Finally got the 347 up and running in the Comet, next step is the saggy rear suspension. I am also ordering subframe connectors from chassis engineering. I've been looking through old threads and couldn't seem to find a definitive answer on leaf springs (3 vs 4 and spring rates), I'm also wondering whether or not the difference between single and double adjustable shocks justifies the price? The car will be mostly street driven with some auto x in the future.
You'll get different opinions. I've replaced leafsprings 3 times in my '73. First time was 4-leaf from JC Whitney. Decided they were too stiff. Replaced them with 3-leaf from ESPO. Car sat too high. Replaced again with 3-leaf (also from ESPO) with 1-inch drop. Still rides pretty stiff. I even got rid of the polyurethane bushings and installed new rubber. Shocks are KYB twin-tube...
With stock leafs I installed polyurethane bushings and competition engineering slapper bars with air shocks my car went 1.48 60" very consistently.
I used 4 leafs which cured the sagging rear but as TeeEl stated, the ride is a little stiff. Not sure of the spring rate or even what brand they are. Bought them from the now defunct Laurel Mountain Mustang. Probably the same ones that J.C. Whitney carried. I am ok with the ride height now and even though the ride is a bit stiff, I like the handling improvement. Also added Addco rear sway bar with KYB shocks.
