Bilstein 6112 2.5" Front Lift, 2" Toytec Rear Springs with either FOX or ICONs..??

[fromLRtoT4R]

Bilstein 6112 2.5" Front Lift, 2" Toytec Rear Springs with either FOX or ICONs..??

I recently went form a Land Rover LR3 to a 2007 4R SR5 4x4.. Its hasn't been 2 weeks before the 4R had its first upgrades come in.. I could not stand that rear in the air and low front end look, and it just did not have the ground clearance..
Anyway, here is what has been installed.....
FRONT = 2.5" Bilstein 6112 Shock and Spring (Digressive)

REAR = 2.0" Toytec long travel springs.. Now here is the tricky part..... I was convinced that I wanted a progressive rear shock so I went with FOX. Shortly after I place the order, I realized that the Bilstein 6112 is a digressive shock, so I immediately cancelled my FOX order and ordered Icons instead for the rear set up, assuming that the mismatch in shock style may upset the balance of the truck while hitting the trails at high speed.. The FOX order did not cancel in time, I got them, and the company promised to refund the money while letting me keep the FOX shocks because they will not take them back.. NOW, I have free Fox shocks just were just installed today, and the ICons are on a two week back order....


QUESTION.. Does anyone know if there is a negative effect in running Digressive shocks in the front and Progressive in the rear? Can it upset the balance? Soon enough I will put them to a good test, I am just not sure if I should cancel to order for the Icons as they are more expensive than the FOX shocks (especially when the FOXs are free) and I see no evidence that the Icons are better. My only though was I better run the same type of shock all the way around, i.e. digressive shocks..

By the way, so far the set up feels great!! Large curbs feel like small speed bumps.. Just got them installed today so no rear offroad testing other than some articulation tests and definitely see and improvement

If anyone has experience with this, please chime in!
Thanks!

 

[fromLRtoT4R]

no one knows ha?

 

[Stinger1967]

I heard Icons were awesome from a buddy who has on a 2014 4Runner.

 

[mrpurplepenguin]

I'll preface this by saying I don't have a bunch of real world experience here, just a bit of book knowledge and setting up/tuning my track bike suspension. Just the same, I'll put in my 2 cents...

First and most important, if you like the feel of it and think it's responding well, don't let a graph or some numbers on a page tell you you're wrong; a driver on bad suspension that feels proper to them is far better than the best suspension setup being driven by someone who doesn't like the way it handles.

Second, make sure you exercise your suspension at a range of velocities (not vehicle velocity but suspension velocity; try bigger/steeper hits vs. shallower ones at the same speed) to get a proper feel for how it's responding.

It's hard to make a quantitative assessment of your setup without going into a lot of numbers and charts, but you should notice the front end gets mushier and starts blowing through its travel for faster hits while the back gets stiffer (digressive vs progressive). This might be fine at the speeds you're taking bumps, but it will get less ideal the faster the suspension is working (which still might be way faster than you'll ever make it work, so it could never become a problem).

So...yes, having the front/rear mismatched is an imbalanced setup and could be bad. But if you like the feel of it at all sizes and speeds of bumps you're hitting, it's fine for you.

As an aside, where did you order your Fox shocks from? That's an impressive deal they gave you!

 

[cpark_12]

What Fox shocks did you go with?

 

[Morphyne]

I would like to know what the difference between progressive and digressive is. All greek to me.

 

[fromLRtoT4R]

First, mrpurplepenguin, thank you for that write up.. That is pretty much was I was thinking.. I live in So AZ and we have no shortage of desert and trails around here.. Were talking about bumps, ruts, washouts, pretty narly trails.. stock run through one of the trails was pretty sad.. had to slow down to 5-10 mph in large sections of a trail bec suspension could not keep up.. I am one of those people who gets their thrill from going fast, pretty much all the time.. So far I am liking this set up very much.. The toytec rear spring are pretty soft and the whole set up feels pretty even but that is just going over curbs and small street bumps for now.. will definitely try to put it through some feel in the seat testing as soon as I can.. I just worry about what happens when I push a 10mph section to 25 or 35 or more.. we shall see I guess!!

the shocks are FOX 2.0 IFP Smooth Body

I got them at autoanything.com I buy a lot from them for my dealership so I get 20 and 22% discounts all the time

I just would really love an explanation of what happens to these shocks (bilsteins 6112 or fox rears or icon rears) when the frequency of suspension bounce goes way up along with suspension travel.. because firm or mushy I understand, but what that does for the tire leaving the ground could be a different story completely

 

[GX4SEVEND]

This in no way is meant to sounds rude, but I think you're over thinking this for a 2" lift spring. I have ran icon for a number of years now and love them. My buddy has the Fox's and loves them as well.

Either way I think you'll be way happier than stock.

 

[mrpurplepenguin]

I just would really love an explanation of what happens to these shocks (bilsteins 6112 or fox rears or icon rears) when the frequency of suspension bounce goes way up along with suspension travel.. because firm or mushy I understand, but what that does for the tire leaving the ground could be a different story completely

OK, cool. I wasn't sure how in-depth to go at first, but that helps clarify your question a bit more.

So, I assume that it's the compression valving on these shocks that's progressive/regressive and not the rebound circuit - correct me if I'm wrong!

