ladder bar with floating leaf spring set up
 

i have a 72 z28 with a 12 bolt and ladder bars. the car was as is when i got it and my 60' times are at 1.48 and should be 1.35 or so. everyone is saying that the rear end must be binding up and not moving like it should? Just need some help understanding how to tell whats causing the problem .......thanks

Need more info about your setup? You may be running good 60" times for your combination. :)

the motor made 759 hp on dyno, running automatic w/4500 stall and a brake. car picks up the front tires about 6-8 inches and then they drop and tires spin some. what info would help?? Thanks !

The only experience I have with floating leafs is on dirt ovals. Although I did have a brainstorming session with a guy about just such a deal in the 70s. Binding was one of the concerns we discussed. There probably be no bind in the rear half of the spring due to shackle or slider. The front half is where you could get some binding. If there is some arch that could eliminate some of it, how ever any bind would come from the difference in ark between the front half of the ladder bar and the length of the front half. If you had a shackle or slider on both ends of the spring, It should have no bind or stiffening of rate at the farther reaches of travel. If the ladder bar and the front spring mounting hole are the same length and parallel you would have no bind.

Just a by the way deal. the leaf spring floating was used on the right side and it was not floating on the left side, on the dirt oval. With the aid of a well arched left spring and a spring/ coil snubber it induces rear steer to aid in corners. Some Modifieds are still using a similar set up. The left spring lengthen or shortens wheel base on that side and the snubber decides how much.

I have an F body (see avatar image) and had the same setup, low 1.40's was it. Best thing I did was cut the leafs out and go to coil overs. Then I started seeing some mid 1.30's in good air and track conditions:wink:

So, let's try these for starters, tire size, gear ratio, car weight, converter stall on brake with no chip. what kind of automatic PG / 400 / 350 etc...?

imo get rid of the leafs & go to coilovers it will help you a ton.good luck