IFS conversion for 100 series (1 Viewer)

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So I am sure this has been discussed but could not find a thread.

With the ability to do so many major mods, like SAS, engine swaps etc.. How hard would it be to fab up a smiliar set up to the 200 series Coil over front suspension to replace the torsion bars in the 100?

What would you gain in travel?

I wonder just how much different the 200 series frame is to the 100 series and if there are components that could be ordered as OEM to help with the conversion.

Is it only a matter of welding a larger housing for the Coil over to mount to?

Christo must have looked at this? Are there new 100s in other countries that have Coil over vs. torsion bars?
 
What is your goal with the coils vs the torsion bars? I think the decision was predicated on space allocation. At the end of the day we have about as much travel as the CV's want to take.
 
What is your goal with the coils vs the torsion bars? I think the decision was predicated on space allocation. At the end of the day we have about as much travel as the CV's want to take.

The 100s must use similar Toyota components like the 4runners, Tacos and FJCs. If anything I would think our CVs would be slightly beefer than the ones for these smaller rigs.

Goal would be to gain more travel, potentially more adjustability for larger tires without maxing out suspension.
 
The 'beefiness' is related to torque. Impingement is impingement. The CV's can only flex so much.

You're correct that there could be a potential for other gains (tire size, ride quality, alignment?) but at what cost and what gain?

For an IFS setup, it's not a bad system. But it is IFS and will always have less ultimate potential than SFA. If I were going to invest a bunch of R&D and shop time I'd go for the SFA but that's just me. Too much work to convert to coil with too little gain.
 

Thanks for the heads up on these.

I saw a lot of comments that the shock mount was not strong enough on the lower a-arm. I am not sure I agree with that. They look exactly the same as the 4runner and FJC lower a-arm mounts.

The travel and ride would be worth a try, in my opinion. This is a worthy mod.

The 100 is very similar, just bigger than the FJC and 4runner models. If you are ever curious if something is possible or not, it might be helpful to peek over in the blue room (FJC forum) to see if it has been done already.

The FJC crowd has done just about everything being considered or done here..

We did UCAs, Lower links, bigger tires, body mount chops, all that stuff back in 07-present. So lots of experience, pics, photos.. etc..

One thing that is a bit different there vs here is the diff drop. Not too many over there bothered with it at all, where here it is a bit of a standard mod and there have not been significant CV failures because of skipping this step, that I remember.

Anyway, I really would like to test a set of Coil overs for the 100. I had Icons on my FJC/4runner and they were a great mod to add to the vehicle.

I wonder if there is a weight benefit to dumping the TBars vs the coilovers?

Even if this was nothing more than a comparable mod to the existing set up, if I was in the manufacturing business within our hobby, I would build them and happily watch them fly off the shelf.. These are popular in the other vehicles and look cool. One of those mods you can do and look at it every day.

These typically retail for close to 1000.00 for a set, so I wonder if the margin is beneficial also.
 
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I agree that coilovers would be a significant upgrade. I've ridden in a couple FJCruisers and they "feel" so much smoother and "flexier" on the trail than the Series 100 does. I know that's not scientific but I'm interested in seeing where this goes in the $'s spent vs. performance gained.
 
Do recall however that the t-bar hi-lux trucks have a reputation for holding up for the rest of the (rough and tumble) world better than the coil-over based Tacos/$-runners/FJC's etc.

IMFUO:
All you're talking about is using a different spring style. I don't see many advantages other than perhaps the ability to tune through coil bind and progressive coils. Can a T-bar be made progressive?

There are no travel or damping advantages to be had. No matter how beef the CV you still can only use it at a given maximum angle.

I think a major hurdle is the size of coil required vs the space available inside the UCA.

If you want a 100 that handles like an FJC you need to get the weight down, way, way, down.
 
IMO the 100 already rides pretty amazingly comfortable on the trail and flexes plenty for a 6,000+ lb IFS truck. If you were to drop $3-4k on suspension mods, $3-4k on lockers/gears, $3-4k on bumpers and sliders, then the added cost for tires, roof rack, drawers and fridges..it all just gets so expensive for marginal increases I'm not sure it makes much sense. I for one would rather start off with a platform with solid axles, lockers, 4 to 1 tcase, etc. (yes I mean a 4 door Rubicon JK) instead of spending crazy money to get this thing to perform like something it's not.

My personal dream would be to take a 07 LC with crazy low miles bone stock, do an SAS, build it into a pop top camper, put it on 35-37" tires and enjoy it for decades to come with 90% of the JKs ability with 200% of the comfort. As it is right now, I'm trying to maximize what the 100 platform will do with a modest budget and appreciate it for what it is.
 
