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Air Ride Suspensions \ 4-link tried to kill me4-link tried to kill me
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grip
+1y
Originally posted by Russ-D
Originally posted by grip
Most people just can't figure out how to remove the flaws from a reverse and in turn talk down about what they do not understand........
No, I disagree. I think the real problem is that people with reverse 4 links say out loud that "it worked for me" and people, armed with that statement, try to half ass one into their ride. Reverse 4's were born out of neccessity, not proper design, exploer and caprice owners who dont want to lose their rear seating and truck owners who dont want to move their gas tanks.
fact #1: reverse 4 links work backwards in braking and acceleration. This is not me putting down something I dont understand, this is supported by any number of suspension design, physics and math books containing the "right hand rule of torque"
fact #2: reverse 4 links work in an opposite arc to the arc of the driveshaft, causing them to ether seperate or bind in nornal operation unless you limit lift/drop.
fact #3: reverse 4 links apply very large forces to the end of the chassis AWAY from the center of gravity instead of close to it like forward 4 links. This makes them prone to roll steer as BioMAx points out.
This tacoma owner is still steadfast on using his reverse 4 because he doesnt want to move his gas tank, not realizing that if he had installed it forward in the first place it would have 1) only taken about 10% more time to relocate the gas tank and 2) already be driving down the road safely. In addition, Dave (avtek) has shown you can install a very nice forward wishbone 3 link on a tacoma and not move the tank.
The people down on reverse setups quote physics and fact, the people up on them only say "it worked for me", which does more harm than good.
reverse was born out of lack for something better.Reverse does put strain on the back of the frame.Under normal conditions I won't do it but I built my frame and everything around it aiming toward this setup.Can it be done without adverse affects?Yes it can and if you would like to drive my wagon you are more than welcome to see for your self.I don't think your average person should do this but there are a few people that can.People come on here and say a reverse can never work right.I disagree and feel they don't know what they are talking about...
Originally posted by grip
Most people just can't figure out how to remove the flaws from a reverse and in turn talk down about what they do not understand........
No, I disagree. I think the real problem is that people with reverse 4 links say out loud that "it worked for me" and people, armed with that statement, try to half ass one into their ride. Reverse 4's were born out of neccessity, not proper design, exploer and caprice owners who dont want to lose their rear seating and truck owners who dont want to move their gas tanks.
fact #1: reverse 4 links work backwards in braking and acceleration. This is not me putting down something I dont understand, this is supported by any number of suspension design, physics and math books containing the "right hand rule of torque"
fact #2: reverse 4 links work in an opposite arc to the arc of the driveshaft, causing them to ether seperate or bind in nornal operation unless you limit lift/drop.
fact #3: reverse 4 links apply very large forces to the end of the chassis AWAY from the center of gravity instead of close to it like forward 4 links. This makes them prone to roll steer as BioMAx points out.
This tacoma owner is still steadfast on using his reverse 4 because he doesnt want to move his gas tank, not realizing that if he had installed it forward in the first place it would have 1) only taken about 10% more time to relocate the gas tank and 2) already be driving down the road safely. In addition, Dave (avtek) has shown you can install a very nice forward wishbone 3 link on a tacoma and not move the tank.
The people down on reverse setups quote physics and fact, the people up on them only say "it worked for me", which does more harm than good.
reverse was born out of lack for something better.Reverse does put strain on the back of the frame.Under normal conditions I won't do it but I built my frame and everything around it aiming toward this setup.Can it be done without adverse affects?Yes it can and if you would like to drive my wagon you are more than welcome to see for your self.I don't think your average person should do this but there are a few people that can.People come on here and say a reverse can never work right.I disagree and feel they don't know what they are talking about...
purplekush
+1y
Originally posted by BioMax
"and alot of them use reverse 4 links too so the reverse fourlink cant be all that bad if you can jump 30 feet in the air doin 150 and land flat bottom and be fine"
NOBODY reverse 4-links off road trucks (at least none that work.) What you are confusing as a 4-link are called mesanine arms. Much like the S-10 systems with the rearward facing link arms for the bags. A reverse 4-link does not work for any kind of performance. PERIOD!
