I have the front seat cushion spring for my 1915 roadster, but I am missing the backrest spring unit. I am considering replacing the missing backrest spring unit with foam rubber. Does anyone know the dimensions of the back rest spring unit? Would this be a good alternative to purchasing a new spring unit (it would be cheaper)?
If you are unusually tall, it would give you more leg room, but would not be as comfortable as springs. You can get the springs from the vendors.
These people make the springs and can answer all your questions
if you use foam make sure you use super foam firm.get it from an auto upholstery supply store. you can get it 7" think and the big stores will cut it in a tapper for you.charley