Another One for the Shock Tune Wizards!

GGRR 4555

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Howdy folks!! Took the fox 2.5 coilovers off the front of my Ultra 4 4500 class Jeep TJ.

My goal is to firm up the compression damping by 15% and free up the rebound damping by 10% approx.

Attached is a photo of my shock valving. Please tell me what to change to achieve close to desired results. Note that rebound and compression are flutter stacks.
 

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GGRR 4555

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What have you tried set-up wise, so far ?
I worked with a tuner to get the car where it is. I don’t know what changes were made during that process to the shims. I hope to tune the car again someday but with two new babies at home there is no way I will have the $$ for a full tuning sesh for a while.

Trying to make some changes while I’m in here to move in the right direction.
 

turbodon

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Have you tried it without the compression flutter? Do you have a video of how the car works? Do you have a hydro bump or does it bottom on the shock?
 

GGRR 4555

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Have you tried it without the compression flutter? Do you have a video of how the car works? Do you have a hydro bump or does it bottom on the shock?
I have not tried it without the flutter in recent history. That could be an option. The car has hydro bumps so the last 1/2 of shock travel is seldom used.

Sadly I do not have video of it in the bumps from this current configuration.
 

Bebop

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1/2 of the travel under bump stop seems overkill, doesn't it ?

Does the piston has free bleed holes in it ?
 

GGRR 4555

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1/2 of the travel under bump stop seems overkill, doesn't it ?

Does the piston has free bleed holes in it ?
It’s a solid axle and the air bumps are slightly inboard of the coilovers. Need the 1/2” to protect from bottoming when flexing the Jeep out. Just doesn’t use that 1/2” when smashing whoops strait on.

Yes it has 3 free bleed holes
 

partybarge_pilot

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3 bleeds open and a flutter stack? So no low speed damping to speak of.

Minus the flutter on comp you are just about maxed out before you start having cavitation issues. Reb is also very light. Not sure you could go any lighter without bending shims.
 

Bebop

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It’s a solid axle and the air bumps are slightly inboard of the coilovers. Need the 1/2” to protect from bottoming when flexing the Jeep out. Just doesn’t use that 1/2” when smashing whoops strait on.

Yes it has 3 free bleed holes
You said 1/2 of travel, not 1/2" in the previous post.

Close a bleed hole and see what it does.
 

jon coleman

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my straight axle articulated head on hits to 3/4", of left over front shock travel, at full left or right smash, bump& shock were close, about 1/ 4" left on shock travel, , never smashed the zipp tie travel indicators, but they were bottomed out,rear was about a strong 1 /2", thats about right
 

brad inch

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your valving is very lite.to get what you are asking.i think is little heavier spring would do what you want. more compression and faster rebound.
good luck brad
 

GGRR 4555

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Ok so let’s say I leave the rebound stack alone.

On compression: Could I add another 1.8” shim at the top of the flutter stack? I could put a 1.8” .015 under the current 1.8” shim.

Cons?
 
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