FSTB question

*rxm6* · 01-05-2009, 05:08 PM

Summary: Why do all the FSTB's available for the max have a bolt to attach the bar to the strut mount while other FSTB's for other cars have a single solid piece?

OK the reason for this question is two-fold. Firstly, in my head, it seems to me that a bolt system leaves room for vertical mount movement, but would prevent horizontal movement. Whereas a single solid welded piece would hold the struts firmly in place. Secondly, I ask because my BMW has a single solid welded piece and I looked online and could find no solid strut braces for the max including the expensive ones from stillen and cattman. I immediately thought of putting one together, but then thought I should ask here to see if there was a technical reason.

cfr94 · 01-05-2009, 08:33 PM

IMO the FSTB's with an adjustable bolt allows proper alignment with caster, toe in or toe out so your tires can wear evenly. If you have a solid one piece FSTB, then your tires could wear uneven and cause damage at a later date. I am by far no expert, but again just my opinion.

*essential1* · 01-05-2009, 09:10 PM

Quote:

Originally Posted by cfr94

IMO the FSTB's with an adjustable bolt allows proper alignment with caster, toe in or toe out so your tires can wear evenly. If you have a solid one piece FSTB, then your tires could wear uneven and cause damage at a later date. I am by far no expert, but again just my opinion.

I could be wrong, but that doesnt make much sense to me at all. The only thing the FSTB bolts to are the 3 strut mount bolts above each strut tower. These are stationary bolts. They have no play no matter how you look at it. The purpose of a Front strut tower brace is just to help eliminate chassis flex to aid in handling.

Back to the topic at hand though. Looking at my FSTB, which does have a bolt that allows for vertical (more so a pivot) movement. Even though this is there, the fact that it is bolted to the strut tower bolts mean that it is physically impossible for this vertical (or pivot) action to take place. The strut tower bolts would litlerally have to be loose for this to happen. Either way, tighten the hell out of that bolt. Now as far as the strength of the materials used? Cant speak for that, but that is a completely different topic. That could definately contribute to flex.

For reference, i'm using a cheapo otto FSTB that cost me $30 on ebay a few years ago.

Again, i could be wrong. And please correct me if I am. I'm no expert.

*rxm6* · 01-06-2009, 12:23 AM

Quote:

Originally Posted by essential1

Back to the topic at hand though. Looking at my FSTB, which does have a bolt that allows for vertical (more so a pivot) movement. Even though this is there, the fact that it is bolted to the strut tower bolts mean that it is physically impossible for this vertical (or pivot) action to take place. The strut tower bolts would litlerally have to be loose for this to happen. Either way, tighten the hell out of that bolt. Now as far as the strength of the materials used? Cant speak for that, but that is a completely different topic. That could definately contribute to flex.

That's my thought though is that they can pivot. In my mind, when a picture a car going into a hard turn, I know that the outside wheel is carrying the load and as such, exerting much more force on the top of the strut assembly. Vice versa on the other side, the inside wheel is exerting much less force than normal. So I would think that the inside strut mount would drop lower and the outside strut mount would rise higher, thereby, creating the pivot I'm imagining.