[TheLimitedProject]

Hey guys, looking for some help on an issue that's consistently occuring with my BC Sports BR series coilovers.

As a side note, I've been working closely with the owner of BC North America to try and figure this out, but I wanted to see if the suspension guys on here had any other input.

So here's the problem:
When there's a sharp dip in the road (the extreme example being a pot hole), my rear c/o's make a very loud, sharp bang/clunk. It sounds like metal on metal.
When there's a bump in the road (the extreme being a speed bump, for example), the suspension doesn't make a sound.

So, I'm only hearing the bang when there's
Load (normal driving)
to
Less load/no load (in the dip)
to
Full load again (coming out of the dip).

Here's what I've done to try and fix the problem (none have worked):
1 - Tighten down the top hats
2 - Tighten the top locking nut
3 - Adjust the spring preload to have more tension (and less tension).
4 - Swapped out the pillow-ball top mounts for rubber mounts.

The only thing I haven't done is change my ride height. But I don't want to do that and shouldn't have to I don't think. I've seen some slammed cars before and haven't heard people complaining about this.

So, any other ideas? I'm at the end of my string with this...

At this point, my guess is that the banging is coming from the strut part of the assembly. But, I'm no suspension expert, so I really have no idea.

Thanks a LOT for any help!

ps. There are many STI owners using these coilovers, and I'm apparently the only one so far with this issue. An EVO owner had the same issue, but the rubber mounts solved his problems.

[BoostJunkie]

It sounds to me like something internal but it's hard to diagnose without hearing it myself. If you have tried all of that and it's still making the noise, I would send them back for a replacement if you can. There is obviously more noise associated with coilovers and solid top mounts, but it sounds to me like this is louder than normal.

[RainMaker]

Is there enough droop travel? You could be running into the end of the shock travel as the spring extends the shock. Then it would clunk since its a hard "end".

[RainMaker]

Originally Posted by BoostJunkie

There is obviously more noise associated with coilovers and solid top mounts, but it sounds to me like this is louder than normal.

For.... "the benefit of the populace", I think it would help if we could quantify how much and what type of noises are common in the back with coilovers and metal-metal tophats. What do you think coilovers in the rear should sound like (normally)?

[SilverSuby]

What is your ride height at? I have the same coilovers.

[!4KORNRZ!]

Do you have bumpstops on the assembly?

What is your height measurement?

[TheLimitedProject]

I started this thread and then went away for a few days so I haven't been able to reply.

Anyway.....

Originally Posted by RainMaker

Is there enough droop travel? You could be running into the end of the shock travel as the spring extends the shock. Then it would clunk since its a hard "end".

The problem isn't in the extension, it's in the contraction or compressing of the c/o. The bang happens when I hit a "space" in the road, the load on the suspension is much less, then it bangs when the assembly compresses again when it hits the road again. It all happens extremely quickly.

Originally Posted by SilverSuby

What is your ride height at? I have the same coilovers.

In mm or inches, I have no idea. It's definitely low.
Here's some pictures:

[JKonquer]

do you have picture of the front?

[TheLimitedProject]

By the way, after speaking with the owner of BC, ride height has no bearing on how the shock travels. So, lowering the car a lot won't make them bang...