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Author Topic:   Anyone here have a few tricks for leaf springs
nw15x
Dirt Full Roller

Total posts: 42
posted December 03, 2002 09:07 PM
I use standard leaf setup on a camaro. Does anyone have any experience with sliders. Also I have heard you can setup your rear spring mounts so they can be adjusted as weight jacks. any info on this would be greatly appreciated.......thanks

racnfool
Dirt Full Roller

Total posts: 38
posted December 04, 2002 09:30 AM
Run a leaf spring floater on the right side and a heavy dampner shock on the upper rear end to chassis. Get 58% rear weight, I prefer to fill the frame or tubing with molten lead or lead shotgun shot. (This will keep it from being noticed by the competitors as you start winning) You may need to remove the grease zerk from the spring floater before going to the track to not draw attention to it. Most rules do not specifically rule them out, but it is only an advantage if you keep your mouth shut. I have had many people look at the setup and never even notice. The setup will promote left rear bite under acceleration thus you can jump off the corner a ton faster, especially on dry slick. A weight jack on top of your spring sliders will help tremendously on setup. I used 1.5 sq tube with 1.25 inside of it to let the slider box adjust with a weight jack bolt. (PM Me if you want , I have a couple I would sell if you dont want to fab your own) AN Adjustable lowering block on the right will help keep ride height equal and you can keep the rearend squared. Also 50-53% left will be sufficiant to start with also 49-51% crossweight. Adjust to your preference from there. Do not be overly concerned with TOTAL WEIGHT!!! Just get the percentages as close as possible. Use plenty of rear gear and HP

66jj
Dirt Freak

Total posts: 352
posted December 04, 2002 03:41 PM
sliders are the best...

90-10 shock on top.


75xracer
Dirt Full Roller

Total posts: 40
posted December 05, 2002 10:45 AM
racnfool- Your settup has me thinking about trying it. How long do your springs last? When you say heavy damper shock- 90-10, right? Here's my idea for a settup. Everyone let me know what you think. Car is a 3200lb camaro running a medium banked 1/4 mile. springs: 900lf, 1000rf, 200 landrum lr, 200 landrum rr, (floating). I'm also thinking of trying another trick by sliding the second longest leaf forward on the lr leaf, and redrilling the centering hole. Plenty of wedge, maybe 100-150 lbs, 54% rear, 52% left. Think it would hook? Too tight? Just a theoretical starting settup, but I might try it. My theory is based on what late models and modifieds have gone to, which is alot of body roll,and alot of bite at the lr. I know it won't work as well with leafs, i'm just thinking out loud.

c21
Dirt Freak

Total posts: 346
posted December 05, 2002 11:11 AM
have given some thought to this myself 75xracer,

I'm thinking 200 on LR (with this set-up)may be too soft and ...you should slide ALL of the blades forward and possily add 1 (forward only)to left rear. Have some good bits on hand, I've gone through more than a few drilling springs.

c21

RC Racing
Dirt Maniac

Total posts: 144
posted December 05, 2002 01:12 PM
75xracer: I'm driving a smiliar car, an early 70s Malibu full-framed car, 3200#s, similar front spring rates (weights?).When I bought the car, it had matching (2 AFCO 20228s)multi-leafs on rear.
I raced it a same track where previous owner raced it. I experienced bad push. As soon as I changed LR leaf to heavier rate (AFCO 20228HD on L, 20228 on R), no push, won heat race 1st time out.

Curious as to what's the reasoning behind moving leaf (assuming y'all are running multi-leafs) forward? What's the proper method for doing this? How far forward? etc etc

75xracer
Dirt Full Roller

Total posts: 40
posted December 05, 2002 03:06 PM
Yea, it probably would be a good idea to stiffen the lr. RC- The way I look at it, if you stiffen the front of the spring,(by sliding leafs forward) it will act like a slapper bar, and plant the lr under acceleration. I don't know of a proper proceedure, like I say, I'm just thinking out loud. Keep em coming, pros and cons.

DMS CEO
Dirt Freak

Total posts: 212
posted December 05, 2002 04:57 PM
#1-Lets get this outof the way. AFCOS suck. I bought five sets of the same rate because I was suspicious of their quality. Out of five sets the ride height was different on all five,a TWO inch swing, I dont know about you but I dont want to have to worry about new parts being good or not. I can feel my springs losing rate or hook and I may have to change at the track and it is hard to find level ground at the track. Dont run sliders run shackles they are cheaper and way less maintenance. Dont out think yourself on this leaf spring deal.

Lazy R
Dirt Roller

Total posts: 17
posted December 05, 2002 05:37 PM
Makes me wonder if a leaf spring car is the way to go! I've heard a lot about leaf springs losing their rate and constantly keeping the weight off of them. I haven't deciced which way to go yet.