In short, a digressive compression damping curve will feel firmer and more controlled (or even a bit harsh) at lower suspension velocity, then become more plush and will "soak up" faster hits - which lets you run though slower terrain with a better feeling of control, or larger terrain at faster speeds. The downside: since there's less resistance at higher speeds, it's easier to launch a wheel off the ground on bigger/faster bumps (the spring can't push the wheel back down quickly enough to maintain contact when it's also fighting upward inertia), which can make it feel "floaty" or a bit vague (ever drive a washboarded dirt road too quickly?). This can lead to "packing", where your suspension squats more on each bump (if the bumps are in quick succession, like a washboarded road) because between bumps the rebound damping isn't letting it relax as much as it compresses on each bump. Additionally, you're more likely to blow through the full stroke of the shock on fast hits that are taller than your suspension travel - hello bump stops and a very harsh ride!

Progressive compression damping will give you a more "floaty" feel over smaller stuff (so you can travel faster over it, but it'll feel a little loose), but then firm up as the bumps get steeper. You're less likely to lose wheel contact with the ground on the backside of bumps (not as much upwards inertia in the wheel), but you'll feel the car buck more - which could pull the wheel off the ground by launching the chassis upwards. You'll also feel a harsher ride that will limit your top speed (more fast = even harsher). If you're going fast enough over bumps taller than your suspension travel that you're becoming airborne, progressive valving is for you - you won't slam into the bump stops when you land.

Finally, you mentioned not only increasing suspension velocity but suspension travel as well - there's no difference between progressive/digressive for different travel lengths. All that matters to the damping curve is velocity, not position. *Shocks are usually setup with a small air volume that compresses and becomes stiffer near full stroke to give some progressive spring action when you're close to bottoming out, and I'm sure Fox/Icon/etc each have their own differences there. I can't speak to the particulars of that though, but each will feel different as you approach full stroke and start to interact with the bump stops.

I can't speak to what the damping profile looks like for each of those shocks, but that's the general "seat of the pants" difference. You might still be well within the velocity range where everything is pretty balanced with the front and rear mismatched, but the differences will become more apparent at faster suspension velocities - maybe way faster than you'll ever want to go. I'll conclude by reiterating what I started with before - if it feels right for you, don't change it to make it right on paper.

Hope that helps!

 

[mrpurplepenguin]

I would like to know what the difference between progressive and digressive is. All greek to me.

Just so everyone's on the same page, I'm assuming we're talking about compression damping of the shocks in my above comments, but to clarify:

Progressive damping is when the damping force increases exponentially (the shock gets stiffer) as suspension speed increases linearly, due to either steeper bumps at the same speed (think of running over a square faced curb vs. running over a round speed bump) or the same bumps at faster speeds (think running over a speed bump at 5 mph vs. 25 mph).

Digressive damping is when the damping force decreases (the shock gets softer) as suspension speed increases. (Typically it actually becomes stiffer for a bit at low speeds then softens up as speed increases past that point).

Right in the middle between the two is linear damping, where the damping force increases linearly as suspension speed increases linearly.

Hope that helps!

 

[cpark_12]

I've had the superflex paired with the fox 2.0. They ride great on the street and great off road. On dirt roads though, they're stiff! The back of my truck bounced around like a pick up if I went too fast down them.

Just my 2 cents!

 

[fromLRtoT4R]

So, I assume that it's the compression valving on these shocks that's progressive/regressive and not the rebound circuit - correct me if I'm wrong!

Thanks again for the great explanation.. I am not sure if the special valving is for compression stroke only, and not the rebound.. I kind of assumed it was for both, so this is a new thought to me.. I wonder if anyone can verify.. When you look up info, it just says progressive or digressive and claim that each is superior.. go figure..


I know that both are a 1000x better than stock, I just don't want to upset the balance, which is starting to become clear to me now that I may have done that and will notice on a fast dirt trail.. It almost seems to me that progressives are better for jumping (like the Ford Raptors you always see online) where as digressives are better if you want to hit a dirt road at paved road speed and imagine that your in a lincoln town car..

I imagine either one will give me enough control as I am not a professional rally driver anyway..

It also seems to me that if I dump a bunch of weight in the back of the truck, perhaps that would be a good reason to offset the balance of shock valving, but not at normal weight..

I just thought that because the toytec springs are relatively soft, the fox shock may compliment them very well even though I am running a digressive system in the front.. I am thinking now that was not a good idea.. I will keep my order for the icons, and will try to get some impressions for both for all you who may be interested...

Aside from all of this, the very limited dirt driving I have done so far (on the way and back from work) feels amazing.. But I do notice a bit more bucking in the rear like you mentioned

 

[fromLRtoT4R]

I've had the superflex paired with the fox 2.0. They ride great on the street and great off road. On dirt roads though, they're stiff! The back of my truck bounced around like a pick up if I went too fast down them.

Just my 2 cents!

I believe you.. Thats kind of what I want to avoid

 

[Firstoneman]

Thanks again for the great explanation.. I am not sure if the special valving is for compression stroke only, and not the rebound.. I kind of assumed it was for both, so this is a new thought to me.. I wonder if anyone can verify.. When you look up info, it just says progressive or digressive and claim that each is superior.. go figure..

I just thought that because the toytec springs are relatively soft, the fox shock may compliment them very well even though I am running a digressive system in the front.. I am thinking now that was not a good idea.. I will keep my order for the icons, and will try to get some impressions for both for all you who may be interested...

Aside from all of this, the very limited dirt driving I have done so far (on the way and back from work) feels amazing.. But I do notice a bit more bucking in the rear like you mentioned

I don't know if you are still around...but did you ever try out the ICONS in the end? How did it go?

thanks.
D