They will hold the truck off the ground and they will ride decent. They can be done sucessfully. But, never for performance.
I think what is mostly wrong with the suspension on this truck is called "roll steer." Reverse 4-links roll under steer. What that means is that if you were to turn left the rearend is trying to turn the vehicle right. Shocks help, but only cover the issue. The bars need to be moved further to the outside of the vehicle. The narrower the bars the worse the effect. Also the bars should be (from a side view) fairly parallel to the ground at ride height. I would be willing to bet that they point down at the ground, toward the front, at ride height.
It can't really be easily salvaged. Sorry.
no im telling you... there is a ford f150 TROPHY TRUCK that has a reverse 4 link they are modified giant motorsports trailing arms ran backwards . it DOES perform.. it ran the baja 1000 in like 16 something hours wich is average for a trophy truck i took pictures of it myself
not tryin to be a dick or argue but it DOES work
"and alot of them use reverse 4 links too so the reverse fourlink cant be all that bad if you can jump 30 feet in the air doin 150 and land flat bottom and be fine"
NOBODY reverse 4-links off road trucks (at least none that work.) What you are confusing as a 4-link are called mesanine arms. Much like the S-10 systems with the rearward facing link arms for the bags. A reverse 4-link does not work for any kind of performance. PERIOD!
They will hold the truck off the ground and they will ride decent. They can be done sucessfully. But, never for performance.
I think what is mostly wrong with the suspension on this truck is called "roll steer." Reverse 4-links roll under steer. What that means is that if you were to turn left the rearend is trying to turn the vehicle right. Shocks help, but only cover the issue. The bars need to be moved further to the outside of the vehicle. The narrower the bars the worse the effect. Also the bars should be (from a side view) fairly parallel to the ground at ride height. I would be willing to bet that they point down at the ground, toward the front, at ride height.
It can't really be easily salvaged. Sorry.
no im telling you... there is a ford f150 TROPHY TRUCK that has a reverse 4 link they are modified giant motorsports trailing arms ran backwards . it DOES perform.. it ran the baja 1000 in like 16 something hours wich is average for a trophy truck i took pictures of it myself
not tryin to be a dick or argue but it DOES work
BioMax
+1y
FarBeyondDriven:
I'm not trying to be a dick either, but nobody in the suspension engineering comunity would agree that a reverse 4-link will perform.
A reverse 4-link will hold the car off the ground, but it will not transfer the energy that the rear end creates while it's driveing (braking or accelerating) to chassis in a useful manor.
If the trucks "works," then we all need to redefine the term "works."
I'm sorry I am being very asshole, but this is not something I "think" is right...
...As I wrote in another forum, go to www.eng-tips.com and ask those guys what they think about reverse 4-links. Not one will say that they work. This is where I go when I need a question answered.
I'm not trying to be a dick either, but nobody in the suspension engineering comunity would agree that a reverse 4-link will perform.
A reverse 4-link will hold the car off the ground, but it will not transfer the energy that the rear end creates while it's driveing (braking or accelerating) to chassis in a useful manor.
If the trucks "works," then we all need to redefine the term "works."
I'm sorry I am being very asshole, but this is not something I "think" is right...
...As I wrote in another forum, go to www.eng-tips.com and ask those guys what they think about reverse 4-links. Not one will say that they work. This is where I go when I need a question answered.
dssur
+1y
Originally posted by FarBeyondDriven
no im telling you... there is a ford f150 TROPHY TRUCK that has a reverse 4 link they are modified giant motorsports trailing arms ran backwards . it DOES perform.. it ran the baja 1000 in like 16 something hours wich is average for a trophy truck i took pictures of it myself
not tryin to be a dick or argue but it DOES work
No, you dont know what you are talking about. What you are describing is exactly what BioMax called a mezzanine setup, they are also called nezzy links and sometimes called cantilever setups. They STILL HAVE FORWARD LINKS which control movement of the rear end and the upper bars are cantilevered over the axle and used for support thusly.
and in practice it looks like this
and this kind of proves my point, people who DONT know what they are talking about get into discussions with people who DO and other people take their WRONG advice.
