Infraction Ride height

[parcou]

Drill two holes the same diameter as a 2mm wrench in the A arms just like in this pic, problem instantly solved

For the newbie here, can you explain to me what are the front droop screws & function? I have an Infraction but this is a new term for me. I read a lot about lowering the Infraction by turning the shock screws or I guess doing this...what's correct. Thx

 

[arrma_tigger]

The 'droop' is the lowest point that the arm can travel. When you raise or lower by using shock collars, you are changing how much pressure is on the spring / shock - resulting in a change of pressure on the arm. Again, the 'droop' is the max that the arm will go down.

As applies to the Infraction, I believe most are raising the vehicle and not lowering it. Raising it helps to save the splitter.

 

[Notoriousone]

For the newbie here, can you explain to me what are the front droop screws & function? I have an Infraction but this is a new term for me. I read a lot about lowering the Infraction by turning the shock screws or I guess doing this...what's correct. Thx

Droop screws are used to raise or lower the front or rear of the car to adjust ride height and chassis rake. Usually a combination of adjusting shock preload and droop screws will give you a ideal ride height for what you are trying to do with the car. The further the screws are turned in the lower the front will droop, and vice versa. Same for the rear. I usually adjust preload first until I get the shocks feeling right, then use the screws to adjust ride height, rake, and to make sure one side isn’t higher or lower than the other

 

[fpvmiller]

Droop screws are used to raise or lower the front or rear of the car to adjust ride height and chassis rake. Usually a combination of adjusting shock preload and droop screws will give you a ideal ride height for what you are trying to do with the car. The further the screws are turned in the lower the front will droop, and vice versa. Same for the rear. I usually adjust preload first until I get the shocks feeling right, then use the screws to adjust ride height, rake, and to make sure one side isn’t higher or lower than the other

I'm going to (respectfully) disagree here.

My rc racing days we never, never used droop screws to set ride height. Droop screws (inherent by its name) is meant to set your droop. Your maximum droop actually.

Setting ride height is done with the spring collars on the shock. Setting damping is set with your shock pistons and oil weight.

They are all broken down into their specific functions and should never be used to set something else.

If you want to adjust your ride height higher and find that you can't go any higher, you need to look at your shock and spring length and determine if you need more.

When your vehicle is sitting on its own weight you actually want about 30% of the shock travel compressed when the full weight is on. This allows you rebound and compression travel without bottoming out as well as ride height adjustment.

When setting my droop in rc racing I would hold the arms level with no shocks installed and set my droop screws so that they are about 2-3mm away from the chassis. This allows the arms to articulate downward (droop) when hitting bumps, ruts, uneven sections etc. The droop is also set so that your shocks don't fully extend. Just like bottoming out, your shocks shouldn't fully extend when it is off the ground.

To recap:
Set ride height via shock spring collars or shock mounting position. The angle changes the linearity of the shock/spring.
Set droop (maximum) via the droop screw.
Set damping via the shock piston and oil weight.
Set spring rate based on your corner weight.

I have made custom coilovers for my full size vehicles and the spring rate is always based on corner weight. The shock length and compression translates as well. When the vehicle is sitting 25/35% of the shock should be compressed when sitting at ride height. To set my ride height I adjust the spring perches on the coilovers.

 

[BashingBrian]

@fpvmiller ... Great explanation..???

 

[parcou]

Thanks @arrma_tigger @Notoriousone & @fpvmiller

fpvmiller wish you were closer I am working on a coil-over project for my real car but hard to find someone knowledgable for custom suspension work....Nice on both!

This was a good read. I like the Hoons and not the skinny sideways for the S7. I asked if I ever decided to lower my Infraction but the ride height at factory is fine...I'm old school I hate fender gap... If I do bring it down a tiny bit I will work the shock collar but that's a maybe. When I run my rig I try to find the newest, smoothest asphalt parking lots for my rig. When it comes to lowering cars RC or real, I never liked the look of skinny rubber tires on rims added wit the fender gap, but more so you a nice low profile tire with some sideway meat but the chassis of the car with coil overs lowered down to the tires for a nice look. Gives more life to the rims for potholes, more tire to absorb road hazards, and just a better overall look. With the Infraction and Hoons "if" I lowered it a bit, it would be the same look as I do with my real cars.

You all rock....thanks for the knowledge!!

 

[LibertyMKiii]

I'm going to (respectfully) disagree here.

My rc racing days we never, never used droop screws to set ride height. Droop screws (inherent by its name) is meant to set your droop. Your maximum droop actually.

Setting ride height is done with the spring collars on the shock. Setting damping is set with your shock pistons and oil weight.

They are all broken down into their specific functions and should never be used to set something else.

If you want to adjust your ride height higher and find that you can't go any higher, you need to look at your shock and spring length and determine if you need more.

When your vehicle is sitting on its own weight you actually want about 30% of the shock travel compressed when the full weight is on. This allows you rebound and compression travel without bottoming out as well as ride height adjustment.

