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Old 05-11-2005, 01:10 AM   #1
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Default Innovative idea or just plain stupid??? You tell me.

Hey all, I just came up with an idea that really seems smart, yet is so obvious that nobody has ever really proposed it.

Check it out:

I'm going over my new X-Ray '05 and after building the shocks, I placed one of them on the car upside-down, I just wasn't looking when I did it.

Now here's the deal...

RC and 1:1 racing cars are always looking for ways to :

1. Reduce sprung weight

2. Lower CG (Center of Gravity)


Why are we mounting our shocks the way we do??? If you want to lower the sprung weight and lower the CG then,

TURN YOUR SHOCKS UPSIDE-DOWN!


I know it sounds stupid, but read on...


I got this idea because in 1:12th we mount our shocks "upside-down" to help prevent oil leakage. It doesn't effect the shocks operation in the least, so thatís just what we do.

Now in Touring car (and every other form of RC), you have shocks sitting with their shafts pointing down and over time you do leak some oil, so turning them upside-down would definitely help with long-term oil leakage.

*Also of note, because the shock shafts would be higher up, they would be less prone to getting as dirty as they do now.

Next is sprung weight.

With the shocks in their "normal" orientation, the bulk of the shocks weight is carried by the chassis via-the shock towers. As the springs resist the weight of the car, they are also resisting the weight of the shock itself.

Now if you reverse the shock, the weight of the shock is now carried by the suspension arm and is now "unsprung" since the shock body is now UNDERNEATH the spring.

This does add to the unsprung weight of the cars arms however, yet the change should be minimal.

Last but not least, by having the shocks upside-down, you obviously lower the car's CG or Center of Gravity. As we all know, having a lower CG allows higher corner speeds and reduced body-roll.


So there you go, by simply turning our shocks upside-down, we gain:

1. Reduced oil leakage

2. Potentially cleaner shafts and longer life for O-Rings

3. Reduced sprung weight for quicker maneuvering

4. Lower overall Center of Gravity


I'm gonna really try this out to see if it works any better. It really should....in theory.

Lemme know what you all think...
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Last edited by Soviet; 05-11-2005 at 01:18 AM.
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Old 05-11-2005, 01:17 AM   #2
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good idea i might try that
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Old 05-11-2005, 01:18 AM   #3
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i don't it will be possible in all cars... because shock caps may touch arm, otherwise an interesting point try out on the track and let us know.
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Old 05-11-2005, 01:22 AM   #4
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With your method, up side down : you need to make sure there is no trap air inside the shock, otherwise you hear "squirts" sound. You can do that by completely fill up the shock including the membrane too. Some shocks can do, but some don't. Once I tried in MTX3 to reduce dirty oil shock, but it's not possible because I can hear the squirt sound.
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Old 05-11-2005, 01:22 AM   #5
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Quote:
Originally posted by Exe
i don't it will be possible in all cars... because shock caps may touch arm, otherwise an interesting point try out on the track and let us know.
I will!

Since the diameter is the same at the bottom as the top, it should work.

You are right however that some cars may rub, however if your wheels don't rub after inverting the shocks, it's worth trying.
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Old 05-11-2005, 03:03 AM   #6
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I think you've got your physics slightly worng.

Mounting shocks upside down WILL lower CofG.

However it WON'T lower unsprung weight.

Unsprung weight is the weight of the suspension components and wheels that are controlled by the springs. If you turn the shock upside down, you are ADDING the weight of the shock bodies to the unsprung weight.
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Old 05-11-2005, 03:23 AM   #7
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I think it wont matter which way you run the shocks in relation to your performance.

What matters to me though, is that my expensive shocks dont get damaged. Anyone who has broken arms while running their cars would cringe at the thought of their precious shocks taking the brunt of the impact.

At least if your shocks are mounted the right way, you only stand to lose your lower shock mount or in the worst cases, a bent shock shaft.

Besides, this has been tried by other people in the past. There's got to be a reason why most people dont run their shocks that way.
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Old 05-11-2005, 04:01 AM   #8
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Quote:
Originally posted by sosidge
I think you've got your physics slightly worng.

Mounting shocks upside down WILL lower CofG.

However it WON'T lower unsprung weight.

Unsprung weight is the weight of the suspension components and wheels that are controlled by the springs. If you turn the shock upside down, you are ADDING the weight of the shock bodies to the unsprung weight.
Read again...I said it would increase unsprung weight and would decrease sprung weight.

I'll quote myself:

"Now if you reverse the shock, the weight of the shock is now carried by the suspension arm and is now "unsprung" since the shock body is now UNDERNEATH the spring.

This does add to the unsprung weight of the cars arms however, yet the change should be minimal."

"3. Reduced sprung weight for quicker maneuvering"


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Old 05-11-2005, 04:04 AM   #9
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Quote:
Originally posted by Entropy
I think it wont matter which way you run the shocks in relation to your performance.

