's look more or less very similar to eachother (meaning GC's, Turners, TCKlines). Some have heim joints connecting them to the hub assembly, and I am sure you can select different bushings as well, depending on how harsh you can stand things back there. Perhaps since you are in there anyways, you can swap in the Euro m3 rear subframe to fit a big case diff (ie. you can perhaps run the e46 m3's variable locking diff ;) ).

Some of you guys need to try Midol if you're gettin' crampy.

I didn't have a problem figuring out he wanted to upgrade as long as he was having to do repairs.

Michael, the GC adjustable LCAs are very nice. They are also legal in BMWCCA if you ever decide to go that direction. The GC articulating ride height adjusters are very sweet too. Even if you haven't gone to coilovers yet, you can still do the rears with race springs if you want to get a headstart on it.

Jay

hey if it's not too late I'll do all the labor for half the rate that the dealership is charging.

Stock LCA's are fine, they only bend when you go off hard or hit a curb (as you've found out). That is a safety feature so you don't destroy the rest of the suspension/subframe/chassis.

RTABs, don't use urethane. The stock RTABs allow a little more axial flex when coupled with huge rear tires and wider offsets, so getting RTAB shims/limiters is a really good idea.

#1 priority is to replace all the upper and lower outer balljoint pivots for the upper and lower control arms. These are the $50 balljoints that press into the rear trailing arm above and below the wheel bearing area. Replace them all, at least once a racing season. These things see quite a lot of load, up to 10,000lbs, and wear out, causing camber changes under cornering and a generic sloppy feeling from the rear suspension. The upper mount not only sees more load from cornering, but it also carries the spring load as well.

hey if it's not too late I'll do all the labor for half the rate that the dealership is charging.

I've got Simpson doing the work for me, although I appreciate the offer. BTW, nice 97+ kidneys.

Hey jamesm3m5
I was just at your website, and I was wondering what are the differences in your performance wheel bearings? because I know that will be something I will have to replace. and any deals for us bf.c members?:) :)

Well keep in mind we only have what you have written to go off of, so if you aren't explicit in what you write, people are going to jump to conclusions in order to fill all the gaps you have left for them.

Anyways, all of the adjustable RLCA's look more or less very similar to eachother (meaning GC's, Turners, TCKlines). Some have heim joints connecting them to the hub assembly, and I am sure you can select different bushings as well, depending on how harsh you can stand things back there. Perhaps since you are in there anyways, you can swap in the Euro m3 rear subframe to fit a big case diff (ie. you can perhaps run the e46 m3's variable locking diff ;) ).

I'd like to hear more about this, has anyone on here done this and with what serious advantage is this going to have? I mean, I would expect this to be on the more expensive side of the spectrum and I just wonder if there are serious gains made by doing this.

Not even considering doing this but would be interested in learning alittle bit about it.

I'm not sure there would be any advantage to going with the big diff...besides adding more weight that you don't need. People are running tons of power through the small case diff without any problems.

As for the E46 M3 diff...most folks who race those cars end up going with a more traditional limited slip and ditching the variable locking diff.

yeah, I was pressing my mind to think of a reason that this would be worth the thousands of dollars spent on swapping rear subframe and diff to one of greater complexety........but I couldn't think of anything.:eyecrazy

Ladies and Gentlemen, I just picked up a steal of a deal, I just got the TCKline aluminum adjustable rear lower controle arms used off my mechanics LTW race car, and they have no more than 200 miles on them he said. They are the ones with the solid bushings, and I picked them up for 150 dollars. That is a deal if I may say so myself.

While you are at it, I would replace the outer upper control arm rubber bushing with the solid kind found on the outer lower control arm. If you pull the rear subframe, replace those bushings and while you are there throw on some solid diff mounts as well. I hope you are replacing the front brake lines with SS as well, and if you are, replace those rubber caliper bushings with the solid brass guides. The list is endless, you need to have and end goal in mind or you will constantly be replacing things.

RTABs, don't use urethane. The stock RTABs allow a little more axial flex when coupled with huge rear tires and wider offsets, so getting RTAB shims/limiters is a really good idea.Why not urethane? What about delrin?

I am using the stock RTABs with the GC shims (mostly street car), but I'm just curious about your opinions on the other stuff.

And what about urethane or delrin on the front control arm bushings? One day I will get around to replacing the front control arm bushings, but I'm not sure whether to stay stock (96+ centered with the cutouts), use the 95 solid offset bushings (increases caster and ??), urethane, or delrin. I'm assuming the last two are going to increase NVH some, not sure how much.

I second James and his suggestion to replace the upper and lower control arm bushings. Both inner and outer. But I don't remember there being any ball joints back there. The lower outer bushing is what the stock eccentric bolts through. Just remember that when you replace those disposable stock lower control arms with those nice TCK arms you are giving up the safety factor of the stock ones. A second incident like what you have just had will probably damage the diff or subframe mounting points. Just FYI. Those bushings have to be pressed in and out and I would think can only be done off the car. If that stuff is off the car and you are taking the other side off to make them symetrical then I would go ahead and drop the diff and subframe and put the Turner reinforcements on. Also check your trailing arm mounting points for issues with the threaded inserts. The three bolts that hold the RTAB carrier on the car screw into threaded insrts welded into the chassis. There have been reports of finding these inserts only tackwelded in spots around their circumference. Most cars have a continuous weld all the way around. But it is worth checking on. Just my 2 cents.