Body Flex

[drewcrane]

My challenger has the same problem ,

my question is do Cudas do the samething?

[rhamson]

My challenger has the same problem ,

my question is do Cudas do the samething?

I have not done a Cuda but I would imagine the same thing will apply. I have seen the seam on hot days on dark colored Cudas so I guess it is the same.

[Changin Gears]

I have always thought that the trans/driveshaft tunnel adds strength.  But with a 4 speed, you cut a big hole in it and cover it with flimsy metal, making a stick car weaker...

[rhamson]

I have always thought that the trans/driveshaft tunnel adds strength.  But with a 4 speed, you cut a big hole in it and cover it with flimsy metal, making a stick car weaker...

How so? If you do it correctly by not cutting the cross trans support and by leaving the metal floor above the support intact you have essentially the same area support structure. By placing the 4 speed hump over it and welding it solid around the edges you complete the floor covering in a different configuration. I think a set of frame connectors should be incorporated in any high horse power combination that one would consider if there was any question to the integrity of the unibody structure.

[Changin Gears]

The thickness of the metal used to in the floor has got to be twice that of the shifter hump.   

Seems like thike this would add to the cowl shake issue convertibles have...

The hole cut in a b-body floor is probably less than 1', maybe double that for an a-body, double that again for and e.

[rhamson]

The thickness of the metal used to in the floor has got to be twice that of the shifter hump.   

Seems like thike this would add to the cowl shake issue convertibles have...

The hole cut in a b-body floor is probably less than 1', maybe double that for an a-body, double that again for and e.

Maybe you are right but it would be hard to prove as the unibody flex without any modifications is well documented. Even with a full frame such as is the case with a truck, for instance, has a lot of flex unless you box in the frame.
I have a 1972 Challenger that was a 340 Auto and I have converted it over to a four speed and stiffened the frame everywhere I could and it seems to be stronger even with the new hole in the floor.

[nr1freak]

i have a '70 hardtop cuda and that seem was filled with lead.
i did notice, before getting the car blasted, that the lead seemed to be bulging out just a little, perhaps due to a bad leading job but my guess is that, because of the flexing of the panels, the lead was "kneeded out" with years passing and, because it's lead, didn't go back to it's original shape, paint wasn't cracked though!
it was a slant six original so not a lot of "torque damage" but as i'm installing a 440 now, i will be putting in torque boxes, subframe connectors, swaybars front and back but most importantly, i will be strengthening all the seems inside and out with extra welding just to make it more ridgid!

[ChallengerGary]

There's a video out  by XV Motorsports, that shows how much body flex there is in one of these old cars.   Then they show the difference that their reinforcing kit makes.  You won't believe it.  It's amazing when you see it.

I just finished up a 69 Road Runner in which I installed torque boxes, sub-frame connectors, tubular lower radiator support, and upper fender/cowl supports.  The car is now rock solid.  It has virtually no body lean when going around a corner.   It no longer handles like a 1969 land yacht.

[brads70]

US CAR TOOL 1970-1974 Mopar E-Body Cuda/Challenger Uni-Body Rigidity Test

[72cudamaan]

US CAR TOOL 1970-1974 Mopar E-Body Cuda/Challenger Uni-Body Rigidity Test

I saw the video and I'm on the fence on this. Sure, you hang weight that far from the car and it's gonna flex. But
how bad is it under normal conditions? I assume these braces can't be installed unless the car is sitting on a flat surface
with the wheels on the ground? Probably not a good idea to do while the car is on the rotisserie.

[rhamson]

I saw the video and I'm on the fence on this. Sure, you hang weight that far from the car and it's gonna flex. But
how bad is it under normal conditions? I assume these braces can't be installed unless the car is sitting on a flat surface
with the wheels on the ground? Probably not a good idea to do while the car is on the rotisserie.

I installed the USCartool kit and the strength of the car is amazing. The difference in price is astounding and you get the same results. I talked to the owner at Carlisle and he said they install the kit on their cars on the rotisserie. The car has to be in good structural shape though. I turned the car up side ways so that there was no flex and the car measured out fine.

[brads70]

I saw the video and I'm on the fence on this. Sure, you hang weight that far from the car and it's gonna flex. But
how bad is it under normal conditions? I assume these braces can't be installed unless the car is sitting on a flat surface
with the wheels on the ground? Probably not a good idea to do while the car is on the rotisserie.

Put a jack under the k-frame and take note on how much it goes up before the wheel come off the ground.
 I think I'm gonna bite on this one. Need something to do this winter anyhow!    This design looks MUCH better that their previous one! 
This should make the torsion bars more effective also as now the body is in effect a torsion bar.  After 43 years of flexing I would think metal fatigue/cracking  might be a problem at some point.
I know after I installed the torque boxes and sub-frame connectors I can jack the car at the sub-frame ( front or rear) and both wheels come off the ground MUCH sooner that before.
I'll make my own rad support brace not worth the money for what it is to me , but the inner fender brace.... no way you could make that cheaper ( time and material)

[johns cuda shop]