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Corbet
06-29-2010, 06:56 PM
What limits downward travel on an 80 series suspension system? The shock?

corsair23
06-29-2010, 06:58 PM
What limits downward travel on an 80 series suspension system? The shock?

Hopefully not if you have the suspension set up right :)

I'd think it would be the bump stops (inside the coil typically unless you've got a different setup like Rami's)...They'll limit the up travel on one side and the down travel on the opposite side. I'm by no means a suspension expert though so the smarter guys for sure will chime in :hill:

Corbet
06-29-2010, 07:05 PM
yes bump stop for up travel but what for the down travel?

Bikeman
06-29-2010, 08:35 PM
Swaybars then shocks.

AxleIke
06-29-2010, 10:41 PM
Which end? In the front its the radius arms. Rear, I imagine bikeman hit the nail on the head.

Uncle Ben
06-29-2010, 10:47 PM
Which end? In the front its the radius arms. Rear, I imagine bikeman hit the nail on the head.

Brake lines! :eek::lmao::lmao::lmao: Bikeman is correct.

AxleIke
06-29-2010, 10:51 PM
Brake lines! :eek::lmao::lmao::lmao: Bikeman is correct.

IIRC, ActionJackson was able to get a fair bit more flex out of the front by removing one of the bolts on the radius arms so it functioned a bit more like a 3link front

Uncle Ben
06-29-2010, 10:53 PM
IIRC, ActionJackson was able to get a fair bit more flex out of the front by removing one of the bolts on the radius arms so it functioned a bit more like a 3link front

Ben Lowry in Greeley played with that too! He put a pin in the drivers side while street driving then he would remove it on the trail. Quite a bit more down travel was produced.

AxleIke
06-29-2010, 10:58 PM
Ah. Didn't know that.

Corbet
06-30-2010, 09:21 AM
Brake lines! :eek::lmao::lmao::lmao: Bikeman is correct.

Kevin, are you saying Bikeman is correct in that its sway bars then shocks on both ends? Or ar the radius arms the limiting factor in the front?

Uncle Ben
06-30-2010, 09:45 AM
Kevin, are you saying Bikeman is correct in that its sway bars then shocks on both ends? Or ar the radius arms the limiting factor in the front?

Both! The front radius arms bind due to the 4 mounting points on two arms thus limiting the opposing travel arcs. The rear sway bar definatly does it's job and adds substantial resistance to opposing arcs of the rear wheel and the shocks will stop droop a few degrees prior to the coil springs unseating. Many guys use Bilstien shocks that will add another 1+" droop over the OME's. The sway bars on an 80 are very well balanced into the system and off-roading is not adversely affected by their attachment. If you're one of those guy's who have to stretch out on an RTI ramp then yes, the sway bars will increase numbers if removed.

Beater
06-30-2010, 11:22 AM
there are many factors here. radius arm bushing flex is a large portion of it, as well as geometery. also balance front to rear plays as well. If the front doesn't force the rear and vice versa, you will have issues.

I could max out 12" shocks easy on my 80.

corsair23
06-30-2010, 12:34 PM
Ok...all this has me wondering what is the true purpose of bump stops then?

I understand that all of the other things mentioned (control arms, sway bars, etc.) will limit axle articulation. Given that, are the bump stops' primary purpose to limit damage should you exceed the other components "limits" during say a hard hit?

If I install bump stops that sit 1" off my axles then they would limit articulation well before anything else did right? If the front right can only go up 1" then the left front can't drop any further than the opposite bump stop would allow it to given that the axle is solid.

So is the goal to have bump stops that are right at, or just beyond, the limits of everything else?

Uncle Ben
06-30-2010, 01:16 PM
Ok...all this has me wondering what is the true purpose of bump stops then?

I understand that all of the other things mentioned (control arms, sway bars, etc.) will limit axle articulation. Given that, are the bump stops' primary purpose to limit damage should you exceed the other components "limits" during say a hard hit?

If I install bump stops that sit 1" off my axles then they would limit articulation well before anything else did right? If the front right can only go up 1" then the left front can't drop any further than the opposite bump stop would allow it to given that the axle is solid.

So is the goal to have bump stops that are right at, or just beyond, the limits of everything else?

