C4 No Flex Kit and C4 Beam Plates

[Karl]

You can see at the 14 second mark the rear end kick out to the right.

https://www.youtube.com/watch?v=3ZrNvJxDD-0

[XfireZ51]

Have had beam plates since my 84. They really do help car track straight.
Installed the V2V No Flex 2 years ago and you can immediately tellthe difference. When u go over a set of RxR tracks, you just hear the initial thud, then nothing. No secondary vibrations or buzzes. With top off, it does not completely eliminate W/S header shake.
Both highly recommended. While ur at it, go for the DRM trailing arm and rear tie rod brackets.

[Paul Workman]

Well, FIRST let me say that I do have Bill's beam plates and if nothing else, if ever you need to remove/reinstall the C-beam for any reason, you will bless the day you installed them for ease of completing that little chore - especially if you have average to large hands (which apparently, I do!): worth every penny if they did nothing else! And, as Cliff pointed out, they disburse the clamping forces over a wider area so "cold flowing" (squishing) of the soft aluminum does not result in releasing the clamping force that secures the joints (evident by the shifter raising up, among other ills, under hard acceleration).

That said, when considering the long lateral "bat-wing" mounts on the differential, AND the fact the rear wheels are independent of the differential by virtue of the U-joints on the short shafts, it puzzles me still just how the stiffening of the C-beam tie points improves the straight-line acceleration? Maybe (and this is just a hunch) the frame has a tendency to flex (twist laterally) thus (by virtue of orientating the angle of the bat-wings) pointing the rear wheels to one side...were it not for a secure attachment of the C-beam assisting to counter lateral twisting? And, if so, perhaps the stiffening bars would resolve that issue as well??

I have the C-beam plates. Love 'em. But, I never take the top off, and even after going 'airborne' a few feet and crunching the front bumper, the car does not squeak n creak like some say theirs do. I don't know why not mine? Could it be some cars joints are looser maybe? Or is it a phenomenon limited primarily to the top being off (which -=Jeff=- often does)?

Having never experienced a car w/ the no flex bars, I cannot speak to their effectiveness on a car with the top in place. And, maybe the elongation of the bolt holes in the C-beam over time is telling us that the poor C-beam is being forced to bear the burden of the frame that would otherwise be flexing w/o the added support of the C-beam? Just a hunch. But, in any case mine with the C-beam plates installed doesn't seem to squeak - come whatever the road can dish out.

I'd try the C-beam plates first before installing the bars to see it the C-beam plates do the trick, that is as long as the top is not removed. Cams and gears have risen to the top of my "to do" list, over no-flex bars (at present).