s13/s14 subframe bushing for non-metal autox classes

[hai1206vn]

Just to post what I found a while agohttp://mmr-direct.com/catalog1/S13/index.htm

About UHMW: http://en.wikipedia.org/wiki/UHMW

These are solid plastic bushings, almost as hard as aluminum, and help you fix that clunk in the rear and wheel hop, without getting bumped out of a racing class that prohibits metal bushings. They are made for s13 but will fit s14 as well.

As you see, MMR also makes solid UHMW engine + transmission mounts for pretty cheap.

I'm using their subframe bushings, Energy suspension z32 diff bushings, Nismo transmission mount and Windo-Weld filled motor mounts. All the slack that remains is probably from the motor/transmission mounts. No complaint about the MMR stuff, except that the rear end got a bit noisy for a street car (but it could also be my ring&pinion not meshing properly)

Btw I'd choose a plastic-metal contact over metal-metal contact (as with any aluminum part touching steel) because of galvanic corrosion possibility of the latter.
Modified by hai1206vn at 1:22 AM 12/10/2008

[le_ryan]

bump for more info, do you still hear any clunking back there, any other issues ?

[hai1206vn]

The clunking is definitely from my pinion & ring gear backlash. I think that makes the rear end noisy during normal cruising/coasting too.

I'm pulling it out next week to get the side shims adjusted. There'll be an update soon

Right now it's the exhaust that is louder than everything else. I have BRM 2.5" and urethane hangers, with solid subframe bushings, so the drone at 60+ mph is a bit annoying.

[hai1206vn]

So i got the diff re-shimmed to spec and installed it. It got quieter but I can still hear a bit of clunking if I let off the clutch fast (not dumping, just relatively fast) at wrong RPMs.

Yesterday I put in the rubber inserts sandwiched between the subframe bushings and the body (zerothread/302595, not made anymore) hoping to kill some more noise, but those only improved a little bit.

Well, having tried everything, it should be safe to say that the clunking will be there for any kind of solid bushing. On the good side, the little noise there is a good reminder of drivetrain shock whenever I don't shift precisely.

[n00b240]

For me, I no longer have any clunking of any kind coming from the subframe. But the differential clunks maybe 25% of the times I let up off the clutch. However, when Im driving faster/ autocrossing, quickly shifting I dont hear any clunk from the differential.

Ive got the solid aluminum bushings. I agree that for the solid diff bushing, there will always be some type of clunk for metal on metal.

I dont mind the subframe noise at all. Ive gotten used to it, and the car handles much much better, so ive got no beef. But anyone who rides with me, or if Im talking on the earpiece phone, its their number one complaint. Its too loud.

[hai1206vn]

Yea I also got used to the final drive noise. My exhaust that's resting on the subframe and curious interior rattles are the things that bother me right now.

I'll be taking it easy on the drivetrain for some hundred miles before trying shifting faster, popping the clutch, etc.

As long as the subframe stays solid, I can accept the tradeoffs

[n00b240]

After I installed the bushings, EVERYTHING began to rattle. I found out that in the window regulator, some of the nuts werent completely tight (I swapped the window regulator myself), and the door handle screws were a lil loose. After tightening those, I heard no more rattles save for the pennies and coins I have in that center holding bay.

[White Comet]

hmm interesting to see these. i went with ES pineapple bushings, still non metal and they cost $65

[hai1206vn]

it took me a long time to figure out why Japanese call those rings pineapples. Apparently they don't have whole pineapples in grocery stores.