Structural sills, no torque boxes

[GeoffC312]

https://www.studebaker-info.org/AVDB2/AvantiRQA/67QA0151/67QA0151x07112018/67QA0151x07112018b.jpg
https://www.studebaker-info.org/AVDB2/AvantiRQA/67QA0151/67QA0151x07112018/67QA0151x07112018.html
https://www.youtube.com/watch?v=1n5Oq_yyG_o
https://www.youtube.com/watch?v=CaAAdalko50
and has done away with torque boxes. That car's frame has also been 'sturdied' as seen in one picture.

Normally what, the frame bolts to the torque boxes and the torque boxes are adhered to the body, yes? If the torque boxes are omitted, the frame must bolt to something. The quest then becomes to create that something. What hits me right off the bat is, I would borrow a page out of the C5 & C6 'Vette book, sandwiching balsa wood between two fiber mediums. Or just sandwich three to five fiber mediums together, oriented in different directions. The final creation also needs threaded inserts or similar solution, to anchor the bolts.

My basket case needs some underside work and I too may omit torque boxes.

Edited December 7, 2022 by GeoffC312
I think my text hid some details. I extricated the links and killed my text.

[Kodjo]

It's not that simple. A torque boxes is called torque box because it has to make the car stiff. They are not there just to keep the distance between frame and body.

[mfg]

The torque boxes or " hog troughs" also lend  support, and anchor the rollbar..such as it is!

[Dwight FitzSimons]

The roll bar "such as it is" isn't too bad.  A local person flipped his nearly new '64 Avanti on a peaked (sharp) hill on a narrow road.  The car slid, nose first, on the pavement into a pole.  The windshield header was pushed down maybe 2 inches and roll bar not at all (that I could discern).  He was going probably well over 60 at the time.  So, it did its job at street speeds.

--Dwight

[mfg]

29 minutes ago, Dwight FitzSimons said:

The roll bar "such as it is" isn't too bad.  A local person flipped his nearly new '64 Avanti on a peaked (sharp) hill on a narrow road.  The car slid, nose first, on the pavement into a pole.  The windshield header was pushed down maybe 2 inches and roll bar not at all (that I could discern).  He was going probably well over 60 at the time.  So, it did its job at street speeds.

--Dwight

The stamped steel " roll bar" found in original Studebaker Avantis is more substantial than what is found in later Avanti ll's (with moon roofs)

[pantera928]

5 hours ago, mfg said:

The stamped steel " roll bar" found in original Studebaker Avantis is more substantial than what is found in later Avanti ll's (with moon roofs)

I hope never to have to test that statement!

[GeoffC312]

So I should have clarified in the beginning: I know I'm not just applying a filler between the body and frame. It somewhat is, though I know said filler needs to be of a certain conformity. I'm also aware the roll bar attaches to the torque boxes. I am also contemplating replacing the factory stamped steel bar with DOM steel, like an actual roll bar.

This has already been done, and the car to feature it sustains road course beatings. I'll picture it here, but this pic. and more are linked in the initial post. I'll stop posting links inside of my written text. Maybe that hid too many details?

Carbon fiber is strong, as this segment shows, https://www.youtube.com/watch?v=hjErH4_1fks. Also, I read about Chevrolet sandwiching balsa wood between composite materials. That made the floor 10× stronger than using composites alone, plus balsa filters out noise and vibration.

Okay, so culminating all of the above: I am taking aim at creating a rustproof substitute for stock torque boxes. I may use chopped mat fiberglass, I may use carbon fiber, I may include balsa wood, I may pick everything listed above, and some materials unlisted. I just want to recreate "structural fiberglass sills in place of hog troughs" as seen below.

Now that it's better explained, and better visualized, how do you suppose this was done?

Edited December 7, 2022 by GeoffC312
Nuked links; just typed out URL addresses

[mfg]

Sounds real interesting...probably stronger than original.

PS...The Grantellis installing roll cages in Bonneville #8 & #9 is an indication they didn't have complete confidence in factory 'roll bar'.

Edited December 7, 2022 by mfg

[Avanti83]

It would be nice to see a few more shots of the underside, particularly with the body on frame, but it looks like they did exactly as you described. They apparently boxed in the rocker panels and other areas under the body and then mounted it to the frame. Exactly where the mounting points are located is not all that obvious. 

They could have used wood or even foam in the areas like the rocker panels to fill the void and provide rigidity.

It must work as the cornering shots in the video look like the car handle very well. 

The early corvettes didn't use hog troughs so they probably just used more box sections than the Avanti's.

https://www.rkmotors.com/blog/Corvette-Bones-Growing

Good luck on your project and keep us in the loop.

[GeoffC312]

I'll definitely be documenting my progress with my basket case, both in stills and in videos. There is so much I want to do to it, and don't mind at all making my alterations publicly available. I have reached out to the owner of the Targa Tasmania car, to learn more about it. As you say, it would be great to see more shots of the frame and body together.