[bogga]

How much, if any, do the factory rubber bump stops compress under full compression with total running weight?

[Gwagensteve]

At least 50%

[bogga]

Thanks Steve.
Bit more than i assumed.

[JrZook]

Gwagensteve wrote:

At least 50%

The standard ones? I would have said 50% absolute max under normal wheeling/driving conditions ie no high speed jumping etc. They are pretty darn hard.

[Gwagensteve]

My rear end is currently sitting on the bumpstops. (Springs removed) they have compressed 50% of their free height- to the base of the angled section.

[bogga]

Gwagensteve wrote:

My rear end is currently sitting on the bumpstops. (Springs removed) they have compressed 50% of their free height- to the base of the angled section.

So based on that they would compress more than 50% in a situation where all the weight of the car was on one corner (on a incline/decent 4wding)?

[Bruce]

Are you trying to get more compression out of them or less?
I only ask as I can make them harder or softer if needed.

[bogga]

Using stock mounts. Was just curious as to the compression for when I set up the suspension and body.

I do tend to overthink things but better than putting no thought into a build.

[Gwagensteve]

Set it up metal to metal.

[MrRocky]

When they regularly get compressed to that point they split, been through a couple sets now. Interestingly the later model wt's run a rounder type bumpstop thats seemed to last well

[sideways]

I crushed a Sierra front bumpstop in my 20T press today. It's from an early 1l so it's probably harder than most.

Uncompressed about 45mm tall.

Crushed just about as hard as the press will go, 20mm.

It compressed easily until about 25mm when it got quite hard. I've crushed quite a few bumpstops in the press now and it's been the same with all the block/non-progressive bumpstops, a million pumps with no effort and then within a few pumps it's basically solid. They always go to around half their height. Progressive bumpstops on the other hand really seem to do what they say on the box, progressively get harder. I've never crushed a progressive one to the maximum capacity of the press (they look like they're going to pop and they're to valuable to me) but they don't seem to have an obvious hard stop like block bumpstops do.

I was using a flat plate so the round diff housing will punch into it a bit easier, I reckon 20mm is a safe height to base shock selection off.

Might try a rear one later.