When setting my droop in rc racing I would hold the arms level with no shocks installed and set my droop screws so that they are about 2-3mm away from the chassis. This allows the arms to articulate downward (droop) when hitting bumps, ruts, uneven sections etc. The droop is also set so that your shocks don't fully extend. Just like bottoming out, your shocks shouldn't fully extend when it is off the ground.

To recap:
Set ride height via shock spring collars or shock mounting position. The angle changes the linearity of the shock/spring.
Set droop (maximum) via the droop screw.
Set damping via the shock piston and oil weight.
Set spring rate based on your corner weight.

I have made custom coilovers for my full size vehicles and the spring rate is always based on corner weight. The shock length and compression translates as well. When the vehicle is sitting 25/35% of the shock should be compressed when sitting at ride height. To set my ride height I adjust the spring perches on the coilovers.

I agree with this having done many track days and drifting motor sports for years.

With that said when doing speedruns on an RC we want the spring as tight as possible with the collar and low ride height, so we use the droop screws to lower the car and keep the spring tight. I install longer droop screws to get the car really low.

If I was to lower the car with just moving the position on the tower or reducing the collar position, then my springs would be too "soft" for this application. Using the limitless infraction springs which are very stiff my car already compresses the spring at 120+ speed and the body scrapes (due to aerodynamic downforce). I think I will try getting a set of rear springs and fit them on the front.

It is mostly just a band-aid fix of a solution as what you mentioned is correct and would retain proper dampening for bumps.

 

[Notoriousone]

Nice explanation, great answer to the OPs question. I’m no expert but it seems like your describing more of a racing setup, I was talking from a RC speedrun point of view as I thought that’s what the question was about



I'm going to (respectfully) disagree here.

My rc racing days we never, never used droop screws to set ride height. Droop screws (inherent by its name) is meant to set your droop. Your maximum droop actually.

Setting ride height is done with the spring collars on the shock. Setting damping is set with your shock pistons and oil weight.

They are all broken down into their specific functions and should never be used to set something else.

If you want to adjust your ride height higher and find that you can't go any higher, you need to look at your shock and spring length and determine if you need more.

When your vehicle is sitting on its own weight you actually want about 30% of the shock travel compressed when the full weight is on. This allows you rebound and compression travel without bottoming out as well as ride height adjustment.

When setting my droop in rc racing I would hold the arms level with no shocks installed and set my droop screws so that they are about 2-3mm away from the chassis. This allows the arms to articulate downward (droop) when hitting bumps, ruts, uneven sections etc. The droop is also set so that your shocks don't fully extend. Just like bottoming out, your shocks shouldn't fully extend when it is off the ground.

To recap:
Set ride height via shock spring collars or shock mounting position. The angle changes the linearity of the shock/spring.
Set droop (maximum) via the droop screw.
Set damping via the shock piston and oil weight.
Set spring rate based on your corner weight.

I have made custom coilovers for my full size vehicles and the spring rate is always based on corner weight. The shock length and compression translates as well. When the vehicle is sitting 25/35% of the shock should be compressed when sitting at ride height. To set my ride height I adjust the spring perches on the coilovers.

I agree with this having done many track days and drifting motor sports for years.

With that said when doing speedruns on an RC we want the spring as tight as possible with the collar and low ride height, so we use the droop screws to lower the car and keep the spring tight. I install longer droop screws to get the car really low.

If I was to lower the car with just moving the position on the tower or reducing the collar position, then my springs would be too "soft" for this application. Using the limitless infraction springs which are very stiff my car already compresses the spring at 120+ speed and the body scrapes (due to aerodynamic downforce). I think I will try getting a set of rear springs and fit them on the front.

It is mostly just a band-aid fix of a solution as what you mentioned is correct and would retain proper dampening for bumps.

Great explanation LibertyMKiii. I’m certainly no expert but for speedruns spring preload adjustment only isn’t enough, you use the droop screws to get the front where you want it, once set they function as a travel limiter

 

[fpvmiller]

@LibertyMKiii @Notoriousone

You both are correct in regard to speedrunning. For general suspension tuning (bashing or racing) what I said is highly applicable.

For speedrunners, at higher speeds the downforce will press the vehicle closer to the pavement. We are getting more into full size suspension behavior but it still translates.

The more downforce at speed you have the more pressure on the vehicle and in turn it will actually drop in ride height. What you want is stiffer suspension (like many speedrunner experts will say) to compensate for the downforce at high speeds.

If your spring rate and damping are tuned correctly then the downforce at speed should be enough to push the vehicle down without the vehicle dropping ride height.

This is why the stiff suspension in racing is misunderstood. The suspension is not stiff because it handles better. The suspension is stiff to keep the ride height constant at high speeds where downforce becomes greater.

I hope that all made sense. This is all translated from my full size coil-over adventures for auto-x. It's amazing how much you have to learn for a set of coil-overs only to find you still only know so little