Camber plate options

[Kubricks]

Hi all,

My 130i has recently upgraded to some R-compound (A050-M) for occasional track use, discovered immediately that the current camber is not sufficient, what are my options?

Situation;
1) Currently running 2.2 degree with camber pin mod, M3 wishbone, Dinan camber plate (fixed camber).
2) N/H/V not important, so solid mount adjustable camber plate can be considered.
3) Stack height of the camber plate must be minimal. I am using Birds B1 suspension, non-height adjustable. The spring rate and damping is very well judged so I have no intention to change it. Since it is non-height-adjustable I need the camber plate with minimal stack height increase otherwise it is going to throw the F/R balance off.

Any comments and experience on different camber plates here? I was thinking of drilling the damper mounting point for a larger camber too... not sure this is safe tho', anyone done it before?

Thanks!

[John_01]

Does the birds suspension use OE type struts and spring hats? If so, the ground control street plates are quite a solid option and are available to suit stock size springs. They are good for street and track dual duty, although they transmit a lot more vibration than the stock setup.

What the size are your A050 tyres? Do you know the offset of the wheels?

[HP Autosport]

Running R-Comps on a B1 setup is VERY bold of you. I would want a much stiffer setup to effectively use the R-comps. Even dialing in more camber won't help with efficiently using those tires. Negative 2.2 degrees isn't THAT bad. I would either suggest going to a high performance street tire and adding the camber plates for more camber or think about getting a different suspension setup all-together. I am not saying B1s are bad, it's just like using slicks on Koni yellows, not the BEST of ideas to maximize performance.

-Mike

[Kubricks]

Originally Posted by John_01

Does the birds suspension use OE type struts and spring hats? If so, the ground control street plates are quite a solid option and are available to suit stock size springs. They are good for street and track dual duty, although they transmit a lot more vibration than the stock setup.

What the size are your A050 tyres? Do you know the offset of the wheels?

Thanks! I will look into it.
Tyre size are 225/40/18 front and rear, on 18" 8.5" ET44 front and 18" 8.5" ET39 rear Prodrive GC-014i. No rubbing so far.

Originally Posted by HP Autosport

Running R-Comps on a B1 setup is VERY bold of you. I would want a much stiffer setup to effectively use the R-comps. Even dialing in more camber won't help with efficiently using those tires. Negative 2.2 degrees isn't THAT bad. I would either suggest going to a high performance street tire and adding the camber plates for more camber or think about getting a different suspension setup all-together. I am not saying B1s are bad, it's just like using slicks on Koni yellows, not the BEST of ideas to maximize performance.
-Mike

I agree with what you said. I fit this tyre to test the limit of this suspension set up. (previously running PSS/Z1*/RE11/RS3 and alike)

Ideally, as you have mentioned, I should be running a much stiffer set up. Nevertheless, the B1 is holding up alright for aggressive street driving but track work I will have to wait till Dec. Temperature indicates I need more camber on these tyre, I guess another 0.5 degree will do. I think it all depends on how much effort I have to put in for that extra 0.5 degree, if it turns out not to be readily available or too costly or the stiffness from B1 just won't cut it I will switch back to high performance street tyre.

Thanks all!

[Pyrat 2]

Why do you think that you need more camber? The picture you show has virtually no outer edge wear.

[Kubricks]

Originally Posted by HeelToe

Why do you think that you need more camber? The picture you show has virtually no outer edge wear.

The photo was taken before I had a hard run with it.
The temp is a good bit hotter on the outside edge after I did the run.

[Pyrat 2]

Higher temps on the outer edge is normal for sure. Have you tried chalking the edges to determine how much roll onto the sidewall is occurring and whether it is balanced front to back?

[John_01]

I don't know about the B1 suspension, but have you considered firmer sway bars to keep the body roll under control? The body roll will contribute to the higher temperature and wear on the shoulder of the front tire.

[Ginger_Extract]

Originally Posted by John_01

I don't know about the B1 suspension, but have you considered firmer sway bars to keep the body roll under control? The body roll will contribute to the higher temperature and wear on the shoulder of the front tire.

I agree with this. If you think that your spring/damper solution is where it should be, try a more aggressive front sway bar, that should help mitigate deflection, and/or excessive camber change under loading.
To answer your question, however, Vorshlag makes some great fanfare over their camber plates not changing overall stack height.

[Kubricks]

Originally Posted by John_01

I don't know about the B1 suspension, but have you considered firmer sway bars to keep the body roll under control? The body roll will contribute to the higher temperature and wear on the shoulder of the front tire.

