If anyone is trying to sell me something to stiffen a chassis and not willing to talk in pounds per degree of flex it's just another untested part. Kind of like buying heads with no flow data or springs with no lbs/inch data.

 

Not even with a full 10 point roll cage ?? When we built my roll gage we added alot of bars going across from rail to rail .

 

I've thought about that. It would then fit the original design idea.

@Red L98, ok maybe with a 10 point cage. I should have said, with adding a lot of weight. That cage would be heavy.

 

Add me to the list as well!

 

LOL. Id say that worked.

 

Here is an updated picture of some changes I made.

I decided to increase the size of the tubing and remove the outer bars. With the design changes I made, the outer bars became unnecessary. I also simplified the mounting points although that can't be seen from this picture. Based on the fact that my car has 3 inch exhaust that hangs 1.5 inches below the floor, I am considering 2 x 3/4 inch tubing for the brace. I think that will minimize impact on ground clearance while adding a significant amount of stiffness. For the center section, I have two connectors, a U shaped bar that goes above the exhaust and sits just below the trans/diff brace, and a flat bar that goes below the exhaust. I am working on keeping the center bar close to the trans/diff brace so it can be bolted together for those that are interested in making the connection. I am also keeping the design simple, so spacers can be used for any fit adjustments. The previous design was going to be too expensive and heavy to produce, so I made a few tweaks. I am also looking into an improved targa brace that will be a little more convenient than what is available now.

 

RPP,

why dont you put in some transverse braces.

There are places to mount them to.

All you need to do is remove the rocker panel covers and weld some heavy gauge 'L' brackets hanging down from the rocker panel lip.

The c4 corvette rocker panel is also the frame rail

Once you have L brackets hanging down from both sides of the car, now you have a place to mount transverse square tubing (running across the car).

The weak spot becomes the L backet but you can always add another leg to it on the inside of the rocker lip. Of course welding by the fuel line always makes me nervous.... but it can be done! This is what I want to eventually do.

This is what I did on my car (welded some square tubing transverse wise across my vert's x-brace and bolted it on both sides to a pair of 'L' brackets I welded off the frame rails).

I also have a 6 point cage with permanent diagnonal sidebars and this transverse beam I added occurs right at where the sidebars affix to the frame rail/ rocker.

The cool thing is it all looks pretty clean because the fiberglass rocker panel covers cover up where the 'L' brackets were welded to the frame/ rocker panel.


Ill see if I can dig up a picture.

 

I have thought about braces at the sides, but I can get the most value with the least weight by mounting to the front and rear frame sections. The most difficult part of the design is how to connect the center portion since many people have various aftermarket exhausts that hang below the floor panels(mine hangs about 1.5 inches). I think I have a good solution, but I will wait until after testing the prototype to assess.

I do have a request: Can you take a picture of the rear mounting location design for the original convertible brace. I have seen the brace, but I would like to know how GM designed the rear mounting points. It may give me some better ideas for the rear brackets.

Thanks,
Brandon
rppcorvette2@gmail.com
www.riceperformanceproducts.com

 

Very interesting. I hope you succeed.

 

God that looks heavy .. lol My whole roll cage was around 80-100 lbs , I bet that thing is just as much .

 

Like many of you, the first time I took the top of of my '94, I was shocked at the cowl shake and general "floppy" feeling of the entire car. So anything that would help reduce that would be great, and I want to encourage those vendors and individuals that are still trying to improve our C4s. The question that I have is whether the approaches given in this topic are aimed at the street crowd or at the folks who will use it on the track. Race tracks (for the most part) have well maintained and fairly smooth surfaces. So chassis bracing or additions make sense in that environment. However, I use my car exclusively on the street as an everyday, go anywhere, vehicle. As such, I encounter speed bumps, pot holes, and all sorts of trash laying in the roadway. My car is at stock ride height and the bottom of the car is always coming in contact with potentially damaging objects. So when I see additional bracing that appears to reduce the ground clearance even more, then I question its practicality and usefulness in the real world that most of us inhabit. Just one man's humble opinion.

 

Any chance you could make a copy of one of the targa braces at an affordable price and actually have it available for purchase? Solves all the problems....no cowl shake, no loss of ground clearance, easy to put on, no weight gain....all positives.

 

When will the first 10 braces be ready?

 

how would he know? these things take time....

 

I still say build it thin and flat tucked right onto the floor of the car.

 

No...really???

 

did u read the thread? he is still in the R&D stage.


yes really.

 

 

Of course I read the thread. My response was cynical. It doesn't hurt to ask. Is he planning on taking his C4 with the brace installed to Nürburgring Race Track?

Of course it requires R&D.

 

lol. looks can be deceiving.

that weighs 45 lbs. (25 lb factory x-brace + 20 lbs of steel rectangular bracing).

However, boxing in a factory x-brace (as some have done) adds just as much weight from my calculations on the length/thickness of steel and the density of steel.

the 6point cage in my car weighs 40 lbs.

Ideally, id like the aftermarket manufacturers to make braces/cages out of titanium. However none of the aftermarket manufacturers have stepped up to the plate.

If you have a better idea how to tie the two sides of the frames together underneath the car -or thru the passenger compartment from one side to the other, then id like to hear it.

Top Sidebars connecting the main rollbar to the top of a front hoop following the windshield looks like absolute crap IMHO on a vert like mine.

So I put the transverse connection underneath the car.

I do have non-removable diagnonal sidebars for max stiffness. Im fine climbing in over these.

Id like to see 'removable' top sidebars for vert owners.