Why are the same stroke shocks longer as dia increases

[84projectFORD]

i get why shocks of larger caliber than 2.5 start to gain length but heres my example.

Fox 14” stroke 2.5 body, 7/8 shaft coilover w/ resi on a hose is 23.44 collasped and 37.44 extended

Fox 14” stroke 2.0 body, 7/8 shaft coilover w/ resi on a hose is 21.1 collapsed and 35.1 extended.

Wheres the extra 2” at?

I ask this because im looking at going to a 2.5 shock on the back of my rig. I dont have to but im borderline on limits of the 2.0 and i want to ditch the foxes for kings to match the front kings. I cannot change my mounts for more length. I cant add more droop without the driveshaft binding. I do, however have a lathe and mill to massage shock parts… if even possible. If i know where the gain is coming from, I’d like to see if i can machine it back down or come up with a work around

 

[Turboyota]

Welded eyelet should get you ~1.5” ish

 

[84projectFORD]

Welded eyelet should get you ~1.5” ish

Have to have a retainer for the spring still though

 

[84Prerunner]

Internal spacer. 2.5s have a bigger droop stop spacer to help keep the shaft in alignment with the seal head. You can easily get 1” of extra travel out of 2.5” shocks. (12” cycling 13” etc)

 

[84projectFORD]

My 2.0’s have a 1” spacer in them as well. They will go from 14” to 15” if i take out the spacer so seems the same still???

 

[84Prerunner]

My 2.0’s have a 1” spacer in them as well. They will go from 14” to 15” if i take out the spacer so seems the same still???

2.5s. Have a bigger spacer.

 

[84projectFORD]

Any pics for comparison or measurments?

 

[the bodj]

Have to have a retainer for the spring still though

They make low profile spring retainers. I see them a lot on older kings. Not sure why they went to the much taller retainers...

 

[84projectFORD]

They make low profile spring retainers. I see them a lot on older kings. Not sure why they went to the much taller retainers...

Thats no issue, ill probably use the preload retainers (tapered ones) but when you weld an eyelet to the shock shaft, they are typically for shock only apps, not coilovers so no need to worry about the area the retainer sits on, on the eyelet. In my case, i need that ability.

 

[84projectFORD]

Ah this must be one of the grear mysteries of the shock world

@ADSRACINGSHOCKS has gotta know

 

[DialedShockPrep]

I just went through a similar issue on a customers tube chassis baja bug.. It’s got some odd geometry and we couldn’t find springs big enough for the 2.0” coil carriers so i convinced them to put some 2.5” remote resi coilovers on the back. Dumb me didn’t realize that there was a length difference so we ended up having to swap to the short -1” rod end on the coilovers and a +1” on the bypass to get the car to cycle better.
The difference in length lies in the smaller diameter bearings in the top caps and rod ends which makes the top cap and rod end smaller, and the wiper cap is also thinner. Also because the shafts are smaller the resi hose size can decrease so that makes the top cap even shorter. Piston height also plays a role as well.