What does the upper shock mounts on a chassis do to your shocks?

[lil' lucifer]

Like the title says...

I'm just rying to figure shit out and learn exactly what stuff does. So what do the different upper shock mounts on a chassis do to your shock? What does a shock standing straight up and down do differently than a shock sitting at to a 45* angle?

 

[lil' lucifer]

I'm guessing its harder to compress the shock at a lower angle beacuse of suspension travel.

 

[robsdak]

Like the title says...

I'm just rying to figure shit out and learn exactly what stuff does. So what do the different upper shock mounts on a chassis do to your shock? What does a shock standing straight up and down do differently than a shock sitting at to a 45* angle?

it adjusts your ride height. nothing really, a shock is a shock.

 

[lil' lucifer]

it adjusts your ride height. nothing really, a shock is a shock.

I'M NOT TOO SURE ABOUT THAT! cause if you put a shock in a hole in the chassis that makes the shock almost lay down it hardly even compresses when you cycle the suspension thru.

 

[Manning]

Laying the shock over makes it act softer. More vertical makes it act stiffer. Ride height will change depending on exactly where the holes are. Try it and see, it's not a permanent change.

 

[Harvo]

It's all leverage and shock length. I was running 4" shocks on my rockshow and they were laid back pretty far. I liked that because it made them act really soft. I was able to keep ride height up by adjusting the collars about halfway down the tube, but it didn't make the shock stiff because they were laid back really far.

When the wheelbase rule changed, I had to shorten my shocks a quarter inch. That resulted in me having to stand them up more and adjusting the collar back to make the spring act softer.

If you change your shock angle, you almost have to change your preload or shock lengths or your ride will change pretty drastically in some way.

It's fun to play around with as long as you aren't in a hurry :mrgreen:. You might just find a setup you like better. I did. "thumbsup"

 

[robsdak]

I'M NOT TOO SURE ABOUT THAT! cause if you put a shock in a hole in the chassis that makes the shock almost lay down it hardly even compresses when you cycle the suspension thru.

if you already know , why ask??? on the frame i am running, it doesn't do anything but change the ride height. but you know better than i do.. no i don't run an expensive "comp" chassis, it is a Rock Rider from RC4WD.

and moving shock locations, it changes the ride height and suspension travel IE: before it bottoms out. has not a thing to do with compression of the shock. 2lbs at 90 degrees is 2lbs at 45 degrees..

now changing your pre-load will change the way a shock acts.

let me ask this, in theory, if it change;s things so much. why is there different spring weights? hard , medium, soft?

 

[ultimate_monkey]

if you already know , why ask??? on the frame i am running, it doesn't do anything but change the ride height. but you know better than i do.. no i don't run an expensive "comp" chassis, it is a Rock Rider from RC4WD.

and moving shock locations, it changes the ride height and suspension travel IE: before it bottoms out. has not a thing to do with compression of the shock. 2lbs at 90 degrees is 2lbs at 45 degrees..

now changing your pre-load will change the way a shock acts.

let me ask this, in theory, if it change;s things so much. why is there different spring weights? hard , medium, soft?

L O F-ING L! hate to tell ya but shock angle changes alot, more then just ride hight. it will change thinks like ride high, progression rate, dampaning / rebound rates, amount of suspention travel blah blah blah... dont beleive me?

try this.. (sorry i suck at explaining things), take a loose shock put one end on the ground and hold the other, with the other hand lift the bottom of the shock up (keep the top perfectly still) compress the shock so that the bottom is 1" off the ground, take not of how much pressure ur applying and how much shock travel you have cycled threw. now hold the shock 45* once again hole the top station ary and lift the bottom of the shock one inch, makeing sure you follow a vertical plane, you will use less pressure and the shock will have compressed less


and there is differnt spring rates for fine tuneing, why do u think? a vertical shock with a soft spring will be as stiff as it can get, but what happens if u want somthing stiffer, well u need a stiffer spring obviously

 

[wicked4x4]

so i know the answer to this from crawling and off-roading real jeeps/trucks.

increasing the angle of the shock from a verticle position decreases the efficiency of the shock, but also gives you more travel on the axle.

ex/ if a shock is mounted vertical, it is most effective, but you get the least amount travel.
ex/ if a shock is mounted at 25 degrees off vertical, it will have a bit more travel, but be about 82% as efficient as vertical.
ex/ ...mounted at 45 degrees, it will allow much more travel on the axle, but be about 50% as efficient as vertical.

i cant for the life of me find the calculator i used when mounting my shocks for my jeep. this is the best i could do to give a bit of a chart on this http://stockcarproducts.org/pstech8.htm

 

[wicked4x4]

this link is for an article for mounting shocks on a truck. it discusses the additional travel gained in a shock by mounting at an angle, but also the decrease in shock efficiency when doing this. it should help a bit.

http://www.4crawler.com/4x4/4R_suspension-III.shtml#ShockAngle

this also applies to the spring rate on the coils we have on our shocks, since we are using coilovers.


great question by the way, i'm sure there are a lot of people that don't know about this.

