Stress points?

[lexluthr69]

A few of the roads I drive on here are not the smoothest. There are quite a few dips and bumps that if I'm forced to ride the edge of the road, the chance of me bottoming out greatly increases. My question is:

Where are the stress points and/or what should I be checking if I frequently bottom out?

I figured the obvious would be strut to spindle connections, and strut to chassis mounts, but what else?

Luke

 

[300]

Assuming you're using stock wheels and tires, it shouldn't bottom out. If it does make sure you have the right springs, struts and shocks for your car.

 

[NastyStang113]

There's no reason why it should be bottoming out to that degree unless you've hacked up the springs.

 

[lexluthr69]

I do bottom out and it is why I'm worried about any stress points that might not take to kindly to it. I'm running 18" GT4 wheels with 40 side wall tires and un"hacked" springs in my sig. While I'd love to not bottom out at all, it is a fact of the roads I drive on that occasionally it happens... more often than I'd like. So for that matter, I'd like to focus on the stress points and not the bottoming out.

Luke

 

[NastyStang113]

Okay so where are you "bottoming" out? The bump stops in the rear won't allow it to go any further to allow any type of "bottoming" out. The front the only thing that could rub would be the front bumper. If you had something else rubbing you'd be stuck and framed out.

 

[lexluthr69]

In the front, would it be possible to completely collapse the front springs? I know in the rear you have the bump stops to help, but what does the front have, if anything, to protect it?

By bottoming out, I mean that feeling of complete collapse where the only thing providing suspension for your butt is the seat your sitting on. So in that case, the bump stops would have been touching.

 

[NastyStang113]

The front struts have bump stops built into them, I believe. Also, do you have Tokico D-Specs or the unadjustable set?

 

[lexluthr69]

I have the non-adjustable Tokicos.

It seems like we're discussing whether or not I've actually "bottomed out". To me, that refers to complete collapse of the suspension, where either you've reached full spring collapse, or you've hit the bumpstops. Either way, it's not good for the car. What I want to know is where I should be concerned about.

I know I'm bottoming out... So again, what are the stress points I should be looking at?

 

[300]

You seem to be accepting the idea of bottoming out as normal, it's not. Forget about checking the stress points until you fix the problem (ie. bottoming out).

 

[o0Dan0o]

You seem to be accepting the idea of bottoming out as normal, it's not. Forget about checking the stress points until you fix the problem (ie. bottoming out).

He might not hit the bump-stops with the stock springs, but either way it isn't that difficult to bottom-out these cars, though difficult enough to where I would have to deliberately try to do so.

I have the non-adjustable Tokicos.

It seems like we're discussing whether or not I've actually "bottomed out". To me, that refers to complete collapse of the suspension, where either you've reached full spring collapse, or you've hit the bumpstops. Either way, it's not good for the car. What I want to know is where I should be concerned about.

I know I'm bottoming out... So again, what are the stress points I should be looking at?

First, the only major stress points will be at the bump stops, as that is what you're hitting when you bottom out, you have one on every corner. The chassis on these cars are more than strong enough to take bottoming out on occasion, but looking over the suspension arms and mounting points on occasion might not be a bad idea.

Second, I drive on some very bad roads every now and then, and have never had an issue with bottoming out (though I have the stock springs which give me another inch+ of travel). One solution may simply be to drive a little more cautiously.
Dan

 

[TBrad]

IMO...

If I was worried about stress on the unibody frame. I would install some full length sub-frame connectors and torque box braces like these...

View attachment 264241



Otherwise the only other place I would worry about the stress on the frame is at the bump stop areas. I wouldn't think there is much you can do about reinforcing those areas accept installing front and rear strut tower braces... other than making some kind of custom reinforcement.

 

[lexluthr69]

Dan,

Thank you. While I do try to drive cautiously most of the time, occasionally last second maneuvers on country roads put me on the less than comfortable portions of the road.


Tbrad,

I hadn't considered subframe connectors on these cars, as much as I had previously on my old '01 GT. I always considered them more of a suspension twisting and turning prevention than anything else. I'll have to look into those more.

Thanks again ya'll.

 

[Hicompression]

I've got fresh Ford Racing "K" springs and I've bottomed out in the rear against the bumpstops going over a small dip at about 40mph. I am also running the Tokico non-adjustable "blues" front and rear.

The Eibach "pro" kit is the same as the FR kit. So...in the rear you are bottoming out with contact between the bumpstops and the frame. The bumpstops are just outboard of the springs on top of the axle on each side. If anything, your bumpstops will compress and crush over time since they are rubber. I can't see you hurting the frame.

I have not yet bottomed out in the front, but if it did it would occur when the strut has reached full compression. There is a bumpstop on the strut rod under the dust cover. This would be hitting against the strut mount that is mounted to the top of the spring. If you bottom out a lot in the front, you may have blown out your front struts. I would change them out and replace with adjustable struts.

 

[o0Dan0o]

The other option is to get a truck

 

[TBrad]