Oh I should have be more specific, I have the following mods apart from the one listed;
- E90 M3 front anti-roll bar (26.5mm) with M bushing
- Ultra racing rear anti-roll bar (16mm solid) with polyurethane bushing, I also had a 13mm rear m-sport and 22mm E90 M3 rear anti-roll bar for testing/tuning, I found the 16mm bar gives the best balance and rear traction on sticky street tyre. I might go back to the 22mm rear bar on these R-comp, don't know.
- Quaife limited slip diff.
- M3 rear subframe bushing

[Kubricks]

Originally Posted by HeelToe

Higher temps on the outer edge is normal for sure. Have you tried chalking the edges to determine how much roll onto the sidewall is occurring and whether it is balanced front to back?

Will do.
By just eye balling the front experienced more outer edge wear than rear.
currently running front 2.2 degree rear 1.6 degree.

[John_01]

Interesting to hear your feedback about the rear sway selection.

[Kgolf31]

Originally Posted by HeelToe

Higher temps on the outer edge is normal for sure. Have you tried chalking the edges to determine how much roll onto the sidewall is occurring and whether it is balanced front to back?

I wouldn't call high temps on the outside tire normal.

Typically you want temps to be hottest on the inside and reduce as you go to the outside of the tire.

Originally Posted by HP Autosport

Running R-Comps on a B1 setup is VERY bold of you. I would want a much stiffer setup to effectively use the R-comps. Even dialing in more camber won't help with efficiently using those tires. Negative 2.2 degrees isn't THAT bad. I would either suggest going to a high performance street tire and adding the camber plates for more camber or think about getting a different suspension setup all-together. I am not saying B1s are bad, it's just like using slicks on Koni yellows, not the BEST of ideas to maximize performance.

-Mike

Negative 2.2 isn't ideal either.

SCCA Stock classes seem to make do with R-Comps. It isn't ideal, but it is what the class dictates.

Originally Posted by John_01

Interesting to hear your feedback about the rear sway selection.

Why would you even consider a rear sway? Do you really want to end up with an upset chassis?

[John_01]

Originally Posted by Kgolf31

Why would you even consider a rear sway? Do you really want to end up with an upset chassis?

What makes you think its upset? The OP claims he's tried several rear sways and found what he likes. If using a LSD, its perfectly reasonable to balance the sways between front and rear. He is not the only one who tried an M3 rear sway on the 1 series and later removed it.

[Pyrat 2]

Originally Posted by Kgolf31

I wouldn't call high temps on the outside tire normal.

Typically you want temps to be hottest on the inside and reduce as you go to the outside of the tire.

Negative 2.2 isn't ideal either.

SCCA Stock classes seem to make do with R-Comps. It isn't ideal, but it is what the class dictates.

Why would you even consider a rear sway? Do you really want to end up with an upset chassis?

Agree to disagree on the temps. Some variation is normal and the outside edge in many cases is warmer as it works harder in the corners. If it didn't then one wouldn't be adding camber in the first place.

[Kgolf31]

Originally Posted by John_01

What makes you think its upset? The OP claims he's tried several rear sways and found what he likes. If using a LSD, its perfectly reasonable to balance the sways between front and rear. He is not the only one who tried an M3 rear sway on the 1 series and later removed it.

Because BMWs don't need rear sways on a proper set-up car.

I don't see if being any benefit to adding a rear swaybar, and here is why:

1. Sways bars help reduce weight transfer on the given axle that is is currently on (for example front axle) by transferring it to the rear. This is why on BMWs, you actually reduce understeer instead of the common lack of knowledge that you increase understeer. The weight transfer is relocated to the back axle, thus instead of having that grip on the front left (for a left hand turn) it is transferred into the left rear wheel.

2. If you add a rear swaybar, you eliminate this weight transfer. Now you increase understeer, and because you don't have that effective weight transfer going to the rear wheels...you eliminate all potential rear grip because you stiffened up the rear too much. Grip is dependent on weight transfer.



I run a stock rear bar (and have actually removed it to experiment) and run a 30mm front bar on my Z4M and would hate it to run anything bigger than stock in the rear. It makes the rear end unpredictable, doesn't want to rotate and cannot put power down.


Not everything done should be replicated on front/rear axles.

TC Kline himself runs stock or no rear bar on his race prep'ed E36s and other chassis cars. I trust his recommendations

Originally Posted by HeelToe

Agree to disagree on the temps. Some variation is normal and the outside edge in many cases is warmer as it works harder in the corners. If it didn't then one wouldn't be adding camber in the first place.

