Lowering Question

[LCB1]

Got the stance that I wanted, lowered it 2" rear and 2.5 front. The question I have is that there is only about a 1/2" of travel between the bump stop and the uppper control arm. New upper and lower control arms, 1" lowering springs with an additional 1 coil cut off. Anyone else have this issue and what is the solution.

Thanks

Larry

 

[Silverback]

Honestly, I haven't looked to see where on the control arms the bump stops are mounted, but it may not be a problem with stiff enough springs. If the bump stop is half way between the pivot bolts and the ball joint you'll have 2x as much travel at the wheel than you will at the bump stop. The closer it gets to the pivot the more travel you have.

In a lot of cases the bump stop is also a bigger piece that has some give, typically tapered also, so it becomes part of the suspension tuning. When it contacts the relatively thin tip starts compressing easily and as it compresses more it gets harder, effectively giving you a very fast rising variable rate spring at the end of your suspension travel. Finally, if you check carefully and you aren't going to have any metal to metal contact with a shorter bump stop you can often just put a shorter bump stop in or even cut the stock ones down.

 

[LCB1]

Honestly, I haven't looked to see where on the control arms the bump stops are mounted, but it may not be a problem with stiff enough springs. If the bump stop is half way between the pivot bolts and the ball joint you'll have 2x as much travel at the wheel than you will at the bump stop. The closer it gets to the pivot the more travel you have.

In a lot of cases the bump stop is also a bigger piece that has some give, typically tapered also, so it becomes part of the suspension tuning. When it contacts the relatively thin tip starts compressing easily and as it compresses more it gets harder, effectively giving you a very fast rising variable rate spring at the end of your suspension travel. Finally, if you check carefully and you aren't going to have any metal to metal contact with a shorter bump stop you can often just put a shorter bump stop in or even cut the stock ones down.

Thanks, I was concerned that I went too far. The bump stop is probably 2 in thick, so trimming is an option.

 

[Silverback]

Just make sure nothing else will contact. Tricky spots might be something like the back of the control arm or the shock actually bottoming out in the body. I had a car that looked like, and everyone on the forums about it said you could go _really_ short on the bump stop which I lowered 3" and when I checked I found that the shape of the back of the control arm was shaped so it would contact a bump in the K-member after trimming very little off the bump stop.

Metal to metal contact will break parts VERY quickly...

 

[LCB1]

Just make sure nothing else will contact. Tricky spots might be something like the back of the control arm or the shock actually bottoming out in the body. I had a car that looked like, and everyone on the forums about it said you could go _really_ short on the bump stop which I lowered 3" and when I checked I found that the shape of the back of the control arm was shaped so it would contact a bump in the K-member after trimming very little off the bump stop.

Metal to metal contact will break parts VERY quickly...

I will look out for that prior to trimming.

Thanks

Larry

 

[luxstang]

Before LCB1 contacted me via PM to ask about any problems with my setup I had never even thought about it.

I had never seen my car on a lift with ramps so I always only saw the wheels hanging down when the car was on a two post lift or on jack stands.

So I put my phone into the wheel well and took a pic and I was surprised (make that "shocked"!!) to find that there are only about 3 or 4 millimeters ( 0.11 to 0.15 inches) in between the bumper stop and the upper control arm.

Now I wonder..... where does the suspension travel?!?!!

I never noticed it hit the bumpers which is weird because I usually "feel" the slightest disturbance in the function of my car.

I'm totally baffled and confused. I've been driving like this for a few years and I never noticed the upper control arm hitting the stop? I don't get it.

Marks explanation that the rubber will yield easily and thus act as a shock absorber would explain why I never noticed anything. I expected it to be a hard hit when the upper control arm hits the rubber but if it yields it would actually be hard to notice.

Maybe this is what actually keeps the tires from hitting the fenders in daily use as there is very little air in between those two.

My initial thought was to trim the rubber a little but I guess then I will probably have clearing issues in between the fenders and tires, so I'll leave it as is.

Here's the pic (Yes, it also looks like I need new upper ball joints)

 

[protouringstang73]

I've heard that some people simply just cut the bumpstop off to get the car even lower..

 

[barnett468]

.

remove the tire and the stop

lift the assembly up by hand until there is 1/2" of clearance where the arm and bracket are . . if there is no binding then install the wheel and jack it up the same amount and turn the tire full left and full right to see if it hits . . if all is good you can cut the rubber portion of the stop on half.