When racing, softer is better......to a point.(old guy is definitely RIGHT) If you seen Stephen Moores video, the last past when he is doing what I call "chasing it"all the way down the track, its because he has a soft set-up....for better bite. Thats what it takes to get BIG POWER to the ground! If your local track has a heads-up street car race, watch them guys going down the track, they are "chasing it" the entire way, especially if they are fast! And I personally think Steve has the best "stock" suspension you can get for these cars(Mavs and Comets)! He truly is getting after it with leaf springs!!!!!!!!!!!!!!! But yes, everyone is right, you must build your car to your specific need. I have coil-over/ladder bars on mine, thats what fit my need. Good luck!
Well....softer is BETTER...after removing the shims I had on the springs, the arch on the springs still looked real good. I put the traction bars on and the wheel well sits about 2 1/2" above the 14x10 tires. As I shower down on it the back end squats so hard the wheel well scraps the right rear tire the traction is being applied on. I think once the 9" inch with posi goes in it will distribute the weight transfer better not allowing the scraping on the tire. Opinions on my theory?
The reason the right rear is 'squatting' more is due to the torque applied to the rear axle by the driveshaft. It's trying to rotate the housing, which actually in a sense tries to lift the right rear (and that's why it looks like it squats harder on that side.) I just pre-loaded that side with a longer home-made shackle at first, then after I made my own cal-trac lookalikes, I just added preload with the right side bar. And no, a posi isn't going to help the right rear squat less. Even full-on spools in drag cars do it.
At this point I think I'll wait till the new rear goes in before doing anything else, that way I get a better idea of what it needs...I don't think it gonna get much better with a stock rear end in it.
I have been told that mine launched launches pretty good. Fairly straight with the wheels slightly off the ground. I am no expert, thats just what I have been told. But I have coil-overs/ladder bars, I would say it would be hard to get rid of the "squat" with leafs springs.
In the stock and super stock drag racing ranks, some of the best launching stock cars are the MOPARs. Blasphemy I know, but still true. If you look at 60's vintage MOPARs running in these classes, you will see leaves that are off center. That is to say that there is more spring towards the front of the axle then behind. This offset makes the spring stiffer in front of the axle and limits spring wrap up. Add spring clamps to the front to hold them straight and remove the clamps from the rear of the springs then add a good set of slapper bars and you have a stock car that can launch with the best of them. A good spring shop can do this to your springs. It will work on any leaf spring car. Just an observation from the starting line.
Thx for all the info guys.... I think my terminology is a little off. When I said squatting....I mean planting...with the 3 leafs and slap bars the weight transfer is much better compared to the old setup. I had the back jacked up too high to get a good plant before. I just need to wait and see what the 9 does for it now. I think it will be good for a street car but if not I'll try Bobs suggestion.
Well, i'll throw my 2cents in here for what it's worth!! For overall streetability I think the leaf spring is probably the best but leaf springs were not designed for an all out drag race launch. The leaf spring is required to do two jobs, locate the rear end and also support the car and act as a spring. For all out drag applications a ladder bar or 4-link will outperform a stock leaf spring setup. Multi leaf springs have an inherent problem in that under a hard launch, axle wrapup causes the leafs to want to seperate which causes body seperation and just doesn't make for a good launch. As stated, a quick fix is to clamp the front half of the spring (as described in Dave Morgan's book Doorslammers: The Chassis Book). A slapper bar actually needs to be adjusted to an individual cars needs, usually by using pinion shims to adjust the angle of the bar as it relates to the spring. The ultimate stock leaf spring setup is running a mono-leaf spring with a nice adjustable traction bar. (Cal Trac/Slide a link/Homemade bars) The cal tracs and others allow you to set preload to help keep the car straight, you can make slight pinion angle adjustments and the cal tracs hit the tire harder and more accurate then a slapper. THe mono leaf design is far superior to the multi leaf and seperation is not a concern with one leaf . ON the street alot of people will back the cal tracs off so the ride is not harsh, although when I was running multi leafs I never backed them off on the street and never had a problem. Also one of the most overlooked items is the shock, a nice adjustable shock is hands down the best way to go. I would suggest that you pick up a copy of Doorslammers and read it, you won't regret it! I"ll attach a picture of my rear setup....