Dirt01
Dirt Roller

Total posts: 17
posted December 06, 2002 12:04 AM
Will a 90/10 shock (dampener) really help on a leaf spring car? Couldn't you achieve the same thing by adding a leaf or 2 to the left side? We're having a discussion with the tech guy about allowing a 90/10. He thinks it really won't help on a leaf car. You see, the new rules say "ONLY 4 shocks per car and no torque absorbing devices" Thanks

75xracer
Dirt Full Roller

Total posts: 40
posted December 06, 2002 08:52 AM
DMS- Afco's may suck, But I've won my share of races with them. You are right though, they are not consistant from one spring to the next. Three years ago I ran a limited late model with them and won ten races that season. The thing about leafs that alot of people forget is that they don't last long. we replaced them every 4 races, and every time we replaced them, we would be a little faster and more consistant than the previous week. A friend asked me what was wrong with his car, which was winning the previous year, but had slowly drop to the back of the pack, and wouldn't hook. (Same springs he had on the year before) I told him to simply replace them. He won his heat and feature that week. I like afcos, but I would think that Landrums would be good too, since that's all they sell is springs, I just haven't run them enough to compare. I have to disagree on the sliders. I like them, and greasing them once a week is not too much maintenance for me. Dirt01- The main purpose of the 90-10 is to dampen the top of axle's forward movment when you hit the brakes. Have you ever had a rear tire hop under heavy braking? A 90-10 will help that. It won't help forward bite, but it will probably make your springs last longer. About moving the leaves forward- if you added leaves, you would stiffen the whole spring. The idea of moving leaves forward (the way I see it) is to stiffen just the front, while keeping the same overall spring rate. I'm no expert by any means. Like I say, I'm just thinking out loud. LazyR- If I had the choice between stock coil suspension and leaf suspension, I'd choose leaf, but that's just because I have more experience with a leaf setup than coil. If your rules allow you to run a more adjustable coil suspension, you'd be better off going that route. (imo)

racnfool
Dirt Full Roller

Total posts: 38
posted December 06, 2002 01:19 PM
If you run a spring floater on the right you will have more left side hook up under acceleration. I prefer a good heavy 50/50 shock for the top damper with the floated spring. It actually does absorb torque and help the rear to load the wheels under acceleration. Don't tell the tech guys everything! I may have a couple more sets of slider jack setups available, let me know if your looking.

75xracer
Dirt Full Roller

Total posts: 40
posted December 06, 2002 01:58 PM
Racnfool- I think I see what you mean with a 50/50 shock, but I would think that you would want as little resistance as possible for rearend to twist backward, thus creating lift on the front of the spring, and planting the rearend. Did that make any sense? Why not let the spring absorb the torque?

nw15x
Dirt Full Roller

Total posts: 42
posted December 06, 2002 07:28 PM
who makes a leaf spring floater any where on the web i can see what you are talking about

outlawstock17
Dirt Forum Champ
Total posts: 620
posted December 06, 2002 07:38 PM
i believe what you're refering to is a housing floater. competition engineering makes them for drag racers using ladder bars with leaf springs. they're available at summit for $96.00 a pair.

[This message has been edited by outlawstock17 (edited December 06, 2002).]

nw15x
Dirt Full Roller

Total posts: 42
posted December 06, 2002 08:18 PM
these look pretty big how do you get them past tech

c21
Dirt Freak

Total posts: 346
posted December 09, 2002 10:39 AM
you can make your own leaf spring float-mount by resizing a clamp-on style mount on a connecting rod resizing machine.

c21

75xracer
Dirt Full Roller

Total posts: 40
posted December 09, 2002 11:42 AM
Good idea, c21. I've been trying to figure out how to stop the side to side movement without it being obvious that it's floating. Any ideas?

c21
Dirt Freak

Total posts: 346
posted December 09, 2002 12:04 PM
You could try a clamp-on shock mount on the right and then monitor motion on the left by looking for paint being scraped off. If you find the spring needs to be located on it's inboard side as well .... weld half a ring out of normal view (from 12:00 to 6:00 in passenger side view).

If you don't like the clamp on shock mount, you could try welding a half ring on both sides of the spring mount, both from 12:00 to 6:00 (in this case, I would radius the leading edge of both of the half-rings on the spring mount side to limit gouging).

Liberally applied black spray-paint over-spray and/or painting everything non-gloss (satin) black and using black grease always help to hide things like this.

c21

c21

racnfool
Dirt Full Roller

Total posts: 38
posted December 10, 2002 01:32 PM
The spring floaters I have used and seen are real simple, round tubing with a nylon bushing and grease zerk,two guides for the u-bolt which makes it appear as a shock mount or stock type bracket. Unless you look very closely you will not notice it is functional. I bought the floater rear end with the spring floater in place. I don't know who makes them or where to get them.

c21
Dirt Freak

Total posts: 346
posted December 10, 2002 03:30 PM
racnfool, it would be cool to see a picture of that.

c21

66jj
Dirt Freak

Total posts: 352
posted December 12, 2002 12:43 AM
I dont get the sliding leafs forward, ive raced with leafs for 8 years. and it was my understanding from landrum, that the front of the leaf is the trailing arm, and the back is the spring, which makes up most movement and has the rating..

moving leafs foreward will stiffen spring wrap up under acceleration and soften the heck out of the spring i would think?????

why not just add a half leaf to the front, to stiffen it on acceleration, if its hopping??

c21
Dirt Freak

Total posts: 346
posted December 12, 2002 10:42 AM
you are correct, however, as shipped the front of the spring is more of a spring and less of a trailing arm than some might like.

sliding leafs forward will soften the rear a little more than it stiffens the front so adding a leaf to the front would seem to be the way to go. I find doing both and/or upping the rate of the base spring to be a good solution.

c21

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