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How do I measure for shocks?

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Old 06-26-2011, 07:50 AM
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How do I measure for shocks?

IS THERE SOME KINDA MATHMATICAL FORMULA TO FIGURE OUT HOW LONG A FRONT SHOCK NEEDS TO BE FOR MAX. UP AND DOWN TRAVEL????? this is for a 84 4runner with approx. 5 1/2 inch front lift kit.???? thanks.
Old 06-26-2011, 09:16 AM
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It's mythical device known to mammals that walk upright. It's called a





















tape measure.

:wabbit2:
Old 06-26-2011, 09:22 AM
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http://www.bajataco.com/travel-measurement.html


Old 06-26-2011, 10:17 AM
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Originally Posted by yotadoug
IS THERE SOME KINDA MATHMATICAL FORMULA TO FIGURE OUT HOW LONG A FRONT SHOCK NEEDS TO BE FOR MAX. UP AND DOWN TRAVEL????? this is for a 84 4runner with approx. 5 1/2 inch front lift kit.???? thanks.
http://web.archive.org/web/200003010...ta/travel.html

And:
- http://www.4crawler.com/4x4/4R_suspe...ml#SpringSpecs
Old 06-26-2011, 10:22 AM
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ahh......thats what they call that measuring whats-a-call-it!
actually....maybe i didnt ask the right question? so ...ill try again........over all dimension from bottom of center of hole to the bottom of shock tower? then...?.....do you want the dimension of half of the shock arm, so that you have the same amount of travel up as you do down?????im guessing?
Old 06-26-2011, 10:24 AM
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im sure this isnt some kind of rocket science but the last lift kit i installed came with the shocks...and they where already the correst length...so there was no thinking envolved..basic r&r.......
Old 06-26-2011, 10:37 AM
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An noted on the article I posted is that you try and determine the minimum compressed length that the shack needs to fit, that is with the axle up against the upper bump stop. The shock should be shorter than this when compressed (i.e. it's compressed length). If it is longer than that, your shock will become a bump stop and limit up-travel and shocks don't like being bump stops, can damage them.

Then you have the fully extended length at full suspension droop. Ideally you want the fully extended shock longer than this so it does not limit down travel.

What length shock you can fit will also depend on how you are mounting it. With stock mounting points, you'll probably find a max. length shock, like I posted on the 2nd link above. Basically I used the max. compressed length shock I could find and then let it slightly limit droop, not ideal but you live with what you have. I later went with a floating upper shock mount to let a much longer shock fit in place and I no longer have any shock-limited front travel:
- http://www.4crawler.com/4x4/4R_suspe...ngTravelShocks

Assuming you have shock mounts that allow a long enough shock to fit and you are asking about what percentage of up and down travel to allow, again it sort of depends on the vehicle application. If doing a slow speed rock crawler, you don't need as much up and down travel. Since extra up travel is basically added height and you want the vehicle as low as possible, you might have say 30% up and 70% down travel for example. For a high speed desert pre-runner on the other hand, you might want more like 50/50 on the up/down travel so you have lots of up travel to soak up high speed bumps.
Old 06-26-2011, 10:52 AM
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outstanding......thats what i needed confirmed....i was close.........not a rockcrwler but she will get me in and out....thanks for your time.....
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