as above,when and why would you use it?

I think I will monitor this thread…I want to see what people have to say.

i used it on my tc5 drifter to try and gain more 'castor'. and for the most part it worked

Hey Guy's,

I think what I does it Give’s the car more Mid corner to exit Steering. ( You Loose a little turn in ) but you can ad anti dive to to bring back the steering into the corner.

That's the way I understand it as well. I think about the direction the weight is moving upon entry and the angle that the suspension moves relative. With sweep the motion is slightly more opposing of that weight transfer. As the car begins to settle that angle may allow the load to transfer from outer front to outer rear giving the car better rotation in the center and likewise when one get's back on the power... the angle opposes weight transfer from outer front to inner rear (too much causes the understeer upon exit). That's just what I see in my head. I'm also interested to read others' takes on this as well.

pin sweep can be used two ways, but the most common set up is positive pin sweep, where the front of the pins aim away from the center of the car. I have seen this on a lot of MOD set ups. Without all the fancy thinking Lessen did above, here is what I think of it as, and how it works. First, I feel it actually helps turn in harder and act as "TOE GAIN" on the inside tire. So lets say straight ahead you have 0 degrees of toe adjusted in, as you turn the car left, due to the angle of the A-Arm the left tire will start gaining positive toe, where the right tire is going to stay neutral or even be a little "behind". I don't think it will change the castor on most cars as that is adjusted with the c-hub, but it will give the feeling of increased castor. IMO

It sounds as if you are explaining the geometry action known as bump steer, except I don't really see how arm sweep has any affect on bump steer. It may however, have a minor effect on ackermann (in an active manner) because the angle of the pin now causes the entire suspension (most notably the steering link pivot at the hub) to move ever so slightly forward as it goes through it's motion. As it moves slightly forward it would be gaining ackermann as it progresses. I think that would be quite minor.

the way i see it is arm sweep is generally moving the end of the arm backwards,this will give less castor,shorten the wheel base,and affect ackerman,so will obviously affect the car in a big way,so why use it if alot of other settings are changed?
this is taken into account when setting up the car,but what i really want to know is what it actually does,and why it does it,is it just a mod thing as i only run 13.5?
if you do use arm sweep would you move the shims around to get back to the original wheelbase and ackerman leaving just the castor with arm sweep changed?

Arm sweep won't effect castor as that's set by the blocks and the 'kick-up' and 'anti-dive' settings of the pivot pins

doh! yeah i just turned blond for a minute,it does move the top link further back,i know its minimal but would that have an effect?

My thinking was it places the wheel base further back shorting wheel base , which puts more weight over front tires affectively softining front suspention which in my theory delays turn in response and gaining mid corner exit . I'm sure it affects Ackerman also (acts as if u added more shims to steering link

Front Arm Sweep:

Front mounts are wider then the rear in the front of the car.

This provides less initial steering, but more mid corner steering.

This ^

The biggest effect that arm sweep achieves is how it creates suspension bind. The more angled a hinge pin is, the more suspension bind you will create as forces work against each other when compressing.

Arm sweep essentially makes the front end stiffer because the hinge pin is essentially angled towards the opposite direction that the outside arm is trying to hinge in compression in a corner.

Like most set-up changes, when stiffening the front end of a car a harder front end will delay weight transfer and create less grip going into a corner. However, as the car starts to turn and lean the increased rate on the tire will create more pressure on the tire essentially creating more traction, hence more middle and exit steering.

I use arm sweep in everything. To me it's a default set up thing. I feel it makes the car easier to drive going into the corner. I am not saying this is the best approach, but most of the time it works. Only if I am looking for more initial reaction will I take it out, however most of the time a little more camber, shock angle change or an adjustment on the inner camber link can get me the reaction I want.

I think I have to disagree on one of Ur points (at this time )
Don't see how adding arm sweep (back) makes suspention stiffer .
It places more weight on front arms /tires thus making it feel like a softer spring .
Example . pushups .. Do pushups 3 different ways . arms strait out from shoulders (normal)
Arms more tward Ur stomack (hard ) ,arms out from Ur head (easy )"girl pushups"lol
This is why i have my idea about sweep