help with shock length

[jgilbreath]

I know tundra 5100s are popular for 3rd gen t4rs but it seems that there are better options for the rear shocks. I'm not sure i have this correct though, any help or suggestions would be greatly appreciated

Stock lengths: Compressed 12.4 Ride height 16 Extended 19.4

The numbers above yield 3.6" uptravel and 3.4" downtravel.

LC 8 wraps will lift the rear about 3.5" when settled with around 200lbs of additional weight. This would make the shock length at ride height 19.5" correct? So here are a couple of shocks to compare:

Tundra 5100 Compressed 13.8 Ride height 19.5 Extended 22.4

Fox 980 24 675 (4th gen t4r 1" to 2" lift) Compressed 14.95 Ride height 19.5 Extended 23.55

Based on these numbers wouldn't the fox be a much more desirable length as they would have closer uptravel and down travel numbers? Or are the tundra 5100s better because they have more uptravel (but less downtravel) in this scenario?

 

[Stoffregen Motorsports]

Ideally you would match your travel numbers with the shock. These numbers you gave, are they numbers you've measured ? or are they advertised numbers?

I never take any measurements for granted. I always measure my travel and chose a shock length accordingly.

 

[troyboy162]

You'll find straight up and down requires one compressed length and flex requires another. I had ~14.5 compressed and ~24 extended but ended up needing to drop down the frame bumps because it was actually jaming the shocks in the compressed position during flex. Maybe they would have been fine but I decided to play it safe.
I was OK with trading the up travel for extra down travel but that was really only helpful for rocks.
If you are on stock links and running the rear sway bar you likely can't take advantage of a ~24" shock anyhow though

 

[jgilbreath]

The measurements above are advertised lengths, i measured the stock shock at ride height (16").

With a 3.5" rear lift will the shocks new ride height be 19.5"?

If 19.5" is the new shock length at ride height would a shock that gives close to equal up and down travel be ideal?

If i go with the foxes i would lower the bump stops by 2.5", leaving 4.5" between axle and bump stop. That would leave .5" of bump stop compression before bottoming the shock out (based on fox advertised numbers).

The rear will have new coils, shocks, bump stops, brake line, and panhard bar. I will probably not use the entire range of shock travel. Just trying to understand if my logic based on advertised shock lengths makes the foxes a better choice than 5100s.

Thanks for the feedback so far, i have a lot to learn.

 

[troyboy162]

Also remember lift isn't linier to shaft movement since the shock is at a variable angle throughout its range of motion.

I had limit straps in addition to lowered bump stops with my old set up...it was a huge compromise for all around wheeling to increase rock crawling.
With the shocks I have now I just let them get fully compressed during flex since they don't jam. Sucks, but there's no way i foundto bump for flex and not ruin normal travel.