 

[lil' lucifer]

great question by the way, i'm sure there are a lot of people that don't know about this.

I'm just trying to learn the facts about suspensions!



Thanks for everyones answers. Makes sense to me now. But if you got more just keep 'em coming!

 

[robsdak]

L O F-ING L! hate to tell ya but shock angle changes alot, more then just ride hight. it will change thinks like ride high, progression rate, dampaning / rebound rates, amount of suspention travel blah blah blah... dont beleive me?

try this.. (sorry i suck at explaining things), take a loose shock put one end on the ground and hold the other, with the other hand lift the bottom of the shock up (keep the top perfectly still) compress the shock so that the bottom is 1" off the ground, take not of how much pressure ur applying and how much shock travel you have cycled threw. now hold the shock 45* once again hole the top station ary and lift the bottom of the shock one inch, makeing sure you follow a vertical plane, you will use less pressure and the shock will have compressed less


and there is differnt spring rates for fine tuneing, why do u think? a vertical shock with a soft spring will be as stiff as it can get, but what happens if u want somthing stiffer, well u need a stiffer spring obviously

L O F-ING L you are right you suck at explaining things... try this link and read a little about shocks..

http://en.wikipedia.org/wiki/Shock_absorber#Explanation

 

[Harvo]

if you already know , why ask??? on the frame i am running, it doesn't do anything but change the ride height. but you know better than i do.. no i don't run an expensive "comp" chassis, it is a Rock Rider from RC4WD.

and moving shock locations, it changes the ride height and suspension travel IE: before it bottoms out. has not a thing to do with compression of the shock. 2lbs at 90 degrees is 2lbs at 45 degrees..

now changing your pre-load will change the way a shock acts.

let me ask this, in theory, if it change;s things so much. why is there different spring weights? hard , medium, soft?

Easy dude. No flaming in the Newb section. :|

 

[War Pig]

if you already know , why ask???

Because this is the newbie section, and any question is a good question.

and moving shock locations, it changes the ride height and suspension travel IE: before it bottoms out. has not a thing to do with compression of the shock. 2lbs at 90 degrees is 2lbs at 45 degrees..

It absolutely changes the way the shock acts. The more you lay the shock down, the easier it is to compress, and the more travel you can get out of it. It's called leverage.

now changing your pre-load will change the way a shock acts.

let me ask this, in theory, if it change;s things so much. why is there different spring weights? hard , medium, soft?

Different spring weights are for tuning a shock. You can also put harder springs on a shock if you lay them down, and the leverage created makes the shock too easy to compress. Changing pre-load also does this, just in smaller increments than changing an entire spring.

 

[robsdak]

Easy dude. No flaming in the Newb section. :|

your right, i forgot where i was at... i just need to stay out of the 'newb" section. my bad and apologies... i can see what i say gets taken out of context.

 

[ultimate_monkey]

LO Finf L, the shocks we use are technicallt coil overs , providing they are used with external springs, not just a plan old shock absorber.

 

[dannyc]

I've been wondering about shock angle as well. I found that making 1:1 scale drawings helps a lot and is a good way to find out exactly how much leverage on the shock to use to get the right amount of travel and ride height.

You can simulate the movement of the trailing arms and upper links with the use of a compass, and provided you know the shock stroke you can draw out the entire range of travel. I have made a lot of simple drawings from a side elevation like this.

I started by drawing a trailing arm and positioning the shock in the middle of the trailing arm and the shock at 90degrees. Map out the entire range of wheel travel from minimum to maximum and measure the wheel travel.

Then try the same but draw the shock at 45degrees. Again measure the entire travel range. Then you will realise how much it affects wheel travel.

Obviously only change 1 thing at a time (like shock angle or position of shock along the lower trailing arm) when drawing designs to make it a fair experiment. But try loads of different combinations because you’ll probably have to find a compromise.

However, I have no idea how to work out how the shock will be affected throughout the stroke. A shock that is mounted at 45degrees in the centre of the lower trailing arm will be under a lot of stress. Your truck will have a lot of wheel travel, but the shock might be over worked or if it’s too soft you might have loads of negative travel (sag).
If it’s a crawler it might not be so important because of the slow speeds but on a trophy truck type rig it will because of the high speed and big impacts on jumps.

 

[Turn'Nburn]

your right, i forgot where i was at... i just need to stay out of the 'newb" section. my bad and apologies... i can see what i say gets taken out of context.

no....... you definitely need to hang around the newb section, you might learn something.."thumbsup"

 

[robsdak]

no....... you definitely need to hang around the newb section, you might learn something.."thumbsup"

wow, so now i am a dumb ass? i think not... i will just let you "more experienced" guys have it.

 

[robsdak]

LO Finf L, the shocks we use are technicallt coil overs , providing they are used with external springs, not just a plan old shock absorber.

i guess if you would have read the whole article, you might have learned something.. as i said in the previous post. i will let you have it.