[Zl1+911]

HI folks, I am considering upgrading my rear suspension with BMR components for better handling on track and have a few questions. I called BMW but the answers they provided were more generic than I wanted, so getting some input from suspension gurus here. Car is a A10ZL1.

I am looking to change the upper control arm, lower control arm and the toe bar. BMR recommended these 4 parts -

BMR-TCA060H Lower trailing arms, single adjustable, rod ends
BMR-TR007H Toe rods, rear, double adjustable, rod ends
BMR-UTCA062H Upper control arms, single adjustable, rod ends
BMR-UTCA059H Upper trailing arms, single adjustable, rod ends

My questions -

1) For being able to adjust and HOLD rear toe - do I really need adjustable rods? The factory ones are not adjustable and still allow for toe and camber, so I am not sure why I need adjustable
2) Do I need all 4 of these? Which ones are the most impactful on suspension geometry under track conditions? (yes I have the BMR cradle kit already)
3) Which of these specifically get rid of the 2 OEM TTY bolts that are needed? What are the bolts replaced with? BMR provided ones?
4) Any other input?

thanks a lot!!

[Mark R]

I have the same car as you, and pretty much went BMR all the way. I have the cradle lockout, non-adjustable upper control arm, non-adjustable upper and lower trailing arms, toe rods, chassis mid brace and strut tower brace.

The most impactful upgrade is the cradle bushing upgrade, which you have done.

The toe rod deletes the eccentric adjuster, so that bolt does not need to be replaced at alignment time. You bolt the rod in, and adjust by turning the rod in or out, making it longer or shorter. It is supposed to hold alignment longer and more precisely, because of its strength and the elimination of the eccentric adjuster.

The control arms that might eliminate the additional TTY bolts would have to be the double adjustable ones, since they adjust like the toe rod, but you would have to call Frank at BMR for clarification to see if they eliminate the eccentric adjusters. He is the one who is most knowledgeable about Gen 6 Camaros.

I'm super happy with my setup. The car has a very precise and tight feel to it. Left-right transitions are much better - no tail wag anymore, as the rear suspension used to take time to settle. It's pretty much rock solid.

I think you are on the right track.

I added pics of stock VS BMR pieces. The BMR are obviously very stout.

[Zl1+911]

Thank you Mark! Very helpful. So, it seems that non- adjustable arms (outside of the toe rod) are just fine. One more question for you - any tips on how hard the install was? and the time it took you/your shop? thanks

[Mark R]

I had a shop do the bushings and control arms at once, getting the toe rods another year later. If you do all at once it would probably be 5-6 hours of shop time. Not sure, but Frank also has those hours available. (Plus an alignment).

Also, you have to replace all the mounting bolts on this installation.

[Zl1+911]

thanks Mark - you dont happen to have the OEM part numbers that the BMR components replace do you? The shop wants to know to look up the install time. thanks

[Mark R]

Sorry, I don't.