Frame stiffners
05-04-2011, 10:22 AM
#21
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Join Date: Jan 2011
Location: NC
Posts: 341
I know, it never seems to end and the money keeps pouring down the hole! I thought I was finished a year ago until I started reading and asking questions on the forums and basically learned all the stupid stuff I had and had done from just not knowing when I started over on a very expensive restoration to start with. I've dropped another 10K that I didn't have fixing my mistakes and doing upgrades I should have the first time. Since my car was completely restored a year ago, I have put a new Legend Gear and Transmission 3.92 rear in it, 4-wheel 12 1/4" Wilwood brakes, upgraded master cylinder, 17" AR500 wheels, new BF Goodrich tires and now building a new 302 EFI engine with TFS heads and Comp cam among other things. Now I am wanting A/C and new seats. I keep it torn down more than I drive it. If anyone wants to know how to NOT build a car, I can sure tell them. #1-There are not any friends in the restoration business! I really need to work on the frame before the luxuries.
Soon, very soon just too many other things on the plate that I need to finish first.
05-04-2011, 10:27 AM
#22
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Join Date: Jan 2011
Location: NC
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The torque box will carry the load between the subframe and the rockers instead of the floor doing it. They install from the outside and if you get a 2 piece torque box you only need to pull the carpet up enough to keep it from burning. I wish I took more pictures when I installed mine.
They slide in under the pan between the subframe and rocker. This is a 1 piece but Dynacorn makes a 2 piece, you weld the one to the bottom of the floor-to the rocker-to the subframe. Then you weld in the second piece that creates the box.
I got mine from Laurel Mountain
http://compare.ebay.com/like/1405415...=263602_325002
They slide in under the pan between the subframe and rocker. This is a 1 piece but Dynacorn makes a 2 piece, you weld the one to the bottom of the floor-to the rocker-to the subframe. Then you weld in the second piece that creates the box.
I got mine from Laurel Mountain
http://compare.ebay.com/like/1405415...=263602_325002
05-04-2011, 11:45 AM
#23
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Join Date: Feb 2007
Location: state of confusion
Posts: 7,635
Thanks. My thoughts, also, but that was what I was not wanting to hear. I guess fixing and refixing is part of ownership when you don't know what you are doing to begin with. This has been one expensive learning experience. Not trying to be stupid. but what are you going to weld to the rockers? I (not really me) can see fabricating something like in the picture but how does this connect to the rockers other than by the floor pan? Maybe I am missing something or just showing how little I know. The floor pan is basically flat to the rockers if I am understanding. This is a great idea, but in my limited knowledge I would appreciate some further explanation. I had no idea about any forums when I redid my car the first time so there is a lot wrong with it. My floor has a whole new pan in it but I really need to look at the work because it was done when I bought the shell. The car might break in half when I put the new engine in it I am building. At least it is a 302 and nothing any bigger. Thanks again for your opinion.
Where your supplemental structure (like the SFCs) doesn't fit up close to existing structure (the sills) there are ways of tying them together that are far better than sheetmetal loaded in torsion. I doubt you'd ever find SFCs made from open-section shapes like angles or channels - as such they'd only behave as panel stiffening for the floor and would not add enough torsional strength or stiffness to be anywhere near worth the bother.
Chassis torsion is the toughest loading to deal with, and you get it during cornering, hard acceleration (think engine torque reaction and where it must go), when just one wheel hits a bump or enters a sloping driveway, or when you jack up just one corner of the car. These cars weren't all that (torsionally) rigid when they were new. New cars are lots better in this respect, and part of the reason that they're all heavier than their predecessors is that they have more structure in order to meet crash performance and other things such as ride quality and handling 'targets'.
I can't see the pictures (internet filtering), so I'm not sure what sort of approach is being taken (diagonal tubes between? straight lateral tubes? closed in with a bottom panel?). But the details of the end connections, and the avoidance of sharp changes in direction where the main SFCs terminate are things to look for.
There is at least one early Mustang that has custom rectangular tubing through-the-floor SFCs that are arranged slightly diagonally in plan view specifically to line up the middle of the SFCs with the middles of the existing rails as closely as possible (eliminating the kinks in the load paths that you get when your SFCs line up inside at one end and outside at the other and run "straight" front to back as seen in plan). But you kind of have to decide to do that level of structural modification going in the first time unless you're ready and willing to rip everything out and apart and start over.
Norm
05-04-2011, 12:46 PM
#24
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Join Date: Jul 2009
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05-04-2011, 01:59 PM
#25
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Join Date: Jul 2010
Location: Indianapolis
Posts: 710
I already have my drivers side torque box installed and my pictures are not that great, or explanatory... I will be starting on the passenger side this weekend and I can take some pics that will show me installing it on a 65 with a new one piece floor pan. I will document it for you. It is much simpler than it looks, but it takes patience to get everything fit up correctly and welded in place, not so much as "Mad welding skills" just knowing where the strong metal is and where the pointless welds would be.
