Anyone tell me what these are and where they go?

[Wellardmac]

When I bought my E90 M3 I was given a couple of threaded pins by the previous owner. He said they were "pinion pins" and that he took them out to help handling when he autocrossed.

I would like to put the pins back in their rightful place, but a search on "pinion pins" didn't turn up anything useful to tell me where they go and how to put them back. I would really appreciate guidance from anyone that can point me in the right direction.

[Richbot]

Those are the alignment pins for the upper strut mounts. They locate the strut mount in place from the factory to maintain the factory alignment settings. They are pulled to allow the strut mount to slide in the slotted upper mount to get additional negative camber. See the DIY section for details.

[Wellardmac]

Awesome, thanks - no wonder I couldn't find anything on them when I didn't have the correct name. Are they easy to reinstall?

[Groundpilot]

They are very easy to reinstall, but why would you want to do it?

[Porschefile]

Reinstalling those will only make the car handle worse.

[Wellardmac]

Okay - good to know. Does having them out have any impact on tire wear?

My front tires have worn on the inside edge (a lot faster then the rest of the tire), so I'm pointing the finger at a bad alignment and left wondering if the pins being out contributed.

[CanAutM3]

Originally Posted by Wellardmac

Okay - good to know. Does having them out have any impact on tire wear?

My front tires have worn on the inside edge (a lot faster then the rest of the tire), so I'm pointing the finger at a bad alignment and left wondering if the pins being out contributed.

Very likely alignment is off. Usually toe will have much more impact on tire wear compared to camber. Pulling the pins allows you to dial in more camber, but in my opinion not sufficiently to significantlty impact tire wear. So I suspect your toe settings are off.

By the way, you can always re-adjust the camber settings back to stock without having to re-install the pins.

[Wellardmac]

Originally Posted by CanAutM3

Very likely alignment is off. Usually toe will have much more impact on tire wear compared to camber. Pulling the pins allows you to dial in more camber, but in my opinion not sufficiently to significantlty impact tire wear. So I suspect your toe settings are off.

By the way, you can always re-adjust the camber settings back to stock without having to re-install the pins.

Excellent! That's good to know and helps set my mind at ease.

Thanks for the guidance.