[The Nightman]

Does anyone have any feedback on M3 rear guide rods? Based on the findings from this thread, they seem to be a worthwhile upgrade and also easy to install, but I haven't been able to find any detailed reviews.



My other suspension modifications:
- 235/45R17 Pirelli Pzero AS+
- Sport springs w/ Bilstein B4
- 28mm front sway bar
- front M3 tension struts
- rear poly sway bar bushings
- rear poly subframe inserts
- Monroe rear upper shock mounts
- front + rear M3 subframe bracing

[gjm120]

I think they are worthwhile and a pretty easy install. The back end of my car is certainly more controlled and more precise feeling, BUT, I did the guide rods at the same time as Whiteline RSFB inserts and firmed the rebound on my Koni Yellows. So how much improvement came from what is hard to say.

I don't know how much is due to guide rods, but, according to the post you referenced, M guide rods + toe control arms have the effect of lowering rear spring rate by 72 lb/in. My guess most of that reduction is due to the toe arm as that replaces 2 bushings.

[Angel67]

Hey guys.

We have manufactured rear toe arms for the e82 and e9x non-M. The design principle is a curved arm, but with dimensions better suited to the non-M suspension.

These are made of billet 6061-T6 aluminum and have been precision CNC machined to accept either balljoints or bushings (which can be either stock bushings or much stiffer Group N bushings, or even polyurethane bushings like those from Powerflex and other suppliers), or any combination of balljoints and bushings depending on individual preferences. They can be anodized in any colour. They can also be made either in the standard length (412 mm) or +3 mm for extra toe.

Because you can select balljoints or bushings, or any combination, you can tweak your effective spring rates in increments (measured in lb/in). So, for example, on effective spring rates:

- 2 balljoints: 0
- 1 balljoint and 1 regular bushing: 15
- 2 regular bushings: 30
- 1 balljoint and 1 Group N: 56
- 1 regular bushing and 1 Group N: 71
- 2 Group N: 112

Assuming the contribution of a full set of stock bushings is an equivalent of 109 lb/in, then that can be fully compensated with a set of MRP toe arms with 2 Group N bushings, and the other 4 arms can be only balljoints...

Just trying to gauge interest at this point so please reply if you might be interested in this product...

a

Stay tuned!

[nate93]

I've bought a pair of M3 rear guide rods to install on my 335i. The torque specs say to torque them down to 100 NM for bodyside and 100 NM + 90 degree to wheel under load. It says to also replace these nuts and bolts. Do we have to replace them? Is it necessary? They aren't aluminum bolts right?

[Tambohamilton]

That '+90deg' is the giveaway; the bolt will stretch when torqued that much, so it should be replaced NOT reused.

[Angel67]

+1

[WatchWolf34]

What are you defining as "worthwhile"?

Seems to me that the M3 guide rods will soften the effective spring rate based on that thread you shared. Are you looking to reduce oversteer?

[mweisdorfer]

So, when you guys say M3 rear guide rods, are you saying the rear tow arms on the very bottom of the rear subframe?

I thought the M3 version was too short, so 335i owners can't use them?

[feuer]

Originally Posted by mweisdorfer

So, when you guys say M3 rear guide rods, are you saying the rear tow arms on the very bottom of the rear subframe?

I thought the M3 version was too short, so 335i owners can't use them?

You are talking about the toe link, M3 378mm vs non-M 412mm, the rest are all same length.

[mweisdorfer]

Originally Posted by feuer

You are talking about the toe link, M3 378mm vs non-M 412mm, the rest are all same length.

Right. So, you can't use the M3 toe link. It's too short.

[mweisdorfer]

Originally Posted by Angel67

Hey guys.

We have manufactured rear toe arms for the e82 and e9x non-M. The design principle is a curved arm, but with dimensions better suited to the non-M suspension.

These are made of billet 6061-T6 aluminum and have been precision CNC machined to accept either balljoints or bushings (which can be either stock bushings or much stiffer Group N bushings, or even polyurethane bushings like those from Powerflex and other suppliers), or any combination of balljoints and bushings depending on individual preferences. They can be anodized in any colour. They can also be made either in the standard length (412 mm) or +3 mm for extra toe.

Because you can select balljoints or bushings, or any combination, you can tweak your effective spring rates in increments (measured in lb/in). So, for example, on effective spring rates:

- 2 balljoints: 0
- 1 balljoint and 1 regular bushing: 15
- 2 regular bushings: 30
- 1 balljoint and 1 Group N: 56
- 1 regular bushing and 1 Group N: 71
- 2 Group N: 112

Assuming the contribution of a full set of stock bushings is an equivalent of 109 lb/in, then that can be fully compensated with a set of MRP toe arms with 2 Group N bushings, and the other 4 arms can be only balljoints...

Just trying to gauge interest at this point so please reply if you might be interested in this product...

a

Stay tuned!

Where did you get these?

[Tambohamilton]

Originally Posted by mweisdorfer

Where did you get these?

Originally Posted by Angel67

Hey guys.

We have manufactured rear toe arms for the e82 and e9x non-M.

They got them from an aluminium supplier.

[Angel67]

Yup, aluminium supplier, then CNC machining.

a

[nate93]

The red circled bushing on my upgraded M3 guide rod has some motion/play while my stock 335i guide arm has no motion. Is that normal? I was wondering if the red circled bushing is shot?

[Tambohamilton]

That one is a ball joint, unless I'm mistaken. It should move relatively freely (unlike a rubber bushing), but shouldn't have any radial play at all.

[nate93]

Originally Posted by Tambohamilton

That one is a ball joint, unless I'm mistaken. It should move relatively freely (unlike a rubber bushing), but shouldn't have any radial play at all.

So it is normal that there is some play in that ball joint? I can move it as drawn in the picture below. is it what you meant by radial play? I am a bit relieved.

[Tambohamilton]

If you move one side of the joint down and the other goes up, that's fine; it should swivel.

If you can move it in the directions you showed, but keeping the joint perpendicular to the arm, that would be bad.

You should be able to move the joint by hand, probably, but it shouldn't be loose.

[Angel67]

It's normal.

a

[streetpro]

I have changed all those M3 parts bit by bit and I can state that they (these rear M3 rods) do improve maybe like 10% (and we are talking about vehicle with 160k miles)... much greater impact made change of subframe bushings (again M3)... but to get rid of "rear WOT steer" effect I had to put on the diff brace...
new rear shocks, rear M3 roll bar, all M3 bits, rigid toe arms and it was still not planted...
diff brace made it stable, don't ask me why cause it doesn't make much sense to me...

[Angel67]

What engine/tranny mounts do you have?

a

[Tambohamilton]

Originally Posted by streetpro

don't ask me why cause it doesn't make much sense to me...

Glad you acknowledged this bit. I've thought the same, every time somebody has said it. I wonder if someone can explain what's going on...

[feuer]

Originally Posted by streetpro

diff brace made it stable, don't ask me why cause it doesn't make much sense to me...

Originally Posted by Tambohamilton

Glad you acknowledged this bit. I've thought the same, every time somebody has said it. I wonder if someone can explain what's going on...

It negates the ill effect of an axle twist that if not tamed it will start twisting the whole vehicle. Google torque and twist launch images if you want to see extreme cases.