As many of you probably know by now, we recently finished a design for C4 Fixed Position Projector Headlights. We started a thread at
http://forums.corvetteforum.com/c4-g...-you-want.html
to find out what the C4 owners would like for their cars. One recent suggestion was a Frame brace system that the rest of us can afford. I know there are several systems on the market in the $500 range, but I believe we can make a competitive product closer to the $300 range with increased functionality (like longitudinal and X bracing). Right now I am looking into the bracket design options to keep the system light but extremely rigid. Steel is my first thought, but I will also look into aluminum depending on the space I have available. For the X bracing, I am looking at simplicity for removing the exhaust. How many people are concerned with difficulty removing the x-brace to remove the exhaust. I can make a removable plate if it is a big concern. Email
rppcorvette2@gmail.com
for updates and for initial product specials. I am considering selling the first 10 sets at cost to those forum members that are interested in helping us evaluate new products(particularly those that drive hard or autocross).

 

I would definitely be interested for the price, keep me up to date with the progress.

 

Interesting.

I am having the convertible x-brace installed on my '95 coupe, but am running into fitment issues with longtube headers.

 

If you are interested in this project, send an email to
rppcorvette2@gmail.com
I estimate prototypes could be ready in less than 1 month if there is enough interest.

 

I would be VERY interested but have a semi-unique exhaust system. Lawrence-Keech Side Effects Side exhaust AND it's bolts to unique headers (Vette Tech).

I wonder about the challenges. It's jacked up though. I could provide pics for an opinion about feasibility (or challenges).

 

My 2 cents is this. The chassis stiffners like the bars from Vette to Vette might help in feel/squeaks and so forth. Actual handling difference I think will be next to nill and NOT worth the cost.

Running a stifferner like this would bump be from B Stock right past B Street Prepared to a Prepared Class, WITHOUT any other mods.

A test was done back in the C4's hay day, auto-x with top on and off, with a pro driver. Times where basically the same.

There is a BIG difference in FEEL top on and off in a C4, no difference in actual lap times. I doubt a frame stiffener will make any difference in actual performance.

Unless, someone can show me hard data like lap times with same setup, track layout, similar weather conditions, tires,etc...with and without the stiffner. I'm not interested. Added weight to the car is NEVER a good thing, unless it helps balance it.

Long story short, the C4 chassis, is what it is. Don't like it buy, a C5 or C6.

 

Here is a quick photoshop of the design I am considering. It incorporates both the X-Brace and Longitudinal Bracing.


Here is the Exotic Muscle design that runs about $400.


Here is the Vette 2 Vette design that runs about $500.


I am looking into several possibilities for materials:
-Aluminum: Light weight, but I am not sure if it can handle the constant abuse that the system may be subjected to.
-Mild Steel: Excellent strength and cost effective but heavy
-Chromoly Steel: Very strong and about 30% Weight savings over mild steel
-Titanium: Light weight and very stong, but also very expensive

I am initially leaning towards Mild Steel or Chromoly Steel(with black powdercoat of course). Another concern I have is level of adjustment. I have seen a couple designs with eyebolts to tighten the system, but I really don't see the advantage. I am thinking that elliptical mounting holes would provide quite a bit of adjustment without adding the cost of adjustable eyebolts. For the center section, I am considering how to form the X and still make it easy to remove to get to the exhaust. I think the minimum will be 8 bolts in the center to provide adequate design support. Let me know what you think and be sure to email us for more info and a chance at the initial offering price break.
rppcorvette2@gmail.com
Thanks,
Brandon

 

While a small market, the early cars that lack the convertible x brace mounting holes would benefit from this as well. I had the vette2vette stiffener and supposedly all cars coupes & convertibles 86 up had these mounting points. My car is an early 87 and lacked the added "bump" in the forward frame points to mount the bracing. Perhaps some bolt on or weld on brackets to accomadate your new design so they would fit not only the later cars, but the early models as well would be beneficial. Just a thought.

 

Very cool. While very interested, the headlights will be my first priority. Which is a mid to low priority as it is (although i'm currently having to help my headlights finish rotating).

I'm riding fairly low, so ground clearance will be an issue. I'd also recommend checking out a convertible, I believe the cross section in the middle bolts to the car as well. That's how you really firm up the chassis. Would certainly need to make it fairly easy to access the underside of the car. I've been under there WAY too often lately!

 

Yup I was under the car at the shop today. There are holes along the GM brace that attach to the floor pans (not just the center plate, which actually doesn't even touch the floor pans) .

 

I would be interested in being a test mule! I would think chromoly would be the way to go!

 

Add me to the list

 

I am seeing a lot of support for this project, so I will be hard at work this weekend. I am thinking powdercoated chromoly with welded plate steel and round tubing will make this affordable and very strong. I will post updates as I progress. We still need a couple more people interested in initial testing, so email
rppcorvette2@gmail.com
Thanks,
Brandon

 

I'd see if you could make a bracket that could connect to the c-beam/transmission mount. Just make everything more rigid. Not that I EVER want to touch those C-Beam bolts again.

 

Seems like you'd have to drill the c-beam or be able to find (or deliver the kit with) longer bolts.

 

I'd just do longer bolts. Could probably easily just make the c-beam adapter optional. Although the more I think about it, the reward vs the effort probably wouldn't be worth it.

 

I think connecting the differential/transmission brace to the system would have a negative effect. What you want to accompish requires connectors from the rear frame to the differential. I may look into suspension components like those later.

 

Due to varying age and condition in the C4 market, it would make sense to design a brace that doesn't need to be removed once installed. Probably the average C4 owner makes upgrades and repairs in stages for example.

1. Exhaust.
2. Rear seal repair where the transmission needs to be dropped.
3. U joint repair on main shaft.
4. Rebuild transmission.

X Brace is probably pretty simple to remove but the other solution is convenient. I'm looking to purchase a brace solution soon. I want to be one of the first 10 prototypes.

 

I would be interested as well

 

Add me to your list, thanks.