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droop measurement question.

droop measurement question.

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Old 05-24-2013, 10:23 AM
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Default droop measurement question.

I know the Hudy setup uses a block under the chassis and measures arm height above chassis height by my question is this. Ride height will affect droop but cannot be measured using the droop gauges in this fashion. IE., you measure your droop at 6 on the gauge but you've got your collar way up on the shock for a low ride height which causes the car to have much more droop than it'd have if the collar was way down the shock body for a higher ride height. How do you measure droop and compensate for this using a HUDY gauge? Using a ride height gauge and lifting the car w/ tires on it will quantify this measurement but the Hudy gauge can't can it?
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Old 05-24-2013, 10:50 AM
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Originally Posted by TT_Vert View Post
I know the Hudy setup uses a block under the chassis and measures arm height above chassis height by my question is this. Ride height will affect droop but cannot be measured using the droop gauges in this fashion. IE., you measure your droop at 6 on the gauge but you've got your collar way up on the shock for a low ride height which causes the car to have much more droop than it'd have if the collar was way down the shock body for a higher ride height. How do you measure droop and compensate for this using a HUDY gauge? Using a ride height gauge and lifting the car w/ tires on it will quantify this measurement but the Hudy gauge can't can it?
No, it can't.

But you do know that if your ride height is, say, 1mm higher than normal, the droop block needs to give a reading 1mm less than usual to give the same actual droop.
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Old 05-24-2013, 11:28 AM
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I guess my quesiton when I see people listing ride height using the hudy gauge that means nothing unless you know their ride height also correct?? IE, the xray manual says 6f//5r droop but that is only at the 5.2/5 mm ride heights they specify then correct?
If i were to go to a ride height of 5.7/5.5 I'd need the droop gauge to read 5.5/4.5 If I'm understanding this correctly.
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Old 05-24-2013, 11:33 AM
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Originally Posted by TT_Vert View Post
I guess my quesiton when I see people listing ride height using the hudy gauge that means nothing unless you know their ride height also correct?? IE, the xray manual says 6f//5r droop but that is only at the 5.2/5 mm ride heights they specify then correct?
If i were to go to a ride height of 5.7/5.5 I'd need the droop gauge to read 5.5/4.5 If I'm understanding this correctly.
It also assumes your wheel size is identical. Change the ride height, tire/wheel size and your droop amount changes for a given downstop measurement (which is what the guages are actually measuring).
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Old 05-24-2013, 11:38 AM
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Originally Posted by TT_Vert View Post
I guess my quesiton when I see people listing ride height using the hudy gauge that means nothing unless you know their ride height also correct?? IE, the xray manual says 6f//5r droop but that is only at the 5.2/5 mm ride heights they specify then correct?
If i were to go to a ride height of 5.7/5.5 I'd need the droop gauge to read 5.5/4.5 If I'm understanding this correctly.
You're correct. You would need to know the droop gauge reading, the ride height, and wheel size in order to replicate the setting. This is why people frequently specify droop relative to ride height. ie. 2mm "over ride height", or "uptravel"
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Old 05-24-2013, 11:47 AM
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I always measure the uptravel. It's the simplest way to do so.
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Old 05-24-2013, 11:53 AM
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Here's an alterative method: I find this give a very accurate measurement.

http://www.tamiyausa.com/articles/fe...article-id=413

I have used droop blocks as well as the up travel method. The thing about droop and setup sheets ( plus what has been mentioned previously) is it's all depends on the point of reference, difference in uprights (f/r), etc all relate to the readings.
Jun's method keys off the important points: wheel diameter & ride height
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Old 05-24-2013, 11:53 AM
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Thanks guys I think I'll continue to measure w/ mm above ride height for droop. Seems there are too many variables to consider when trying to compare. I don't even know what the xray t4 manual is using for tire diameter when they specifiy a starting droop.

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Old 05-24-2013, 12:20 PM
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Yeah, don't confuse measuring droop, with measuring your downstops. They are related, but not the same thing.

I personally never measure my downstops, as it doesn't appear to be relevant to anything the car is going to be doing, once loaded and sitting on the table. You still have to set ride height, and your actual droop afterwards anyway. I measure RH with a RH gauge, and droop with a metric ruler. I fine tune my left and right sides by looking at the car at eye level, and slowly picking the car up and seeing which tire leaves the ground first. .. .make them the same, then measure the total amount of up-travel before the tires leave the ground (which is your droop).... then increase or decrease equally on both sides as you desire. Piece of cake.

Don't forget, check/reset BOTH your ride height and droop, after changing tires too, as different sets can be different sizes.
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Old 05-26-2013, 05:42 AM
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Default Yes it can.

Originally Posted by sosidge View Post
No, it can't.

But you do know that if your ride height is, say, 1mm higher than normal, the droop block needs to give a reading 1mm less than usual to give the same actual droop.
The HUDY gauge is stepped to allow for the blocks under the car,so yes it can.
But I measure droop either with a ruler or a Yeah Racing droop gauge running directly off the chassis.
All you need is the YRacing tool,1.5 mm tool,and you pick up the car and wander around to buy your long awaited hot dog,whilst adjusting droop!
Tim
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Old 05-26-2013, 02:56 PM
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Seems that mm above ride height the most accurate but i still double check with my hudy blocks just to make sure the setting is even L/R.
Some tires can be deformed as well so id only reallu trust orh on new tires and compare it to downstop numbers.

But i still noob. Many different ways to arrive at the same thing. One thing i like about he hobby
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Old 05-26-2013, 03:16 PM
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what is generally acceptable droop as a starting point using over ride height? I started at 2mm over ride height but I think I ended up at 2f/3r over ride height to help w/ off power steering.

Dave
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Old 05-27-2013, 01:07 AM
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Below are some posts I made a number of years ago on measuring droop that may be of use:


http://www.rctech.net/forum/nitro-ro...ml#post4736209

http://www.rctech.net/forum/8487552-post21.html
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Old 05-27-2013, 08:04 AM
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[QUOTE=calvin;12193647]Below are some posts I made a number of years ago on measuring droop that may be of use:




well I guess you learn something every day, it would seem I have been doing it wrong for years, no wonder the car doesn't handle well.
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Old 05-28-2013, 09:22 AM
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