I just spoke with Mark from MetalTech last week on this very topic.... he is looking for a 100 to graft the FJ Cruiser IFS into. He said that he has the measurements and it would fit. It would be a one off project.

In terms of CV we spoke about hybrids with 100's on the inside to meet the differential.
 
There's a lot going on here...

1) reworked spindle... restores UCA working angle and R&P working angle
2) Lower control arm drop bracket
3) shock mount relocated with coil over springs

Road testing.... I don't know if this is the same vehicle but the suspension set-up is similar.
https://www.youtube.com/watch?v=Z3NGxu8LgmQ

The rest of
pictures.


F34-12-185_bbe99.750.jpg


F34-12-062_6c564.750.jpg


F34-12-068_dea9f.750.jpg
 
I just spoke with Mark from MetalTech last week on this very topic.... he is looking for a 100 to graft the FJ Cruiser IFS into. He said that he has the measurements and it would fit. It would be a one off project. In terms of CV we spoke about hybrids with 100's on the inside to meet the differential.

Here is where it gets expensive. Custom CVs to match up.
 
Do recall however that the t-bar hi-lux trucks have a reputation for holding up for the rest of the (rough and tumble) world better than the coil-over based Tacos/$-runners/FJC's etc.

IMFUO:
All you're talking about is using a different spring style. I don't see many advantages other than perhaps the ability to tune through coil bind and progressive coils. Can a T-bar be made progressive?

There are no travel or damping advantages to be had. No matter how beef the CV you still can only use it at a given maximum angle.

I think a major hurdle is the size of coil required vs the space available inside the UCA.

If you want a 100 that handles like an FJC you need to get the weight down, way, way, down.

I think there are travel advantages. You are really limited on how far you can raise the torsion bar and how it relates to down travel/droop. I don't have the numbers but I am pretty sure you could get close to 3 more inches downward travel with a coil over set up vs our TB. I could be wrong.

If I am right, for 1000.00 cost, I would be willing to gain 2-3 inches more travel.

You would only be in these extremes for moments at a time and should not kill the CV.
 
No way it will ever happen for 1k. Just look how much UCA's cost alone. There are a lot of other variables as hoser noted.

Aftermarket uca
Aftermarket Lca
Long travel CV
New shocks
Fender modifications
Etc....

Would be cool to see, but not going to happen for 1k and be reliable.
 
I think there are travel advantages. You are really limited on how far you can raise the torsion bar and how it relates to down travel/droop. I don't have the numbers but I am pretty sure you could get close to 3 more inches downward travel with a coil over set up vs our TB. I could be wrong.

If I am right, for 1000.00 cost, I would be willing to gain 2-3 inches more travel.

You would only be in these extremes for moments at a time and should not kill the CV.


But the torsion bar does not limit down travel at all. The shock limits the travel to keep the UCA from binding and the CV from being destroyed.

The long travel kits are wide to limit CV deflection.

A pair of good shocks to base the system on will cost 800 - 1300 just to get started.

Where does the 3" of additional down travel number come from?
 
All that stuff is overkill and not really needed, imo.

I am pretty sure you would just need to mod the top mount and install the coil over. There is also one space bar that is installed for clearance of a sway bar on the FJC/4runner.

Or design a spring that would be stiff enough and narrow enough to fit in the current space provided.

Look up Coil over pricing for the the FJC and 4runners, $1,000.00 for ToyTec or ICONS.. So for 100 series is needed to be beefer for weight, $1200.00??
 
But the torsion bar does not limit down travel at all. The shock limits the travel to keep the UCA from binding and the CV from being destroyed.

The long travel kits are wide to limit CV deflection.

A pair of good shocks to base the system on will cost 800 - 1300 just to get started.

Where does the 3" of additional down travel number come from?

My understanding was that if you crank the torsion bar to far, it does limit down travel, maybe I have that wrong.
 
That just looks like an upgraded coilover for the FJC not a big performance upgrade. We can bolt on $1k up front and get about an extra inch of travel, but that is maxing out the CV. Sounds like you are basically just envisioning a longer shock, that won't work without having other custom parts to be able to use the longer shock. You need to change more than just the spring style to get that 3 inches you are thinking of.
 
Could we drop the front diff another .75"s? The limiting CV angle is droop, right? The never reach that extreme of an angle upward.

You'll give up some front ground clearance but with 35"s tires and IFS you have better front ground clearance than a solid axle anyway.
 

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