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Author Topic:   helping a lost friend on his rear susp, need sugs.
FityX
Member
posted January 21, 2004 09:20 PM
I am starting to help a friend of mine with his mod. He and a friend had experimented with the rear suspention all year trying all sorts of combinations. They started off by using leafs cut in half and coils and god knows what else. Not sure what they tried after but they had little sucess. They way the car sits now is that it has mono leafs on both sides along with coils and shocks as you would see on a 4 link. It is also equiped with a torque arm. Personall I would go back with the 4 link set up with the torque arm, but should we consider running the mono leaf on the right side and coil on the left. If so, could someone please dicribe how to do this. Thanks.


jasonracin19x
Member
posted January 21, 2004 09:30 PM
sounds like the car was always a monoleaf car, the mono leafs just do the job of a panhard bar, the coils do the job of holding the car up, if you do have the 4 bar mounts you should definatly go to it, will work alot better that monos


FityX
Member
posted January 21, 2004 09:37 PM
So what you are saying is go with one or the other, not to mix setups?


nwdirtmod2
Member
posted January 21, 2004 11:06 PM
I would run the mono leaf set up. They can be more forgiving to a bad set up then a four bar. But if you know how to set up a four bar that would be the way to go because it is more adjustable then a mono leaf. Good luck.

------------------
Keep it sideways!


jasonracin19x
Member
posted January 24, 2004 09:57 PM
im wondering if i understand you right , mixing setups, do you mean mixing mono and 4 bar? if that is the case i dont know if that has ever been tried, i would go with the 4 bar if you could , but if your just starting the mono would be easier to drive to start out with ,,,,,,,,,,


Ego Racing
Member
posted January 26, 2004 02:11 PM
A mono leaf set with coils is not a MIXED set up. I is a very forgiving setup as the leafs are used as the locating links but they can help with the impact of the engine on the contact patch of the tire and store some energy in the spring and release it slowly. Make sure the monos are run parallel to each other, (not narrower at the front like multi leafs) and parrallel with the frame, as far out as possaple on the rearend toward the wheels. Make sure if there are coil sliders and seperate shocks that the pair on each wheel is mounted exactly parallel to each other or they will bind.
The coil and shock mounts should be about 7 inches below the centerline of the rear end housing.
The monoleafs should NOT be holding the weight of the car, that is what the coils are for. The mono's should be under NO preload with the car set at ride height. You should be able to unbolt the leaf and remove it without a jack or lifting the chassis.


KnightRider6
Member
posted January 28, 2004 10:21 AM
Ego, why do you not setup mono's with the front eyes inboard, like on the multi-leaf? What if you run a multi on the left and a mono on the right? What then?


Ego Racing
Member
posted January 28, 2004 02:18 PM

To work properly monoleafs must be mounted straight and parallel to each other and perpendicular to the rearend housing. Mono leafs are used like a track bar and lower link not as a spring. You would not run a lower link angled in to the center would you? The rear links should be straight forward.
Multi leafs are slightly stronger due to the strength of the other leafs. The multi leaf spring is used for locating the rear and to hold the chassis up, where a mono is not used to hold weight only as a locating link and an engine torque dampening device.
the slider on the rear with the mono needs to work in an up and down motion with thw shock, or as close as on as possable. If the spring was turned in on the front the rear starts to work in an arch, With the slider and a shock on different mounts (even if the two are mounted on one point one is in front of the rear and one is in the rear so they are working on different movement axis) there are 3 different motion axis at work which will cause a bind in the suspension.
On the mono/multi setup I have never run it ( multi leafs are usualy heaver than we use in a chassis where we can run coils or mono's) but I would run the mono straight to keep everything from binding, As for the top link that you run on a mono I don't know about using it on a multileaf setup. I would run a lift bar and center the contact point even with the bottom of the springs.
One last thought. To run a mono on the right and a multi on the left would cause the right side to shorten on application on power causing the rear to steer to the left to the bottom of the corner, you want the car to rear steer to the right to help the car through the corner. A rear to the left would be tight everywere on the track and be VERY hard to turn into the corner, It would push hard.


FityX
Member
posted January 28, 2004 05:55 PM
Ego, correct me if im wrong, but after reading what you wrote, that the mono leafs should not have any weight being applied to them when the car is sitting at rest, does this meant that the car should be set up (shocks and springs) like a regular coil car, or do you have to go lighter on the account of the mono leafs? I think that is the longest sentence I have ever written!

Thanks for the help.

Ego Racing
Member
posted January 29, 2004 05:45 AM
Yes you should set it up so the ciols hold the weight. We generaly get mono's at about 40 - 50 lbs of spring rate and run a 175 left and 150 right coil to start. The coils are a little lighter because the instant the chassis is compressed you gain some rate off of the leaf. The lighter the spring you can use the better and smother the chassis reacts to the spring input. As for shocks we start with 94's on both sides and adjust the chassis with them from there.


jasonracin19x
Member
posted January 30, 2004 06:07 PM
ego, are you sure about the monos being mounted paralell ? i had a dirt works with monos and they were not mounted paralell , they were wider on the back of the spring, it is a forgiving setup just not the fastest....


Ego Racing
Member
posted January 31, 2004 05:32 AM
YES I have checked several areas for this because I didn't want to have to change a bunch of stuff on a LLM that I had. Everyone (spring Mfg's) said the same thing. That to operate correctly they are supposed to be parallel. They are to be used like a lower link and you never wount the links turned in. The idea is to get the spring base as wide as possable that way you can run softer springs.


zeroracing
Member
posted January 31, 2004 09:40 PM
wider spring base will really help over rougher tracks to.


zeroracing
Member
posted January 31, 2004 09:42 PM
wider spring base will really help over rougher tracks to.


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