I'm talking about ideal tire temps, not what OP is noticing.

[fboutlaw]

This feels like a good place to post. I can't see anything weird in your first post, but as you said this was pre-running the tire. Also, with that setup, you're likely not racing, but just tracking the car, right? You should be good with the current setup, but your options for camber plates:

Vorshlag camber plates
Ground control camber plates

Both are adjustable. I run a similar setup, (m3 front sway, and bits, + yokos), but with -3.5 deg front, -1.6 deg rear camber. Here's what my wear looks like after a run:

[John_01]

Originally Posted by Kgolf31

I don't see if being any benefit to adding a rear swaybar, and here is why:

1. Sways bars help reduce weight transfer on the given axle that is is currently on (for example front axle) by transferring it to the rear. This is why on BMWs, you actually reduce understeer instead of the common lack of knowledge that you increase understeer. The weight transfer is relocated to the back axle, thus instead of having that grip on the front left (for a left hand turn) it is transferred into the left rear wheel.

2. If you add a rear swaybar, you eliminate this weight transfer. Now you increase understeer, and because you don't have that effective weight transfer going to the rear wheels...you eliminate all potential rear grip because you stiffened up the rear too much. Grip is dependent on weight transfer.

In my understanding the sway bar increases the weight transfer for the axle that its on. The additional weight transfer comes though the sway bar bushings to the body of the car.

Adding a rear swaybar increases the weight transfer for the rear axle of the car and reduces the weight transfer on the front axle. More weight transfer on the rear axle means less grip at the rear of the car, and it reduces understeer. Because of the rear swaybar, the front tyres share a more even load and can provide more overall grip. In particular the inside front wheel will produce more grip in braking and turning to effectively hook the front of the car into the corner.

[Kubricks]

Originally Posted by Kgolf31

skip

This is a street setup car for occasion tracking not a dedicated track toy nor race car, so there are a lot of compromise I made here. Ideally I will be using a very stiff setup with much higher spring rate and minimal or none anti-roll bar for maximum grip, but that will also create a car that would be very difficult to live with on day to day basis.

Anyhow, I do have reasons on my set up and calculation to back it up, but do not feel like discussing/explaining/debating it here as this is not the purpose of my thread. Hope you can understand.

[Kubricks]

Originally Posted by fboutlaw

This feels like a good place to post. I can't see anything weird in your first post, but as you said this was pre-running the tire. Also, with that setup, you're likely not racing, but just tracking the car, right? You should be good with the current setup, but your options for camber plates:

Vorshlag camber plates
Ground control camber plates

Both are adjustable. I run a similar setup, (m3 front sway, and bits, + yokos), but with -3.5 deg front, -1.6 deg rear camber. Here's what my wear looks like after a run:

Yes.
Now the tyre wear on your photo is more like it lol, not sure whether I can hit -3.5 degree on OEM spring size tho'.

I will check on the two plates.

Thanks all!

[Kgolf31]

Originally Posted by John_01

In my understanding the sway bar increases the weight transfer for the axle that its on. The additional weight transfer comes though the sway bar bushings to the body of the car.

Adding a rear swaybar increases the weight transfer for the rear axle of the car and reduces the weight transfer on the front axle. More weight transfer on the rear axle means less grip at the rear of the car, and it reduces understeer. Because of the rear swaybar, the front tyres share a more even load and can provide more overall grip. In particular the inside front wheel will produce more grip in braking and turning to effectively hook the front of the car into the corner.

Typically that is what a sway bar does...but on a BMW it is lop-sided thinking.

Adding a rear bar, in my experiences increases push.

Originally Posted by Kubricks

This is a street setup car for occasion tracking not a dedicated track toy nor race car, so there are a lot of compromise I made here. Ideally I will be using a very stiff setup with much higher spring rate and minimal or none anti-roll bar for maximum grip, but that will also create a car that would be very difficult to live with on day to day basis.

Anyhow, I do have reasons on my set up and calculation to back it up, but do not feel like discussing/explaining/debating it here as this is not the purpose of my thread. Hope you can understand.

I don't see why compromise needs to be made for a daily driven car.

Adding spring rate doesn't correlate to grip. E36 race cars made by TCK run soft spring rates (typically like #500 to #600, maybe even less).

This article should help explain some:

http://www.bimmer-mag.com/issues/101...ndling-machine

YMMV, but it has been proven.