Bump stops only limit compression. Corbets question was what limits downtravel (droop).

corsair23
06-30-2010, 01:30 PM
Bump stops only limit compression. Corbets question was what limits downtravel (droop).

Understood...But it just makes sense to me that with a SA setup, what limits compression/up-travel on one end will also limit down-travel on the opposite end...I'm guessing that given bump stop placement, maybe it isn't an "even" limiting factor (i.e. 5" of up-travel doesn't translate into 5" of down-travel on the other end)...

Probably a good thing I don't design suspensions :o

Beater
06-30-2010, 02:23 PM
your thoughts would be accurate if it were a fixed pivot system. due to the binding nature of the components and the 4/6 point mounting of the radius arms.

Corbet
06-30-2010, 05:11 PM
Good discussion going.

But removing articulation from the equation what stops droop or drop independent of articulatioin. For example. Up on a shop lift what stops the axle from dropping.

Seems to me sway bars, based on past posts.

Tch2fly
06-30-2010, 06:47 PM
Good discussion going.

But removing articulation from the equation what stops droop or drop independent of articulatioin. For example. Up on a shop lift what stops the axle from dropping.

Seems to me sway bars, based on past posts.

On a hoist it is the shocks that limit the drop.
When the axle drops straight down the sway bar would have very little impact, they ae really designed to maintian a more level stance when cornering and preventing excessive body roll during evasive manuevers. The limiting effects on articulation occur when the axle ends move in opposite directions.

coax
06-30-2010, 07:40 PM
Good discussion going.
x2. I was wondering this myself. So the shocks must be fairly stout in construction then to be able to lift a wheel on a fully loaded truck then?

Corbet
06-30-2010, 09:15 PM
So where I am going with this....

I am getting ready to install a 2" lift in Aug. I have made arrangements to aquire the Iron Man lift given out during the CM10 raffle dinner. I know what some of you may be thinking. Hell must be freezing over Corbet is lifting his truck :D

So along with the 2" lift I will be moving up to 35/315 tires. So a pair of bump stop drops will also be required. This will take away some of my up travel so my thoughts are to possibly add some spacers on top of the springs to regain some of the travel by spacing down the suspension a little. Now I need to worry a little about the max length of the shocks. Iron Man says the shocks are good for 3" of lift. So I'm thinking I'm good but wanted a stronger understanding of what is going to limit the bottom end of the 80's suspension travel.

Continue discussion...:beer:

wesintl
06-30-2010, 10:00 PM
why that much tire with 2"?

nakman
06-30-2010, 10:19 PM
x2. I was wondering this myself. So the shocks must be fairly stout in construction then to be able to lift a wheel on a fully loaded truck then?

I forget the guy's name, but we had an ARB rep come present to us one night and review the OME shocks, Billstein shocks, several ARB products.. the name will come to me in a minute. But I remember asking point blank if it was alright to use OME shocks as limiters and yes, they'll hold up to it fine. Maybe if you're taking them off a bunch of jumps then you'll wear them out, but normal wheeling articulation is normal use.


Corbet what kind of shocks are you getting? I've run just about every ride height, but all on the OME setups.. http://www.risingsun4x4club.org/uploads/smileys/popcorn.gif

AxleIke
06-30-2010, 10:35 PM
So where I am going with this....

I am getting ready to install a 2" lift in Aug. I have made arrangements to aquire the Iron Man lift given out during the CM10 raffle dinner. I know what some of you may be thinking. Hell must be freezing over Corbet is lifting his truck :D

So along with the 2" lift I will be moving up to 35/315 tires. So a pair of bump stop drops will also be required. This will take away some of my up travel so my thoughts are to possibly add some spacers on top of the springs to regain some of the travel by spacing down the suspension a little. Now I need to worry a little about the max length of the shocks. Iron Man says the shocks are good for 3" of lift. So I'm thinking I'm good but wanted a stronger understanding of what is going to limit the bottom end of the 80's suspension travel.

Continue discussion...:beer:

I'm lost.

Why do you need to move the bumpstops at all? Leave them stock, and retain as much travel as you can.

Uncle Ben
06-30-2010, 10:46 PM
So where I am going with this....

