Complete floor replacement advice

[Moparjake]

Hey guys,

I am getting ready to do a full floor pan replacement along with subframe connectors in my 66 Valiant. I have a rust free donor pan, welder, rust ecapsulator and some decent mechanical capabilities. I figured i would ask you more knowledgable folks a few questions before i tear into this thing...

Where do you normally place jack stands and whatnot to keep the cars unibody from tweaking when this type of surgery is done. I am assuminging that by adding in the subframe connectors prior to removing the pan will help some?

When installing a complete pan where do you typically cut it to fit it in(across the middle, in half, ect)

Is there anything i should look out for?

Does anyone have any pictrues or whanot of this being done?

Thanks for the help!

-Jake

 

[mcnoople]

Wheel ramps are preferable to jack stands. If using jack stands 2 under axle tubes and 2 under front frame rail as far forward as possible. I like to put them between the front and rear k-member mounting pad.

To remove your old floor most people use a spot welder bit to drill out the spot welds. I personally prefer to grind them down with an angle grinder. I don't believe you need to install the frame connectors first if you have it supported correctly. Make sure the doors open and close properly without dragging and jamming before you weld anything in solid you don't want to weld your car into a tweaked position. If you haven't purchased the frame connectors yet look into the ones made by uscartool. They are the best looking piece I have seen and their other product lines have good reviews.

While you have the floor out it would be a very good time to add some additional bracing and reweld the torsion bar crossmember socket. The original welds were barely adequate on many cars. I have seen cars that were only welded on roughly 1/4 the diameter of the socket on 2 sides.

 

[daliant]

I would place the jack stands under the rear subframe just ahead of the spring hangers and on the front subframe near the torsion bar crossmember and then put a floor jack under the K frame just to keep the weight of the engine from pulling the front of the car down. While the car is jacked up take a look at the door gaps to make sure nothing is out of wack. Then tack weld the subframe connectors in first (assuming they are the type that dont pertrude through or weld directly to the floor pan) this will keep the car from sagging while the floor is out. Next step cut the floor out, then weld the subframe connctors in while the floor is out, they will be easier to weld the front half while the floor is out.
An air chisel works real good for busting spot welds (drill them out first) but you also run the risk of messing up the parts of the car that you need to save so be carefull. I would cut as much of the floor out that you can with a cut off wheel or sawzall and the deal with the rest of the pieces that are spotwelded to the rockers and crossmember, you dont get extra pionts for removing the old rotten floor in one big piece so cut it into as many little pieces as you need to.
If you have to cut the new floor pan I would slice it right down the hump, it will be easier to dress down the weld on the top and the transmission and driveshaft will hide the seam from the bottom, just tack weld the two pieces together once you get them into the car before welding them in so they dont move around from each other while fitting them to the car.

 

[BIG DOG]

I used a spot weld cutter and a air chisel to take mine out .Some I wanted to save some I didn't so use accordingly. If your car is bare and the sills are good it won't move much anyways it's a pretty strong stucture.My car was totally bare and sitting on jack stands on my rotisserie.I had the jack stands across the front frame in front of the torsion bars and on the rear frame infront of the springs.Like mcnoople said beef up your torsion bars when the floor is out you can add bracing inside the frame there and really beef them up and it will be hidden.When I had my floor out I also added outriggers from my subframe connectors to the sills and added a bracket for the seats.I then cut my floor to fit around outriggers and frame connector and set it in and welded around them. Very solid nice looking job but probably a bit over kill for what you want .Don't have any pictures on this computer willl post some up later if I get a chance.

 

[Moparjake]

Thanks for the advice! I should be able to tackle this here in the upcoming weeks.

-Jake