Seeking up travel, thoughts on Bilstein 7100s?

PatrickR

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Anyone have experience with 7100s? They are attractive to me for being user rebuildable, and the shorty version is the only decent quality shock that fits (dimensionally) with what I'm trying to accomplish.

Also, any recommendations for shops that work on Bilstein stuff? I'd like to nail down the spring rate I'm pairing it with and get close on valving before I order anything.





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PatrickR

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What are you trying to accomplish?
I use my Jeep for running down rough forest roads more than anything else in the dirt. Suspension performance is ok, but not great (Rubicon suspension on a sport s). I still end up into the bump stop quite a bit, and the rear end tends to step out on successive hits (seems under damped on rebound).

I want to improve damping and increase wheel travel while maintaining a lowish ride height (any increase in height I want to be an increase in available travel). I'm not going to run anything bigger than 33s, so I think I can accomplish this through careful selection of shocks and springs.

I need shocks with a compressed length of no more than 16.25 for the front, and 17.5 rear. I'd like to have extended lengths around 27-27.5 front and 28.5-29" rear. My target for travel is 7" up 4-5" down.

I think I'm constrained to single rate springs to keep the solid lengths short enough.
 

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I need shocks with a compressed length of no more than 16.25 for the front, and 17.5 rear.
Ok, so stock bump stops then.

King 2.0x10" will fit in there if you order them with a welded loop rod end for the front.

King 2.5x10" will fit if you order them with over-cylinder top caps (both front and rear), and a welded loop rod end for the front.

Fox 2.0 shocks for 0-1.5" lift will fit in there but are not easily tuned.
 
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PatrickR

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Ok, so stock bump stops then.

King 2.0x10" will fit in there if you order them with a welded loop rod end for the front.

King 2.5x10" will fit if you order them with over-cylinder top caps (both front and rear), and a welded loop rod end for the front.

Fox 2.0 shocks for 0-1.5" lift will fit in there but are not easily tuned.
I've considered the king's. The big positive is the reputation for quality and a lot of places with experience tuning them. The negatives are they are shorter than the 7100s and end up limiting down travel more than I like, and obviously the price is more. That's sort of what got me interested in the 7100.
 

scrape

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I've considered the king's. The big positive is the reputation for quality and a lot of places with experience tuning them. The negatives are they are shorter than the 7100s and end up limiting down travel more than I like, and obviously the price is more. That's sort of what got me interested in the 7100.
Ah ok. I just looked them up, are you looking at the 12" shorty? That's a pretty cool shock actually. But yea the issue is finding someone who is familiar with valving them.

Also did you measure how much droop you can get without the springs losing preload? You might not be able to run a 12" shock that droops to 28".
 
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PatrickR

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Ah ok. I just looked them up, are you looking at the 12" shorty? That's a pretty cool shock actually. But yea the issue is finding someone who is familiar with valving them.

Also did you measure how much droop you can get without the springs losing preload? You might not be able to run a 12" shock that droops to 28".
Yeah that's the shock I was looking at. I'm trying to get free length and solid length measurements for a few springs that I think might be in the right range. I'll have to rethink some things if it doesn't work out right.

I know the right way to do this would be coilovers and I could adjust for a lot of the parameters that are fixed using the stock mounting; but everything is so close to working the way I want it I figured I would try this route first.
 

Redneck_Jedi

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Morris 4x4 has a great deal on the Fox 2.0 shocks this weekend. I just bought a.full set for like $449 ($476 shipped) with discount code SUS10.
 

AnnDee4444

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I want to improve damping and increase wheel travel while maintaining a lowish ride height (any increase in height I want to be an increase in available travel). I'm not going to run anything bigger than 33s, so I think I can accomplish this through careful selection of shocks and springs.

I need shocks with a compressed length of no more than 16.25 for the front, and 17.5 rear. I'd like to have extended lengths around 27-27.5 front and 28.5-29" rear. My target for travel is 7" up 4-5" down.
I'm not sure you're going to be able to get 7" of bump travel with a lowish ride height.

I haven't personally checked, but I assume that the bumps stops just limit the OEM shocks from bottoming out during vertical axle movement. My stock JLR rides at 20" eye-to-eye in the front, which leaves 4.25" of bump on the OEM shocks (which are 15.75" compressed, Sport = 15.63" compressed). This leads me to believe that you would need about a 3" lift for 7" of bump travel.

Here's some fun numbers I put together based off my stock JLR with hardtop, winch, & steel bumpers:
Capture.PNG
 

Redneck_Jedi

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I'm not sure you're going to be able to get 7" of bump travel with a lowish ride height.

I haven't personally checked, but I assume that the bumps stops just limit the OEM shocks from bottoming out during vertical axle movement. My stock JLR rides at 20" eye-to-eye in the front, which leaves 4.25" of bump on the OEM shocks (which are 15.75" compressed, Sport = 15.63" compressed). This leads me to believe that you would need about a 3" lift for 7" of bump travel.

Here's some fun numbers I put together based off my stock JLR with hardtop, winch, & steel bumpers:
Capture.PNG
Wow! Thanks for doing all the research, so we dont have to. :like:
 
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PatrickR

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I'm not sure you're going to be able to get 7" of bump travel with a lowish ride height.

I haven't personally checked, but I assume that the bumps stops just limit the OEM shocks from bottoming out during vertical axle movement. My stock JLR rides at 20" eye-to-eye in the front, which leaves 4.25" of bump on the OEM shocks (which are 15.75" compressed, Sport = 15.63" compressed). This leads me to believe that you would need about a 3" lift for 7" of bump travel.

Here's some fun numbers I put together based off my stock JLR with hardtop, winch, & steel bumpers:
Capture.PNG
Thanks for the speadsheet, I should have been that organized as I was researching.

I had found the collapsed length quoted as 15.96" (front) for the Rubicon shocks (by shock surplus, I haven't measured myself, but I'd bet your numbers are more accurate), and the collapsed length of the shock I'm looking at using is 16.10". I'll have to find it, but I had another shock manufacturer recommend a shock with the same collapsed length (16.10) as an OEM replacement with no bump needed. Regardless, I don't mind shimming the bump stop 1/4" or so if it's needed when I finally put everything together.

I had read standard up travel is somewhere around 5", I'm sure with a winch and a steel bumper you're probably a bit deeper into your travel than I am (stock plastic bumper). I'd bet a 2" lift for me would end up being somewhat close to what a 3" lift would be for you.
 

oceanblue2019

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Yeah that's the shock I was looking at. I'm trying to get free length and solid length measurements for a few springs that I think might be in the right range. I'll have to rethink some things if it doesn't work out right.

I know the right way to do this would be coilovers and I could adjust for a lot of the parameters that are fixed using the stock mounting; but everything is so close to working the way I want it I figured I would try this route first.
I'd give the guys at AccuTune a call and see what they suggest.
 
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PatrickR

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I'd give the guys at AccuTune a call and see what they suggest.
That was my next step if I couldn't get enough info on the 7100. They only do Fox and King, which don't have an exactly comparable 12" short shock.
 

oceanblue2019

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That was my next step if I couldn't get enough info on the 7100. They only do Fox and King, which don't have an exactly comparable 12" short shock.
They sell service parts for Bilstein so I suspect they might be able to help.
 

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