Tom400CFI

Barely. It has frame "rails", but they're stamped tin, spot welded together. The C4 and up is "unit body" too; just the plastic body panels bolt on.

-=Jeff=-

So far I can tell a difference.. needs tweaking on the Pass Side though

boonie c4

How Much dose it cost?

-=Jeff=-

I have a GP on my website

http://www.vettextc.net

jakers

These are nice and I can see that they would help by firming it up but the cost is currently too high for most of us.

I bought a used Cross Frame for $200 awhile back. I installed it but ran into exhaust clearance issues. Then along came the rear suspension/clutch project. The car is going back together now and I will have to sort out the Cross Frame fitment with my exhaust. This dang Cross Frame weighs a ton and it is counter intuitive to keep adding weight to "fix" C4 problems. If they had done this at the factory these cars would have ended up weighing in at 4000lbs!

Here is a shortcut to the Frame Brace.

http://www.vettextc.net/MY_ZR-1/Frame_Brace_GP.html

pantera1683

Jeff,

Any updates?

-=Jeff=-

I am away for the Corvette currently. If I get a chance I will call Jason

corvetteronw

I have been driving my 91 coupe with the hatch roof removed and can really feel a difference.
The car feels as if I just drove it off the showroom floor. I can drive over railroad tracks without slowing down to 10 mph. I can take the curves on my local "Corvette therapy" twisty road much faster. The car feels completely different to me. I am real happy with the setup. No more rattles either!
She is temporarily out of service as I am replacing most of the exhaust system along with modding the intake system to include new Bosch IIIs from FIC injectors.

pologreen1

I am interested in a real test between the stock X brace, and R&D brace. I know the stock one weighs very little, but I wonder how that affects things, compared to R&D.

I'd be happy to trade you a light GM brace for you big heavy R&D brace.

PLRX

I could see if it would cross over but, that is not the case.

I'm not an engineer but, would those make the chassis stiffer/stronger?

pantera1683

I wonder how hard it would be to tie the left and right sides together with the frame braces

SQUIRMIN VERMIN 84

any bracing that would triangulate?

pologreen1

-=Jeff=-

According to Gordon you need to adjust the bars to get them right. I think I have them right, the car is tight, with the top off, much better then when they were first installed. I think I could adjust the driver side again maybe

Speculate all you want about these, as far as I am concerned these work and work well..

Moon86

I've been reading this thread with interest since my 85 really loosens up with the top off. It would seem to me that the rods might bow the frame in a slight upward direction to counteract frame sag. After all, the windshield frame and the rear hoop can't move towards each other when the roof is in place. When the roof is off, the frame can sag in the middle and when the front end goes over bumps it can flex even more. I would be curious to find out whether the rods get adjusted with the roof on or off. The removal of the sag by the rods could probably be measured if it was setup carefully enough.

romankrzy

When you say "hatch roof" are you saying the hatch glass? I am now on the hunt to eliminate the shakes and rattles on my 93, it's my first Corvette. I just replaced the AC Delco shocks and that helps but it seems to be just the beginning.

-=Jeff=-

when I adjust them.. Hatch is closed completely (I have a vent in 99% on the time)

roof is on and hood and doors are closed as well..

corvetteronw

I meant "targa top removed.

romankrzy

Any ideas how this device ( Targa Truss ) compares to the Frame Brace? It's a few hundred cheaper but it attacks the issue from the top vs. the bottom and I would hate to waste my money.

http://r-dracing.com/targa-truss.htm

avigar

How would you calculate how much tightening of the rods is required? Trial and error I assume. Is there an initial setting that you would start from?