Torsion bar vs Coil Over travel? (1 Viewer)

[jLB]

Interesting video, that tends to illustrate some of what limits the travel of the 100 series IFS:



Shock length.
(UCA hitting shock.)
(Ball Joint binding.)
UCA hitting mount.
(CV axle binding.)

None of it really seems to have anything to do with the alleged physical format issues of the spring being “torsion bar” vs “coil over”.

 

[Roosevelt T]

A spring up front would allow us to customize spring rate at x ride height for our different applications (and weight, etc). This would be very nice (IMO). I don't think anyone ever claimed it inherently effect travel

F1 cars use torsion bars, albeit mostly because of packaging and weight. There's nothing inherently wrong with them.

/Cue the guys with 80's who never shut up about solid axles and torsion bars.

 

[jLB]

A spring up front would allow us to customize spring rate at x ride height for our different applications (and weight, etc). This would be very nice (IMO).

It won't inherently effect travel.

I don’t disagree that the spring rates are very limited by the torsion bars that are available, but it seems that the common “party line” around here is that “if I could only change to a coil over, I could get so much more travel than a torsion bar”, isn’t exactly accurate.

 

[GTV]

Very interesting. Here's part two:


This helps to answer the question I recently posted here. I'll have to unbolt my front AHC "shocks" next time I'm in there to see if there are similar results.

 

[OwnerCS]

Interesting video, that tends to illustrate some of what limits the travel of the 100 series IFS:



Shock length.
(UCA hitting shock.)
(Ball Joint binding.)
UCA hitting mount.
(CV axle binding.)

None of it really seems to have anything to do with the alleged physical format issues of the spring being “torsion bar” vs “coil over”.

Just a quick glance. He is correct that down travel is limited by the SPC control arm's contact with the frame mount. The limitation will be there unless there is a completely different design for the UCA. Running Dobinsons IMS LT, down travel is limited by the SPC UCA. That's all I have to say for now.

 

[AlpineAccess]

I'd prefer coils just for ease of maintenance/removal; and having more spring rate options.

I have SPC uppers and when @bgolf247 and I swapped tough dog shocks he did find the bigger shock (54mm vs 45?) gave an extra inch of droop by shifting the limiting to the UCA vs the shock.

 

[Roosevelt T]

I don’t disagree that the spring rates are very limited by the torsion bars that are available, but it seems that the common “party line” around here is that “if I could only change to a coil over, I could get so much more travel than a torsion bar”, isn’t exactly accurate.

I guess I haven't seen this comment in a long time, but I believe you that its here.

And yea, its not accurate at all.

 

[krice118]

I like Torsion Bars. They make wheeling more interesting. Honestly a lifted 100 with 33s is pretty damn capable - its nice to lift a front tire and have a challenge once in a while....

 

[jLB]

I guess I haven't seen this comment in a long time, but I believe you that its here.

And yea, its not accurate at all.

I’d already done similar experiments, and come to similar conclusions, when we started building my son’s vehicle, but I wasn’t smart enough to record my experiments and post them on the internet.

Just a quick glance. He is correct that down travel is limited by the SPC control arm's contact with the frame mount. The limitation will be there unless there is a completely different design for the UCA. Running Dobinsons IMS LT, down travel is limited by the SPC UCA. That's all I have to say for now.

My primary experimentation with the front extended length IMS, was on our 99 LX. I have different aftermarket UCAs, but I remember there being a slight gap between the UCA and mount, at a static full droop. Not to say that the UCA couldn’t make contact with the mount under a more dynamic situation, where the shock (and/or UCA) bushings were deformed.

Maybe it’s an excuse for me to go play with a floor jack, and compare the vehicles in the driveway again…

 

[OwnerCS]

I’d already done similar experiments, and come to similar conclusions, when we started building my son’s vehicle, but I wasn’t smart enough to record my experiments and post them on the internet.



My primary experimentation with the front extended length IMS, was on our 99 LX. I have different aftermarket UCAs, but I remember there being a slight gap between the UCA and mount, at a static full droop. Not to say that the UCA couldn’t make contact with the mount under a more dynamic situation, where the shock (and/or UCA) bushings were deformed.

Maybe it’s an excuse for me to go play with a floor jack, and compare the vehicles in the driveway again…

Mine get fully slammed -- often. No complaints.