Installing a frankland Q/C. rear, seems the hangers will hit my buick backing plates unless I have a narrower model A main leaf made.My question is a model T rear spring narrower than an A ?
Don't know the length of a T spring, but the shackle to shackle distance for a stock Model A (these are center of shackle mt to center of shackle mt) is 49-1/4". I have a Halibrand and had to move my shackles in towards the center of the housing 1" on each side to clear my Wilson Welding backing plates on Buick drums. I had to have a new main leaf made..............................
The shackel to shackle length can vary based on how you spread the leaves apart. The width of the spring leaves and the spring pocket in the crossmember differs T to A, the T is narrower, stock T rear is 2 inches, so a T in an A crossmember needs shims to center it in the pocket.
I thought the spring perches on a Model A rear axle were 48.5" apart center of eye to center of eye. Posies makes a spring that fits perches that are 46.5" apart. And Speedway sells a narrower spring as well. The Posies spring has a silghtly different shape that gives a quick change more clearance.
Thanks guys, I did buy a speedway spring,didn't compare it to my original yet. A chopped,did you get the skeleton backing plates? Was wondering about the T spring because that's what the rolling bones use to help lower there builds,I don't want to c-notch the frame.
racemad55, Bib Overalls, the stock Model A shackle dimension eye to eye is 49.125 to 49.225.....always has been at least on 30/31 A's. Since I am running 45 fin Buick drums front and rear I actually bought Wilson Welding's aluminum backing plates. Give me more information on the frame........mine was z'd in the rear 3" for more a nostalgic look. My Halibrand is 60" wheel mounting surface to wheel mounting surface. I also took the top three leafs out............cut them in half and placed them under the spring so I could use the stock U bolts and hardware. (If you didn't do this the spring would be recessed into the crossmember for the U bolts and hardware to keep the spring seated.) The T spring is 2" wide and the A spring 2-1/4" wide. You certainly don't want the spring moving around inside the crossmember. Here are two pictures, one showing the Coupe unloaded (in black primer) and one with a loaded chassis (bare metal with a yellow strip on the door), I don't have to worry about notching the frame because my crossmember is 3" further up than stock. Let me know how I can help.
You can set your perch hangers c/c for 20 -27 T at 48". All Model A's are like Chopped said. Aside from width, you may have suspension issues if you went with a T spring. Ask Pyschobillyboi, he ran a T spring on his roadster. Posies makes a narrow perch version of their Model A spring. Call and check for the setup measurements; at the very least you'll have a ballpark figure to work from.