Chassis Upgrades

[hollywood1336]

I'm putting a 2001 Gen2 Viper motor in my 68 Charger, can anyone out there suggest some chassis stiffening upgrades / kits available. It was originally a XP 318 car. Thanks for any help

[JB400]

XV Motorsports makes one of the best "kits" around.


http://www.xvmotorsports.com/products/category/index.cfm?cid=105&lvl=1

[Homerr]

http://store.uscartool.com/Chassis-Stiffening_c_7.html

edit:  Doesn't XV Motorsports resell the US Car Tool parts?

[JB400]

http://store.uscartool.com/Chassis-Stiffening_c_7.html

edit:  Doesn't XV Motorsports resell the US Car Tool parts?

Wouldn't surprise me, but I don't know if they do or not

[Big Sugar]

Re-pasted from another thread @ protouringmopar.com   it covers the basics.

Be carefull welding subframe connectors on a rotisserie as well, Your basically hanging a shell with no doors on a odd angle with the body supported at the furthest points outward. Sure the shell is light but it's hanging sideways and once you weld in the sub frame connectors your pretty much stuck. Its really easy guys, Basically you need to decide how bad your excisting structure is. If you have or had chassis rust or significant body rust or impact damage or even a well used body that feels loose or twisty, you need to set that Chassis up straight and level BEFORE you do any welding. Remember the point of Subframe connectors is to tie the front into the rear. Which means the front section and rear section need to be LEVEL !!
if your just going old school style connectors with a 2+2 tube across the gap it's probably going to have a little forgivness in torsional twist if your welded in not quite square , BUT if your going to tie in the floor to your subframe connectors and your welding up with a slight load or twist in the shell well your gonna be stuck with it possibly out of whack .
Another misconception is you should make sure your suspension is bearing the weight of the car or have the car on a drive on lift, This seems to make sence but it's wrong, if your front suspension is out of whack or you have a overloaded torsion bar on one side it will throw off your chassis's neutral resting position, Same with the rear leafs if you have a weak leaf on one side it's going to throw off the load on the chassis mounting points. The GOAL here is to ensure your chassis is FLAT and LEVEL.
ALWays work off a Solid surface and Not a four point lift ! Simply Raise the Front of the car from the centre of the K member and position two SOLID car stands at the framerail Crossmenber below the door post area, then go to the back, pick up the rear from the diff with a floor jack and lift again positioning two floor stands at the rear spring mount crossmember, Remember you'll need to get the chassis high enough to work under with a welder, so get it high enough but stay safe.
Once your high enough use a level to check that your lifting points are Level left to right, you can do this a few ways lay somthing like a long level across the floor left to right across the supported area and shim the level so it's dead level and measure up with a tape measure to the exaxt point on each side of the chassis then shim the car as required left or right side . Do this on the front and rear, it does not really matter if the front of the car is lower or higher, what matters is that from side to side of the car the chassis is level. Then once youve done that simply place the floor jack under the rear diff and unload enought weight to support the axle without lifting the car, place two jack stands under the axles close to the leaf springs . Then go to the front and give a slight lift under the k member just enough to very slightly lift the front off the front jacks but not more than a slight float place two stand forward on the chassis in front of the tire area. lower the car and check to see the chassis at the furthest point forward is level across left to right and the rear is level behind the rear wheel arch. if you have a slight twist you can pick up that point and slightly with a twist jack or a stand and get it level. Your Chassis should now be supported by 8 Stands ALL dead level LEFT SIDE TO RIGHT SIDE at the frame pickup points.
Now at this point you know your chassis is flat, if you want to delve a little further you can reasearch the factory chassis spec diagram and confirm all your chassis measurments and tweak as required but generally the Chassis should now be ready for your torque boxes and subframe connectors and other goodies.
If you notice now that your door are out of whack there s a good chance you were running with a little twist.
Remember your running a 40+ year old car thats probably seen a ditch one or twice in it's life , has probably been jacked up from the worst possible location to jack a car (front and rear bumpers)(if that does'nt twist a chassis I don't know what will......Specially when mom and kids are still sitting in the car and dads changing a flat on the side of the road !!)
Now Fab and weld in those connectors and torque boxes and rad cradle braces and upper inner fender braces, do a bit of gusseting down below and finish off the welds on the old Crossmember laps. if your using a 2+2 tube style subfram connector be sure to weld a little angle in the middle up to the seat frame mount on the floor pan, just to tie in and help with torsion loading.
Another tip...the front bulkhead on Mopar B Bodies is a bit of a weak zone, the large side opening in the car body allows the firewall to flexx forward and back (front of chassis moves up and down forward of the front crossmember) you can add a 10 gauge steel plate along the profile of the inner forward framerail from the front crossmember forward to the front suspension mounting area to help stiffen things up. or weld uo that open seam along the framerail at the base of the firewall front to back.
You can feel the flex in your front end just by driving down the road and put your fingers up high between the front of the smokers vent window and the door opening (outside the car) or look for fatigue cracks at the base of the a pillar on the cowl and a crack in the seam weld in the front corner of the door opening at the top of the smokers window (you'll need to pull trim to see that one).

And while were discussing it, you 68-70 B body guys with cracks in your Quarter panels along the door openings right along the corner of the panel where it turns into the door jamb, Thats a Fatigue crack from constant flexing, you can weld it all you like and patch it up all you like ,it will rear it's ugly head again , it's caused by a lack of chassis support in the centre of the car, Add a set of Sturdy Subrame connectors and rear torque boxes and it solve the issue, adding a little support to the inner front framerail will help as well.

If you have access to a lift or hoist you can make it easier to fab up your subframe connectors and torque boxes and even prep all the areas for welding everything in even all the US Carrtool and XV motorsport bracing, BUT wait untill your chassis is setup level before you weld anything in.

Good luck
Ron