I have a 31 A coupe that I had planned to lower the rear of the car. There are plenty of discussions and videos of zing the frame or adding new curved frame rails to raise the rear end and lower the frame but there are only a couple of posts about modifying the body to go down over the zeed frame. When I saw that much of the rear of the body rails had had to be cut out so the body would slide down over the frame I do not like this. Someone mentioned that they pinched their frame to achive this. Can anyone tell me what pinching a frame means and how it is done?
When I hear pinched frame I think narrowing the width at the front and cowl area. The only other thing I can think of is they are narrowing the frame height itself. So if the frame is 4" tall they are cutting part of that height away. It's what I call "C'ing" or "notching" the frame. Now if your running a stock a frame, which isn't that stiff to start with, and want to notch it I'd build plenty of support and gussets in the rails at the notch. ....
My 30 coupe has a stepped frame and I trimmed the ends off the rear crossmember, all I had to do was cut a small notch in the sub rails and I boxed it afterwards. Couldn't find a picture of the trunk before I built the raised floor but you can see that most of the rear sub rails are there beside the raised section. If you look closely you can see where the mounting bolts to the crossmember are moved in by the raised section.
Been quite a few years that have p***ed since I helped channel a couple Model A's; but it seems to me if you trim the ends of the rear cross member like Gomez says; then cut the sub-rail cross pieces and trim the inner edge as needed to clear as you go forward, then remove the cowl mount brackets on the side of the rails, and finally trim the front corners to drop over the rails; you will have pretty much channeled your A. Obviously support and brace as you go. Should be a lot easier and cleaner in these modern days of cut off grinders.
Thanks Gomez and Rich for your input. I have dropped the front axel about 4-5" and now want to get the rear down for the wheels to match wells. I was planning a 6" Z similar to Gomez's but another couple inches. Doing the frame work to accomplish this is easy. What is not is, what has to be done to the body sub rails and the cross member in the body subframe that is just in front of the rear frame crossmember. Gomez cut out about half of the subframe rail, cut of the ends of the rear frame crossmember where the body mounts, built a tall box in my case 6 inches and rewelded the pieces cutoff after the body was onto bolt the body too. It seems to me if you could pinch in the frame that 2 to 2 1/2" on each side, you would not have to cut the body subframe at all. Would appreciate more info and pictures from Gomez
The best information I can give you is some measurements, by cutting off the ears on the rear crossmember even with the frame makes it 39 " across. I didn't try to measure the cut on the subrail because it's close under the car, the raised section of the floor is 41 1/2" and I drilled new holes in the crossmember 37 1/2' apart to mount the rear of the body and there is a wood block on top of the crossmember like a stocker. I notched the subrail and boxed where I cut it for strength, The step is the width of the frame which is 3" and the gusset is right behind the cross subrail. I measured the stock rear body mount holes on another frame and they are 40 3/4" apart so the notch in the subrail is about 40" across and you can see the cross subrail in the picture. My coupe is a 50's style hot rod, flathead V8, 41 pickup top loader trans, closed drive line with a transverse spring with a couple of leaves removed. I hope this is enough information to help.
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