Conservative Factory Alignment Specs on a Lowered M3

[Malek@MRF]

This is the result of 7000 miles of driving on the rear wheels of an E92 M3 when aligned with factory alignment settings on a vehicle lowered 1.3 inches in the rear on KW V3 coil over suspension.

The factory alignment specifications work great when the car is at stock height or close to it. When we start the lower the cars and change the wheel offset and widths, things start to become different.

For example, BMW states that the car should be aligned with 0*14' of total toe in for the rear suspension. This is what BMW states as the maximum recommended TOE-IN. As you can see in the pictures, it is simply not enough. BMW's specified range for camber on the rear end is a good range. Keeping the numbers within that range is good measure. It is really up to the drivers style and use of the car how conservative/aggressive he/she intents to use the car.

Interestingly enough, this specific M3 driver complained about the car feeling "loose" and that the back end did not provide enough stability and felt like it wanted to spin out.

Here are a couple pictures to show you guys.

Moral of the story, the BMW specified Toe values do not apply effectively to moderately low E9x M3's.





--Malek

[SaNGRia]

Hey, it is little bit an old topic. I would like to ask you this, i had lowered my car with KW Sleeve and used different settings to see how i feel, i then found the right setting that i like and drove about 800 miles with the old tires and start seeing the same results it shown above pics. since the tires was old it didn't bother me. SO i got the new set tires and dropped the car to the best mechanic around the town and they did a fantastic job. car goes straight forward on any speed. (they use some weight to simulate driver weight as well)

The question is i feel the same loose feeling your customer complained before. If i drive straight forward everything is good If i do sudden steering wheel movements while driving about 80 - 90 mhp, feels like the springs are not too tight.

When i lowered the car, i did not measure the height. I just turned the adjustable knobs number of times (lets say i turned 6 times on the front, 4 times on the rear end).

I am wondering what can cause this problem?

After making some researches the critical point they say is front should be tighter than rear springs otherwise it will bounce.

Well more you turn the knob, it gets more tighter on the springs right?

I mean the car feels loose a bit side to side wobble. wondering even tho i turned them same number of times, but one side is little lower or higher than other somewhat?

I need experienced members opinion also please!

[Solo_M_Tech]

If factory specs create excessive toe wear, then what specification do you recommend? Too much toe in will create cupping/scrubbing, whereas not enough creates the wear pictured in the original post.

[spazzyfry123]

Originally Posted by ham_sammich

If factory specs create excessive toe wear, then what specification do you recommend? Too much toe in will create cupping/scrubbing, whereas not enough creates the wear pictured in the original post.

[dsenechal]

Would also like to know what recommended specs would look like?

[su_root]

Lowering the car always results in suspension values(camber, toe etc) outside of factory spec leading to tire wear outside of factory expectations.

in the pics we can't see the entire tire circumference but that looks like excessive camber.

personally, i've struggled with severe inside front tire wear after ohlins r&t with ground control camber plates. the ohlins were installed by a local tech(regrettably) and i honestly don't know how to go about adjusting camber. that said all adjustable settings(preload, spring perch, etc) are dialed in to ohlins install manual settings which effectively lowers the vehicle 20mm from factory spec.

i feel i need a suspension expert but i also plan to contact the GC guys and get their opinion on how to best use their kit when combined with ohlins rt.

MRF, if you can help educate me on the questions i should be asking the alignment shop i end up taking the vehicle to id greatly appreciate it

[Solo_M_Tech]

Originally Posted by su_root

Lowering the car always results in suspension values(camber, toe etc) outside of factory spec leading to tire wear outside of factory expectations.

in the pics we can't see the entire tire circumference but that looks like excessive camber.

personally, i've struggled with severe inside front tire wear after ohlins r&t with ground control camber plates. the ohlins were installed by a local tech(regrettably) and i honestly don't know how to go about adjusting camber. that said all adjustable settings(preload, spring perch, etc) are dialed in to ohlins install manual settings which effectively lowers the vehicle 20mm from factory spec.

i feel i need a suspension expert but i also plan to contact the GC guys and get their opinion on how to best use their kit when combined with ohlins rt.

MRF, if you can help educate me on the questions i should be asking the alignment shop i end up taking the vehicle to id greatly appreciate it

What's pictured here is not camber wear. That is excessive toe out wear condition. Which can be fixed with a proper alignment using aftermarket toe arms ( if required). If you have the same issue on the front, the alignment is to blame ( specifically toe adjustment isn't correct).