I have noticed through the years of working on these cars that the big block 67/8 fastback cars tend to have a dent in the roof right above where the driver sits. I have always believed that this was due to twisting of the body. I have never seen it on big block coupes and I'm not sure why. For my money if you want to stiffen the body on the early cars the first step should be torque boxes and then subframe connecters.

Dennis after reading your post it sounds like you are talking about just running a channel from the front of the front frame to the back of the front frame. That will not do much for you. consider doing torque boxes first and then subframe connecters.

 

Ochohill, give at the end of what pillars?

 

made them basically using 11 awg box tube.

 

I agree about their customer service. They are very quick to reply and very friendly to deal with. That is what sold me, also. How hard was it to install?

 

I have tried to do a little homework and I am aware of the benefits of torque boxes. My problem is my car is completely restored and in my limited wisdom, it looks like all the welding will require the interior to be pulled out and much of the Second Skin insulation I have rolled on the floor will need to come out. Am I thinking correctly or making too much out of it? I might have to do this anyway to weld the sub-frame connectors in. Any suggestions?

 

You did one good job. Awesome looking frame. You have a few more technical skills than me. Looks like a factory frame. What size tube did you use?

 

If I had a restored car torque boxes would look less out of place than SFC's and do more good than SFC's alone, but thats just my opinion.

I also feel that store bought sub frame connectors without factory style torque boxes installed may not be the best way to go,the floorpan extensions are thin, and if you have an original floor, or worse one that has been "patched" around the toe board your car is extremely flexible, welding from the extensions to the rear frame area alone will help some, but its not as strong as you think if you are counting on the floor and that front extension to handle any real twist.

The rockers (if in good shape) can offer the same kind of twist stopping reinforcement and the front frame being connected to the rockers with torque boxes would be a huge benefit.
The rockers are further out from the center line than the SFC's and provide a wider geometry, and will do quite a bit to add stiffness to the car. Sub frame connectors that only mount to the front floor pan extension and to the rear torque box could just twist with the floor because they are narrower and only connected at two points.

For best results I would want to weld the SFC to the floor, or even penetrate it for the best results. If a car is a post 68 and has boxes already then go for it, but a 65 needs boxes first IMHO.

But, its all just my opinion.

 

It's still in the box Soon, very soon just too many other things on the plate that I need to finish first.

 

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.

 

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