What matters to me though, is that my expensive shocks dont get damaged. Anyone who has broken arms while running their cars would cringe at the thought of their precious shocks taking the brunt of the impact.

At least if your shocks are mounted the right way, you only stand to lose your lower shock mount or in the worst cases, a bent shock shaft.

Besides, this has been tried by other people in the past. There's got to be a reason why most people dont run their shocks that way.
Yeah...impact would potentially rip off a shock-cap if mounted inverted. Still, I'm gonna try it out to see if there are any benefits on the track. Perhaps a gain of 0.1 - 0.3 seconds on the infield due to quicker transitions ???
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Old 05-11-2005, 04:10 AM   #10
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thats a preety smart idea man......im gonna give it a go...i hope xray shocks will fit upside down lol
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Old 05-11-2005, 04:52 AM   #11
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Quote:
Originally posted by pink pac man
thats a preety smart idea man......im gonna give it a go...i hope xray shocks will fit upside down lol

dude this idea has been done before, it's no big woop. IV'E DONE IT!

i've been doing this with my mugen mxt3 prospec. it works fine.

another advantage is that because the shocks are upside down the air inside the shocks can come out easier (ie upside down, air rises to the o rings and comes out. shocks right way up air goes to cap, no where else to go.

it works fine.

i've done this for a while and cuz i'm not quick all the quick guys sort of laughed at me, when i explained it some of them, shut up as if they got the idea others then raised the (valid i think) point of the weight being on the arms as oposed the the main body of the car.

either way it works and the weight on the arms doesn't seem to be an issue. go for it!! you might encounter the problem on some cars of the cap of the shock hitting the arm. in this case use a longer screw and space it out just a touch.

ALWAYS TRY TO BE DIFFERENT!! that's my motto to life.
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Old 05-11-2005, 05:17 AM   #12
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I've been doing this for ages on my mini, since i couldn't fit all my electronics into the chassis but still wanted to lower the CoG i flipped my shocks. On my TC i don't feel the need, getting ride height and roll-centre right would make a larger difference in overall performance.
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Old 05-11-2005, 05:20 AM   #13
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Quote:
Originally posted by Soviet
Read again...I said it would increase unsprung weight and would decrease sprung weight.

I'll quote myself:

"Now if you reverse the shock, the weight of the shock is now carried by the suspension arm and is now "unsprung" since the shock body is now UNDERNEATH the spring.

This does add to the unsprung weight of the cars arms however, yet the change should be minimal."

"3. Reduced sprung weight for quicker maneuvering"


Sorry I misread, I had never seen the term "sprung weight" before.

Everyone in motorsport is trying to reduce UNsprung weight for better suspension response - I don't know why you are trying to increase it. It's the tyres that touch the ground, not the chassis.
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Old 05-11-2005, 05:27 AM   #14
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Quote:
Originally posted by sosidge
Sorry I misread, I had never seen the term "sprung weight" before.

Everyone in motorsport is trying to reduce UNsprung weight for better suspension response - I don't know why you are trying to increase it. It's the tyres that touch the ground, not the chassis.
Unsprung = not sprung

Sprung = sprung



Yeah, it would increase weight on the arms, however I'm guessing that since our models are already quite light that the performance hit compared to potential gains would be negligible.

*Reason for the running commentary:

Doing anything to avoid working on Thesis.......
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Old 05-11-2005, 05:38 AM   #15
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Soviet,

Please don't take any of the following in the wrong way, but I do think you have your wires crossed a little here.

Your spot on that lower CofG is beneficial, but rarely at the expense of increased unsprung mass for several reasons. Also in this circumstance I think that the relative reduction in CofG height would be almost immeasureable.

A reduction of total vehicle mass will aid direction change. However, there is no sense in trying to reduce the sprung mass by increasing the unsprung mass in any circumstance, be it 1/10 scale or real cars.

Second to that we are usually running to a minimum weight limit and so we are stuck with a total mass for the vehicle.

Unsprung weight is a term used to describe the parts of any vehicles mass that is directly connected to the wheels and therfore isolated to the chassis (sprung mass) through the suspension. So wheels, tyres, wishbones, uprights, wheel bearings etc are all unsprung mass. The spring is the only exception to this as it is part spung, part unsprung.

As unspung mass increases, greater inertia builds in the suspension system, SLOWING DOWN its ability to respond to fast direction changes and degrading traction due to the reduced ability of the suspension to control the minute and high pitched occilations you see on the tyre surface contact patch with the road.

All in all, light unspung mass is definately No1. Formula 1 teams do not spend hundeds of thousands of $ manufacturing light weight carbon fiber wishbones and exotic alloy uprights when the car is already 75kgs underweight for no reason.

If you gain 0.1 - 0.3 seconds a lap by turning your shocks upside down, i'd like to fly to the US and marry you!

Last edited by Spud_J; 05-11-2005 at 07:34 AM.
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