Rear Lower Spring Perch for Race Springs

[fe1rx]

The OE rear springs have open ends and require rubber spring perch isolators that support their coil profile.



Because of the way the spring articulates when the camber arm moves, the lower spring perch isolator tends to wear at the end of the spring.



Race springs are flattened and ground and present a generally flat support surface at both ends. As such the OE spring perch isolators don’t work. I am installing an Ohlins Road and Track suspension in my 135i. The kit does not provide any rubber isolators for the bottom end of the rear spring. Harold at HP has advised me to simply install the spring metal to metal with the camber arm, but given its profile, this really doesn’t sit well with me.



I have been unable to find a suitable off-the-shelf isolator pad that has the correct profile to match the camber arm. What I did find was Energy Suspension p/n 9.6121G, which is the right size but has a square profile. To make these work, I machined them to the correct profile.



They now sit flat on the camber arm.



Here it is with a race spring sitting in place.

[arcticcat522]

that's lookin good man, u didn't machine an extra set for a fellow Canadian by chance?



adam

[fe1rx]

Originally Posted by arcticcat522

that's lookin good man, u didn't machine an extra set for a fellow Canadian by chance?



adam

No, but tell you what, send me a couple with return postage and i will machine them for you. Holding them for machining is a bit of a pain, but I made a fixture. If they were rigid, turning them on a lathe would be simple. I did them on a CNC mill with a ball end mill doing surfacing passes (in case you are interested).

Anyway, if you really want them, send me a PM.

[ashmostro]

I've got noise coming from my coil setup and I think it's because of the bare metal to metal contact. Still willing to grind 2 down if I supply them?

[Hierlevelz]

Originally Posted by fe1rx

No, but tell you what, send me a couple with return postage and i will machine them for you. Holding them for machining is a bit of a pain, but I made a fixture. If they were rigid, turning them on a lathe would be simple. I did them on a CNC mill with a ball end mill doing surfacing passes (in case you are interested).

Anyway, if you really want them, send me a PM.

Judging by the photos you put a chamfer on the inner diameter of the bushings so they would sit flush on control arm?

[fe1rx]

For those that may need these parts and have the technology to do the mod, here is the required geometry.

[mike082802]

are these necessary for coilovers? i bought swift thrust sheets. also i wonder if you could heat them up and make them fit?

[uberschnell]

I ran my swift springs with thrust sheets. Seemed to work well.

[1-r6]

Hey i believe u live in ontario right just wondering if u can make one for me?

[fe1rx]

Originally Posted by 1-r6

Hey i believe u live in ontario right just wondering if u can make one for me?

Sure, but you will probably need two!

Send me a PM if you are interested.

[Jeff9962]

That's great information as usual and I'm swapping springs this weekend so I'll see what mine look like. A good friend is a machinist so I'll likely have him make up a set for me.

[iminhell1]

No Delrin shear plates?
I'm disappointed.