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Sub Frame Connector- Gussets

mrbone

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Hey guys,
What are you're thoughts about welding gussets in the US Car Tool sub frame connectors before they are installed?

I have made three gussets to weld in the channel just to ensure it doesn't lean when used for a 'jacking point' or ever twist.
I know it's probably overkill, but.. any reason not to?

THANKS

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As long as it doesn't interfere with the installation (causing more work), I don't see a downside to it.
 
I just installed my first set of those connectors. I, like you thought they should have more reinforcement. Did about the same as you with 1/8" flat stock. Also added a 1/2" pipe diagonally through the drivers side for the e-brake cable and cut the slots out bigger to be able to get the fuel and brake lines th through later. After all was said and done, I know that I'll never use them again. 2.5 x 1.5 tubing, a flat piece at the front, and a u channel in the rear works just as well. All brake and gas lines work with no mods, and a whole lot faster to install. Not to mention the cost savings.

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I may be wrong, but because our cars are unibody construction, the jacking points
that are specified in the service manual should be followed so as not to tweak the
frame when the car is fully assembled. Also the gussets that you are putting inside
the channel will do nothing to stiffen it length wise. You will probably bend the
channel if you put a jack on it?
 
Adding gussets is not going to hurt anything but I do not believe it is going to help anything either, all you are doing is adding weight. Once they are properly welded in they are boxed becoming essentially a square tube. Keep in mind that in a unibody car, it is the sum of all of its parts which provide the strength, everything is relaying on everything else to do its job in order to provide the strength and rigidity needed. When you add the SFC, it ties the front section to the rear and takes the strain off of the floor, or perhaps better said it strengthens and supports the floor.

Having said all this, if you are going to add gussets, take a hard look at where you might want the parking brake cable to go through the left SFC (it goes through at an angle and requires quite a bit of area). Also, in some applications you may want/need to run a brake line and/or a fuel line through one or both of the SFCs so keep that in mind.

As far as jacking the car up, I have jacked several of my cars up on the SFC without issue, the USCT SFCs are pretty stout.
 
Adding gussets is not going to hurt anything but I do not believe it is going to help anything either, all you are doing is adding weight. Once they are properly welded in they are boxed becoming essentially a square tube. Keep in mind that in a unibody car, it is the sum of all of its parts which provide the strength, everything is relaying on everything else to do its job in order to provide the strength and rigidity needed. When you add the SFC, it ties the front section to the rear and takes the strain off of the floor, or perhaps better said it strengthens and supports the floor.
Only issue I have with it is that the top is only the 18 gauge floorplan and not a shy 1/8" like the rest. Just made me feel better to strengthen them up a bit.
 
Sell those pieces of crap and use 2 x 3 square tube and you'll never regret it. The fit on those is marginal at best. When I asked the US Car Tool guys how they compensated for gaps as wide as 1/2" they replied "get a guy inside to push down on the area" !! Hmmm, isn't that putting stress where it doesn't belong !! Here's how I did mine:

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Ive installed 3 sets of USCT SFC's and would say that while they do require some fitting I really like them. Of course there is more than one way to accomplish a given task.
 
Thus allowing flex in the pans.

Yikes !! So you cut HOLES in the pans and then you don't reattach them. Makes NO sense at all ! You're installing connectors to make things rigid - including the floors !!
 
Take into consideration the original stiffeners were bolt in units. No cutting required. Wish I had taken a picture of those but had no camera that day many years before cell phones with cameras.
 
John at US Car Tools said to run a full length bead all around the frame connectors. Thats how mine are. And it turned out very nice.
 
Hey guys,
What are you're thoughts about welding gussets in the US Car Tool sub frame connectors before they are installed?

I have made three gussets to weld in the channel just to ensure it doesn't lean when used for a 'jacking point' or ever twist.
I know it's probably overkill, but.. any reason not to?

THANKS

View attachment 1065766

You can add gussets if you want. If I was going to add gussets I'd drill holes in the connectors and slide a small length of tubing thru the holes and then weld on both sides. That provides you with a gusset but it also gives you a pass thru in case you need to route wires or cables in those areas.
 
When using 2 x 3, the 2 is width and the 3 is height. The pans get cut in the rear floor area and then welded to the connectors.
I usually notch and box the opening area of the 2 x3 height so i don't have to enter the floor pans. Us car tool has their way but sheet metal floor pans provides no Structural value in tying to the floors.
 
The floors ARE the structure on a unibody. Their the only thing that ties the front and back of the car together, that and a little bit of roof, again sheet metal. By welding the sub frame connecters to the floor it's way stronger. Imagine grabbing a wall stud, it's only nailed on both ends, it's wouldn't be that hard to rip one out. Now imagine grabbing that same stud that also has plywood nailed to it, your not going to move it. Try it with just sheet rock, less strong, some may argue like a sheet metal floor, you still aren't going to move it.
 
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The floors ARE the structure on a unibody. Their the only thing that ties the front and back of the car together, that and a little bit of roof, again sheet metal. By welding the sub frame connecters to the floor it's way stronger. Imagine grabbing a wall stud, it's only nailed on both ends, it's would be that hard to rip one out. Now imagine grabbing that same stud that also has plywood nailed to it, you not moving it. Try it with just sheet rock, less strong, some may argue like a sheet metal floor, you still aren't going to move it.
Actually you would think so but not in reality ther heavery sub frames are the structure. The floor pans always have had a buckle problem in the past. But hey your entitled to your opinion.
 
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