FOA shock pre-use tune up.

[2012SVTSC]

Oops! How bad did it get the shock body? or did it just grab and stick in place pretty much?

The body had a few minor scratches, I did my best to de burr them.

I switched to a old style fox high flow 3.5" piston. I reduced my compression valve stack substantially but installed a rate plate, and installed a 1" top out spacer. With FOA's "new" seals and I decided to stick with the standard orings.

Shock pictures:

 

[Hi-Desert Motorsports]

nice! that fox piston is gonna put in work! I am curious why you chose a rate plate setup rather than a traditional stiffer stack?

 

[84Prerunner]

Running a fox piston in my FOA 3.5 as well. Had to Maching down the OD and wear band depth a little bit works great.

 

[84Prerunner]

nice! that fox piston is gonna put in work! I am curious why you chose a rate plate setup rather than a traditional stiffer stack?

I use them in bypasses to get a firm bumpzone

 

[2012SVTSC]

nice! that fox piston is gonna put in work! I am curious why you chose a rate plate setup rather than a traditional stiffer stack?

For my truck, with the leafs and fairly light rear end my worst enemy is washboard and chop. The Fox piston I am using dose not have any freebleed holes. I am floating my compression valve stack with a 1.6x.004 shim before the first shim for free bleed. This should cause my shock to have super low break away force especially with the ultra slim valve stack I have, which is:

=====Piston
-----1.6x.004...free bleed valve float shim
_____ 2.3x.008
_____ 2.15x.008
_____1.85x0.010
_____ 1.55x0.015
_____ 1.3x.010 pivot shim
_____ 1.3x.015 rate plate lift
::::::: rate plate 1.973x .185

so with the light valveing I have chosen to handle the small washboard I hate, I needed the rate plate for bigger hits, and because I have 3 compression tubes the linear rate will be easier for my brain to tune with the bypass tubes.

Atleast thats my thoughts on that and why i set it up like this.

Running a fox piston in my FOA 3.5 as well. Had to Maching down the OD and wear band depth a little bit works great.

Glad to hear it! I just had to machine the center from 1/2 to 5/8" the od was literally the exact same!

 

[2012SVTSC]

Fox v FOA for reference:

 

[Hi-Desert Motorsports]

I use them in bypasses to get a firm bumpzone

they definitely do the job there! We just tuned a single shock ranger that had front IBP's, the main valving stack had a rate plate that was absolutely critical to get the truck to work well in the smaller holes and still take the big holes without harsh bottom outs! I used to be against them, but after tinkering with them for a while I definitely see where they have their benefits and place!

 

[Hi-Desert Motorsports]

For my truck, with the leafs and fairly light rear end my worst enemy is washboard and chop. The Fox piston I am using dose not have any freebleed holes. I am floating my compression valve stack with a 1.6x.004 shim before the first shim for free bleed. This should cause my shock to have super low break away force especially with the ultra slim valve stack I have, which is:

=====Piston
-----1.6x.004...free bleed valve float shim
_____ 2.3x.008
_____ 2.15x.008
_____1.85x0.010
_____ 1.55x0.015
_____ 1.3x.010 pivot shim
_____ 1.3x.015 rate plate lift
::::::: rate plate 1.973x .185

so with the light valveing I have chosen to handle the small washboard I hate, I needed the rate plate for bigger hits, and because I have 3 compression tubes the linear rate will be easier for my brain to tune with the bypass tubes.

Atleast thats my thoughts on that and why i set it up like this.

Glad to hear it! I just had to machine the center from 1/2 to 5/8" the od was literally the exact same!

Makes sense! did you not wanna drill and tap the piston for added free bleed? Its what we have done in the past to help with chatter, But as you said it has that negative affect on the bigger hits that you always must keep into account. Was talking with Sonny from Downsouth at the expo and we both had the same conclusion with shock tuning, Theres countless different ways to achieve a great result in shock tuning! Looking forward to see how your truck works

 

[theycallmeWALLY]

This thread is rad!

I messed with my FOA's back in the day. Ended up just going with King stuff but it was a great way to learn about shocks and trying new things.

 

[Tree trunk]

Are you still running these? I know this is an older thread. Any updates?

The bypass chatter in the bronco is pretty damn rowdy.
Not a big deal for the fellas with head sets on.
But keeping a head set on a 2 year old might be difficult.

The rear of the bronco works great with the king 16” 2.5 bypassess, but there is no doubt that I will cook those shocks after miles of whoops.

I’ve been throwing around the idea of getting some of the 3.5” FOA reservoir shocks to stick on the rear of this thing.
It’ll eliminate the bypass chatter…. And maybe help keep up with the front….

My question is….

Do you think a 3.5” non bypass shock would be able to rebound fast enough to work well on a leaf spung truck?

I’m sure I could essentially take the valving down to nothing…. But I also feel like there would need to be some sort of valving on the rebound side…

I could even go old school and weld in my own “free flow” bypass tube.
That could help with the washboard harshness, but keep the valving frim at the top and bottom of the stroke.

For $360 per shock…. Might be worth looking into.

What do you guys think?

 

[philofab]

The bypass chatter in the bronco is pretty damn rowdy.

Just replace the bypass valve pistons ends with delrin. Makes them way quieter. If I remember right King makes both, the loud is a "race" valve and the quiet one is a "prerunner" valve. Another thing to do it replace the com10 call at the top with a rubber bushing.

 

[Tree trunk]

Shit I’ll give that a try first,
I need to lighten up the valving anyways so I might check out the delarn seats.
Thanks dude

 

[2012SVTSC]

I do still run the FOAs on the rear of my raptor.

At this point they work good. I rebuild them build every season, but they do not leak. Its more for me to inspect and tune them.

Most recent rebuild I did these adjustments:
1. Fully deburred the bypass plungers

2. Changed the seal head to their new design.
The new design moves the snap ring grove so the wiper seal sits better on the shock body.

3. Revalved with below stack, and used a 5/8 saftey washer as the clamp washer for rebound to reduce the pivot diameter.

4. Installed new version resivor pistons. The new version is hollow, like a cup the old version is a full slug. New version is much lighter.
New raptor stack: (older high flow fox piston form kartek)
All the shims are either king or SDI, or hand polish/sanded FOA
Rebound:
1.15 -- .008
1.3 --- .008
1.5. ---- .008
1.65 -----.008
1.8 ------ .008
1.9 ------- .015
Piston
2.352 --------- .015 (this is a polished foa shim)
2.3. -------- .008
2.15. ------- .008
2.05. ------ .008
1.85. ------ .010
1.6. ---- .004
1.55. --- .015
1.3. -- .10
1.3. -- .15
Compression

Other thing I do now: lube all the o-rings with a metric shit load of slick-honey moto lube.
Pack the space between the seal head and wiper seal holder with pet/Vaseline.
Pack the top of the bypass plungers with Vaseline.

I use shock seals.com oil.

Anyway yeah still use them and tune them but I do not recommend the "clicker adjusters" they become very hard to adjust with 200 psi of nitrogen, so I recommend the norm Allen key one for FOAs.

As far as not using bypasses and just their 3.5 smoothies, I doubt you will be pleased.

Also the foa bypasses click pretty loud aswell.

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