Rear shock sizing help needed (real numbers provided)


Irun

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Part # 1 - Background: Okay folks I need to tap into the knowledge bank here. I'm part way through the build of my TJ and I'm stuck on how to proceed with the rear shocks. The Dana 44 rear is setup with the following:

- H&R 52107 Springs (Netted 1.5" lift)
- Savvy Body Lift
- Currie Rear Track Bar, with Currie re-location bracket
- Savvy Control Arms
- Savvy UA

I cycled the suspension and determined I needed 1" bumpstops, to keep the Currie track bar approximately 1/2" from hitting the bottom of the tub at full stuff.
icogsec-jpg.jpg

i2jmbcs-jpg.jpg


When checking for shock lengths, measuring eye-to-eye, I came up with:

- 13 1/4" Collapsed
- 17" Ride Height
- 22 3/4" Extended (It's at this point that the spring starts to unseat)
20210402_205547-jpg.jpg
 
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Irun

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Part #2 - The Math: If i run the numbers, I end up with a best case 9.5" of shock travel. If I was able to get a 50/50 travel, that means 4.75" up and down. Based on the Spring & Shock thread, the nearest option I can find is OME N67. However, when looking at the number (13.3" Collapsed and 22.1" Extended). That means my real numbers would look like this:

- 3.7" up travel
- 5.1" down travel
- 62/38 split

These numbers don't look optimal for me, so am I accepting this, or is there a custom option?

Edit: When I looked at this last week, I could have sworn I saw the N67 available, but now it's showing "no longer available" The means the next best is the OME 60049. The numbers are slightly different, but close enough for the discussion here!
 
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IrishWake

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Isn’t a 13.3 compressed going to bottom out with your current bumpstop, or am I reading this wrong? I’m assuming your 13.25 collapsed measurement was taken with the 1” bumpstop added or taken into consideration
 
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Irun

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Isn’t a 13.3 compressed going to bottom out with your current bumpstop, or am I reading this wrong? I’m assuming your 13.25 collapsed measurement was taken with the 1” bumpstop added or taken into consideration
The collapsed measurement was taken with the 1" bumpstop. Given the size of the H&R spring coils, I'd be shocked if the suspension would ever compress fully.
 
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IrishWake

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The collapsed measurement was taken with the 1" bumpstop. Given the size of the H&R spring coils, I'd be shocked if the suspension would ever compress fully.
That’s something I had not considered. I guess most of my shock fitment issues have been in the front, I forgot how little space there is between the rear pads at compression
 
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Can the Currie track bar live in the factory mount?
That's definitely a limiting factor. However, with the Savvy UA it needs to be there, due to the pinion angle. I'm wondering what impact a 1" rear spacer would have? I was hoping to not go that route, but may need to test it and look at the numbers. :unsure:
 

jjvw

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That's definitely a limiting factor. However, with the Savvy UA it needs to be there, due to the pinion angle. I'm wondering what impact a 1" rear spacer would have? I was hoping to not go that route, but may need to test it and look at the numbers. :unsure:

Unless you specifically want or need the low ride height, I would look at a bit more spring lift to help the shock numbers.
 
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Irun

Irun

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Unless you specifically want or need the low ride height, I would look at a bit more spring lift to help the shock numbers.
I have a new set of 3" Nth Degree springs that I'm going to test fit. However, this will result in 4.25" lift on a 31" tire. I already know I won't like the look!
 
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