Working on step notching my 1940 desoto with the understanding that all 1940 mopars used the same X style frames. I plan on installing airbags to lay the center of the frame on the floor. I noticed some Plynouths, Dodges, and Chryslers laying frame and Im wondering if I would need to modify the frame to raise the clearance of the upper x section of the frame to let the driveshaft clear? Im hoping I dont have to butbit appears most 40’s car Ive seen seem to have a tunnel installed on the floorboard to clear thebtranny or the driveshaft. Anyone done this on an X frame 1940’s mopar? o Sent from my iPhone using The H.A.M.B. mobile app
You won't know until you have everything mocked up and in place. That being said I'm no help since my 40 doesn't have bags. Take a look at this thread his frame is highly modified. https://www.jalopyjournal.com/forum/threads/41-plymouth-coupe-392-hemi-build-thread.463453/
@40desoto ........It's an intriguing problem to solve. However, I have to ask....what is so appealing about 'laying frame' ? Where is the benefit? Ray
I am gonna have to investigate the possibility of it being a theft deterrent, possibly in more ways than one...
Just a matter of taste. This one lays on the frame. Right on that x section The black one is also laying in frame but looks lower because he is not using body mounting bushings. Sent from my iPhone using The H.A.M.B. mobile app
Ive always thought that as well. My cadillac doesnt have an alarm not do the doors look. I cant even imagine getting this on a flatbead in an attempt to steal. Sent from my iPhone using The H.A.M.B. mobile app
The floor pan sits about an inch above the center of the X. The motors and transmissions tend to sit pretty low in the chassis, and then the drive shaft runs about the center of that oval in the center. That probably won't give you enough driveshaft clearance with a one piece driveshaft when the center of the X is laying on the ground. If the driveshaft won't clear the center of the X, you will probably have to increase the depth of the tunnel inside the car as well. If you could add a bearing at the center and install a 2 piece shaft, it might work, but I suspect that rear section of drive shaft is going to be pretty short. It may have some pretty big u joint angles at the rear axle. The frame doesn't have a body on it right now, put the motor & trans you intend to use on their motor & trans mounts, set the X on the floor and do some measuring. Gene
Hardy Spicer, you need to get the operating angles correct. http://spicerparts.com/anglemaster/measuring-angles
Thank You Gene, thats exactly what I ended up doing and it cleara with body laying on frame. Also helps that the transmission sits pretty low. Now to see if Ill need to Tunnel the floorpan. Sent from my iPhone using H.A.M.B.
Ive checked out Farmers old post and noticed the x frame chopped to remove the center where the driveshaft goes and allow to add a crossmember in the middle/rear in order to adapt the top 4 link bars to it. Looks good and seems sturdier, has anyone else modified their X Frame like this?
Ive been doing some research and decided that I will be channeling the body 2 inches. Since all of the body mounting brackets sit on the outside of the frame, I plan on relocating all of them 2 inches lower on the frame and taking 2 inches off of the front radiator support to also drop the front 2 inches over the frame. I already replaced the truck pan to sit about 5 inches higher to fit the rear notch and gas tank under. Since I need to create a tunnel for my transmission and driveshaft, I also decided to replace the entire floor plan. The car's floor, rocker panels, and body bracket mouting areas all look solid and completely rust free. Im considering keeping the area where the mouting bolts holes are on the floor and just raising the floor two inches or replacing the entire floor including the mounting area. Any thoughts? Also considering not using any bushings and either mount the body directly to frame brackets, or bolting the body directly to the frame? I know it's done on early 30's coupes but haven't heard anyone doing so on a 40 or newer car
If you want to lay your frame, far be it from me to judge you. But won’t the sharp edges scuff up your little Willy?
Lowering the body mount brackets on the frame will just cause more problems for the clearance between the frame and the floor pan. There already is probably only an inch of clearance, but if you lower the frame brackets, the body mounts will be farther from the frame brackets because the floor pan will be sitting on top of the frame, but the frame mounting brackets are now still 1" lower then they were originally. If you are thinking about replacing the entire floor, I would simply attach the new floor 2" higher up on the body shell (2" is the number you gave, that number can be pretty much any amount you want, as long as you are consistent with the floor pan, the trunk floor will have to be raised the same amount you raise the floor pan, and the radiator support) and leave the body mounting points as they were. That will effectively lower the body 2" (or what ever number you choose) and still have all the body to frame clearances intact. It may also eliminate the need for a tall trans tunnel, you may even be able to use you still good entire floor pan, just lift it up inside the body shell. Your limiting factor on raising the floor up into the body shell will be the required firewall modifications, the motor to hood clearance, and front tire clearance to allow the tires to turn the car without the tires binding on the fenders. You may also have to build an inner panel at the inside of the doors to connect the bottom of the body to the rocker panels because the bottom edge of the doors also will sit lower along with the other outer body panels. By the way, this process is called channeling the body. The lowering effect is pretty permanent, and if you get carried away, you may not have enough lift in your air bags to make the car drivable. A 2" channel is a lot of drop on the body on a car over the frame. Also, if you channel the body too much, instead of "laying frame" when you air out the bags, you may well be "laying body sheet metal", which won't hold up, or look very good very long. Keep the rubber body mounts. They eliminate a whole lot of vibrations, squeaks, and rattles that can make a finished car unpleasant to drive or ride in. A 1" or 2" rubber spacer with a steel insert as a body mount have a lot more cushioning effect then a flat piece of 1/4" thick or even 1/2" thick rubber does. Gene
Fabricate a frame trans tunnel , looks real easy , weld it in before cutting out center plate....and just build a floor tunnel , raise the floor in the trunk..i would only channel a car on stock suspension....its your call at the end of the day...
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