05-04-2011, 07:57 PM
#26
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Join Date: Jan 2011
Location: NC
Posts: 341
I already have my drivers side torque box installed and my pictures are not that great, or explanatory... I will be starting on the passenger side this weekend and I can take some pics that will show me installing it on a 65 with a new one piece floor pan. I will document it for you. It is much simpler than it looks, but it takes patience to get everything fit up correctly and welded in place, not so much as "Mad welding skills" just knowing where the strong metal is and where the pointless welds would be.
05-04-2011, 08:16 PM
#27
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Join Date: Jan 2011
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Posts: 341
What you're trying to do is make the "load paths" through the chassis as continuous and as straight as possible.
Where your supplemental structure (like the SFCs) doesn't fit up close to existing structure (the sills) there are ways of tying them together that are far better than sheetmetal loaded in torsion. I doubt you'd ever find SFCs made from open-section shapes like angles or channels - as such they'd only behave as panel stiffening for the floor and would not add enough torsional strength or stiffness to be anywhere near worth the bother.
Chassis torsion is the toughest loading to deal with, and you get it during cornering, hard acceleration (think engine torque reaction and where it must go), when just one wheel hits a bump or enters a sloping driveway, or when you jack up just one corner of the car. These cars weren't all that (torsionally) rigid when they were new. New cars are lots better in this respect, and part of the reason that they're all heavier than their predecessors is that they have more structure in order to meet crash performance and other things such as ride quality and handling 'targets'.
I can't see the pictures (internet filtering), so I'm not sure what sort of approach is being taken (diagonal tubes between? straight lateral tubes? closed in with a bottom panel?). But the details of the end connections, and the avoidance of sharp changes in direction where the main SFCs terminate are things to look for.
There is at least one early Mustang that has custom rectangular tubing through-the-floor SFCs that are arranged slightly diagonally in plan view specifically to line up the middle of the SFCs with the middles of the existing rails as closely as possible (eliminating the kinks in the load paths that you get when your SFCs line up inside at one end and outside at the other and run "straight" front to back as seen in plan). But you kind of have to decide to do that level of structural modification going in the first time unless you're ready and willing to rip everything out and apart and start over.
Norm
Where your supplemental structure (like the SFCs) doesn't fit up close to existing structure (the sills) there are ways of tying them together that are far better than sheetmetal loaded in torsion. I doubt you'd ever find SFCs made from open-section shapes like angles or channels - as such they'd only behave as panel stiffening for the floor and would not add enough torsional strength or stiffness to be anywhere near worth the bother.
Chassis torsion is the toughest loading to deal with, and you get it during cornering, hard acceleration (think engine torque reaction and where it must go), when just one wheel hits a bump or enters a sloping driveway, or when you jack up just one corner of the car. These cars weren't all that (torsionally) rigid when they were new. New cars are lots better in this respect, and part of the reason that they're all heavier than their predecessors is that they have more structure in order to meet crash performance and other things such as ride quality and handling 'targets'.
I can't see the pictures (internet filtering), so I'm not sure what sort of approach is being taken (diagonal tubes between? straight lateral tubes? closed in with a bottom panel?). But the details of the end connections, and the avoidance of sharp changes in direction where the main SFCs terminate are things to look for.
There is at least one early Mustang that has custom rectangular tubing through-the-floor SFCs that are arranged slightly diagonally in plan view specifically to line up the middle of the SFCs with the middles of the existing rails as closely as possible (eliminating the kinks in the load paths that you get when your SFCs line up inside at one end and outside at the other and run "straight" front to back as seen in plan). But you kind of have to decide to do that level of structural modification going in the first time unless you're ready and willing to rip everything out and apart and start over.
Norm
Last edited by Dennis Marks; 05-07-2011 at 08:27 PM.
05-04-2011, 08:23 PM
#28
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Join Date: Feb 2010
Location: Ohio
Posts: 315
here are some pics of when i replaced the drivers side torque box on my car if it helps...
Torque Box Replacement
Torque Box Replacement
05-05-2011, 10:05 PM
#29
2nd Gear Member
Thread Starter
Join Date: Jan 2011
Location: NC
Posts: 341
here are some pics of when i replaced the drivers side torque box on my car if it helps...
Torque Box Replacement
Torque Box Replacement
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09-26-2015 10:16 AM
1966, 1969, 67, advantages, convertible, cost, frame, liner, middle, mustang, philadelphia, post, sag, sagging, stiffeners, stiffners, top