Not a reverse four link on a trophy truck, because that would be pure and abject stupidity.
no im telling you... there is a ford f150 TROPHY TRUCK that has a reverse 4 link they are modified giant motorsports trailing arms ran backwards . it DOES perform.. it ran the baja 1000 in like 16 something hours wich is average for a trophy truck i took pictures of it myself
not tryin to be a dick or argue but it DOES work
No, you dont know what you are talking about. What you are describing is exactly what BioMax called a mezzanine setup, they are also called nezzy links and sometimes called cantilever setups. They STILL HAVE FORWARD LINKS which control movement of the rear end and the upper bars are cantilevered over the axle and used for support thusly.
and in practice it looks like this
and this kind of proves my point, people who DONT know what they are talking about get into discussions with people who DO and other people take their WRONG advice.
Not a reverse four link on a trophy truck, because that would be pure and abject stupidity.
balcar
+1y
In that pic of that truck jumping, is that a broken shock in the rear fenderwell? What a POS!, LOL j/k.
And yes, reverse 4-links are poooooo
And yes, reverse 4-links are poooooo
dssur
+1y
Originally posted by grip
pulling is an equal force to pushing as long as your frame is strong enough.
thats only one axis though. the physical world exists in three axes, and the reverse link fails in the other two.
If I laid a big heavy I beam on the ground and told you to rotate it about its center, would you push at the center? no, the beam would likely move sideways and not rotate. You would probably push at the end, furthest away from the center of gravity, and the beam would rotate easily. Move closer and closer to the center of the beam while you are rotating. Is it needing more or less force to rotate? Now picture the beam as your frame and the rotating around the center of gravity as oversteer. which link system would encourage it?
Hammer a nail into a board so it sticks out about a 1/2 inch. Now take a paint roller and hold it at about a 30degree trailing angle and pull it along the board over the nail. The roller will pop up and over the nail no problem, and you will barely even feel it in your wrist. Now take the roller and hold it at a 30 degree leading angle and push it along the board. When it gets to the nail it will tranfer almost all the engergy of hitting the nail back along the handle to your wrist. decrease the angle to only a few degrees, so your handle is barely over the board, and repeat the test. Now is there a difference between push and pull?
And BioMax has covered the accel and braking problems.
Originally posted by havok
In that pic of that truck jumping, is that a broken shock in the rear fenderwell?
No, those trucks use hydraulic bump stops for infinitely adjustable compression. Thats likely the bottom of the hydraulic ram you see.
pulling is an equal force to pushing as long as your frame is strong enough.
thats only one axis though. the physical world exists in three axes, and the reverse link fails in the other two.
If I laid a big heavy I beam on the ground and told you to rotate it about its center, would you push at the center? no, the beam would likely move sideways and not rotate. You would probably push at the end, furthest away from the center of gravity, and the beam would rotate easily. Move closer and closer to the center of the beam while you are rotating. Is it needing more or less force to rotate? Now picture the beam as your frame and the rotating around the center of gravity as oversteer. which link system would encourage it?
Hammer a nail into a board so it sticks out about a 1/2 inch. Now take a paint roller and hold it at about a 30degree trailing angle and pull it along the board over the nail. The roller will pop up and over the nail no problem, and you will barely even feel it in your wrist. Now take the roller and hold it at a 30 degree leading angle and push it along the board. When it gets to the nail it will tranfer almost all the engergy of hitting the nail back along the handle to your wrist. decrease the angle to only a few degrees, so your handle is barely over the board, and repeat the test. Now is there a difference between push and pull?
And BioMax has covered the accel and braking problems.
Originally posted by havok
In that pic of that truck jumping, is that a broken shock in the rear fenderwell?
No, those trucks use hydraulic bump stops for infinitely adjustable compression. Thats likely the bottom of the hydraulic ram you see.