Bob I have managed to get at the springs I have 3 2 are the same ie 61/2" long i/d of 1 1/10 and o/d of 2 5/16 now these 2 I am sure came off an early car with rubber buffers instead of rebound springs.The 3rd spring is 6 1/8 in length with same i/d and o/d as the others.The one rebound spring I have is 2 5/8 long with an i/d of 1 3/16 and an o/d of 1 9/16. I can not believe that the standard engine is heavier,this climax is not the lighter fire pump one,but very very heavy,if you want to see the springs i live in west worcestershire,hope the above helps regards duncan