GC camber plates now available ... - The Unofficial BMW M5 Messageboard (m5board.com)

EdP · 8th September 2004, 16:18

.... at least according to their new website. http://www.ground-control-store.com/ Who's planning to buy? I've been going back and forth on getting camber plates vs. full suspension upgrade vs. nothing for now and sorting out the options in the Spring (I'll only do 2 more track events this season, and it'll be the first time I've tracked the M5).

Aside from the availability of better alternatives, are there any downsides with using adjustable camber plates? For the first-time user, are they relatatively idiot-proof and easy to adjust, or can I expect a learning curve dotted by expensive mistakes? One person I spoke with suggested that fixed plates (i.e., Dinan) were better because adjustable plates could become "loose" -- his explanation was not clear to me.

Thanks in advance.

CSBM5 · 8th September 2004, 19:57

Most of the camber plates (K-mac, Dinan) raise the front ride-height by their thickness, so that is a potential downside to doing just plates. From a post by Lscman, I think he stated that the K-mac would add 3/8" to the front ride height. My conversation with Dinan indicated that their plate was around 1/4" thick as I recall.

After driving Redshift's M5 last night with the GC coil-overs (which come with the GC camber plates), I'm sold on the GC solution I think. Given that one of my biggest concerns was ride compliance, we took it over some pretty nasty stuff, and it was very well behaved.

Re the plates coming loose -- if they are properly designed, installed and adjusted, I wouldn't think that would be an issue. Changing the camber angle however of course changes the toe-in. On the M5, the tie-rods are behind the wheel centerline, so when you add negative camber, you get more toe-in. I only point this out if you're thinking of changing the camber once you get to the track. Have a tie-rod rotation scenario played out ahead of time that hopefully you can do with your friendly alignment guy. You'll find that very small rotation of the tie-rods results in significant toe movement, btw.

Sounds like you're in the same boat as I am with regards to the suspension for occasional track use. I'm leaning toward GC coilovers with the Dinan rear bar like Redshift has now . I'll get a chance to see what it's like at VIR this weekend if I can ride with Brian during an instructor's session. I'm leaving the M5 at home (so my wife's V70R will get a workout) as the only mod I have done so far is 9.5" front wheels with 275/35's...need to mainly get my track wheels/tires and brakes sorted first.

stever · 8th September 2004, 20:08

Jeff Blonder who showed me the fast way around Thunderhill in his black M5 put Kmacs on his wifes E36 M3. He had a very careful alignment done at stock camber (positive limit of the Kmacs) and at 3 degrees negative, then scribed marks on the plates (nearly the negative limit) so they could be adjusted at the track. He said toe change was negligible.

the E46 M3 toes out slightly as you go from 1 to 2 1/2 negative - about the amount you need for quicker turn-in.

You certainly need to get an alignment done at street and track camber settings and perhaps decide on a compromise toe setting, but i believe the problem of toe change with camber change is not a serious issue.

Hope to find out for myself soon after deciding which way to go.

CSBM5 · 30th August 2005, 21:13

Reviving this year old thread...

I just installed the GC adjustable camber plates with the stock springs. The GC plates increased the front ride height by about 1/8" or a tad more. I measured the front ride height at 15" center of roundel to fender lip versus 14 3/4 to 14 7/8 stock. The maximum negative camber the plates can provide is around -1.6 to -1.8 degrees as I have them maxed out and that is all I can get.

GC claimed two things on the phone: (1) the plates will not increase the ride height and will actually lower it since they are "very low profile"; and (2) you will be able to get 2.5 to 3.0 degrees negative camber.

Looking at the stock upper spring/bearing mounts, there is no possible way for anything to be any lower profile than the factory mount imo -- they are extremely thin from strut mounting plane to the spring plate (maybe 1/4").

So...I'm not all that pleased with what I was told versus the truth of the installed end result.

At this point I'm considering H&R front springs and Konis all around. I want to try to keep as close to stock ride comfort as possible while maximizing track performance for the very few times per year I hit the track or autocross.

Chuck

Lscman · 30th August 2005, 21:50

Quote:

Originally Posted by CSBM5

Reviving this year old thread...

I just installed the GC adjustable camber plates with the stock springs. The GC plates increased the front ride height by about 1/8" or a tad more. I measured the front ride height at 15" center of roundel to fender lip versus 14 3/4 to 14 7/8 stock. The maximum negative camber the plates can provide is around -1.6 to -1.8 degrees as I have them maxed out and that is all I can get.

GC claimed two things on the phone: (1) the plates will not increase the ride height and will actually lower it since they are "very low profile"; and (2) you will be able to get 2.5 to 3.0 degrees negative camber.

Looking at the stock upper spring/bearing mounts, there is no possible way for anything to be any lower profile than the factory mount imo -- they are extremely thin from strut mounting plane to the spring plate (maybe 1/4").

So...I'm not all that pleased with what I was told versus the truth of the installed end result.

At this point I'm considering H&R front springs and Konis all around. I want to try to keep as close to stock ride comfort as possible while maximizing track performance for the very few times per year I hit the track or autocross.

Chuck

I suspect they did not have specific comparison info and they gave you generic BS. Sad but true.

I would not be upset about ride height increasing 1/8" or so. The other alternatives jack the nose even higher, including Dinan plates and KMAC.

The adjustability of camber on this particular GC product is likely limited by the monsterous 6"+ OEM spring diameter. Turn the steering wheel and look at your spring clearance inside the strut tower. The GC plate can not offset the strut from stock position so far as to cause the spring to scrape the strut tower when you turn the steering wheel.

IMO, GC did their best to design and adjustable strut mount for OEM spring fitment. I am frankly thankful that it's available for the E39 sedan.

If you want more camber adjustability, you need to purchase their strut mount for the slender GC coil-over spring configuration. The Eibach springs are less than 3" diameter & this allows for more strut camber adjustability.

Richard in NC · 31st August 2005, 03:27

The GC plates seemed the best from what I read (and was told over the phone). I agree not understanding how they could advertise what they do and it doesn't work out the same. I would hope they used an M5 to test fit the product. If so, how did they arrive at the numbers they did would be my question to them

Need4Spd · 31st August 2005, 06:11

Based on this report, even though they may not be ideal for track b/c of the limited amount of neg. camber, the GC plates are still the best street setup, as you rarely would want more than 2 degrees neg. on the street, esp. if you do a lot of highway driving, as you'd prematurely wear the inside edges of your tires, and it only adds 1/8" to the ride height. As Rick pointed out, the others add more height. I wish they had a pic on their site though. I'd want to see them before buying. Anyone have pics?

CSBM5 · 31st August 2005, 06:18

Sorry, I screwed up and didn't get pictures of them before the install.

mottati · 31st August 2005, 08:12

that's too bad. Looks like the GC camber plates really provide no more negative camber than dinan fixed plates, so what's the point really? I drive around with -1.6 with no street issues at all. I wouldn't ever mess with them (I.E. Adjust them) unless i could really get some negative camber out of them for those track days.
Mike

03E39M5 · 31st August 2005, 09:49

The little extra "ride height" you get with the plates is NOT going to make a performance difference and should really not be a concern to anyone. However, going from the "stock" camber to a modified camber setting with the plates will give you quite a bit more negative toe, and will chew up your tires way faster than necessary unless the toe is reset after adjusting the camber. You can kill a set of front tires in one day at the track this way (ask me how I know).

Just a warning for those considering the adjustable plates.