I am getting ready to install a 2" lift in Aug. I have made arrangements to aquire the Iron Man lift given out during the CM10 raffle dinner. I know what some of you may be thinking. Hell must be freezing over Corbet is lifting his truck :D

So along with the 2" lift I will be moving up to 35/315 tires. So a pair of bump stop drops will also be required. This will take away some of my up travel so my thoughts are to possibly add some spacers on top of the springs to regain some of the travel by spacing down the suspension a little. Now I need to worry a little about the max length of the shocks. Iron Man says the shocks are good for 3" of lift. So I'm thinking I'm good but wanted a stronger understanding of what is going to limit the bottom end of the 80's suspension travel.

Continue discussion...:beer:



You doing gears too? 35's on an 80 start that expensive slippery slope thang!

Corbet
06-30-2010, 11:07 PM
why that much tire with 2"?

Why not? I'm running 295's now with stock suspension. With a lift I must need more right? :hill: I'd stick 37's under her if I could afford a 4" lift.


You doing gears too? 35's on an 80 start that expensive slippery slope thang!

Gears (4.88) most likely next mod but not right away.

Why do you need to move the bumpstops at all? Leave them stock, and retain as much travel as you can.

I'm rubbing my 295's now. 315 or 35" will definitely rub with full spring compression. I also need to leave room for chains in the winter.

Corbet
06-30-2010, 11:11 PM
Corbet what kind of shocks are you getting? I've run just about every ride height, but all on the OME setups.. http://www.risingsun4x4club.org/uploads/smileys/popcorn.gif

Iron Man foam units for the 2" kit. http://store.camel4x4.com/product/OVERVIEW_FOAMCELL.html

Tch2fly
07-01-2010, 09:25 AM
IMO you are good to go.
At the moment I have about 4" of lift and I am still running the "standard" length OME shocks that came originally with my 2.5" lift. I know that this MAY limit the droop but I don't see it as a big deal .... I have not any issues on the trails (I ran this setup on Rubicon and all over Moab).
I realize that I won't score very high on a ramp but considering the other suspension limitations
of an 80 Series in the dynamic environment of a trail, I don't see that as a problem.

AxleIke
07-01-2010, 10:48 AM
I'm rubbing my 295's now. 315 or 35" will definitely rub with full spring compression. I also need to leave room for chains in the winter.

I still think limiting the flex that much more isn't worth it. Just cut out what you rub on. Likely all you are rubing is a pinch weld or body seam. You have a nice welder now, just cut it out and weld in a patch and voila, whatever size tire you want.

Corbet
07-01-2010, 11:02 AM
I rub the top of the inner fender (plastic part) right now both front and back. Funny thing is I never used to rum up front until this year? Maybe my bumpstops are wearing and getting extra soft?

I'll install the kit then take a look. I'll be running my 295 TG until winter when I plan to get a set of studded GY Duratrac's in 315 unless I change my mind by then.

Uncle Ben
07-01-2010, 12:06 PM
I still think limiting the flex that much more isn't worth it. Just cut out what you rub on. Likely all you are rubing is a pinch weld or body seam. You have a nice welder now, just cut it out and weld in a patch and voila, whatever size tire you want.

Not a mini! 80's rear tubs are narrow and the more articulation you get the more the tire will rub on the inner fenderwell. Fronts usually can be calmed with the removal of one inner fender well bolt. I'm running 4" bump stops on the back of mine which seems to be perfect.

Uncle Ben
07-01-2010, 12:10 PM
IMO you are good to go.
At the moment I have about 4" of lift and I am still running the "standard" length OME shocks that came originally with my 2.5" lift. I know that this MAY limit the droop but I don't see it as a big deal .... I have not any issues on the trails (I ran this setup on Rubicon and all over Moab).
I realize that I won't score very high on a ramp but considering the other suspension limitations
of an 80 Series in the dynamic environment of a trail, I don't see that as a problem.

Ramp's are for testing and showing off but have no bearing on how a vehicle wheels! If I remember right your mall Cruiser did just fine in real world Rubicon environment!

corsair23
07-01-2010, 01:57 PM
Ramp's are for testing and showing off but have no bearing on how a vehicle wheels!

I thought ramps were just used so you could check the underside of your Hummer :confused: :hill:

f2cZXAie4lU

AxleIke
07-01-2010, 02:28 PM
Not a mini! 80's rear tubs are narrow and the more articulation you get the more the tire will rub on the inner fenderwell. Fronts usually can be calmed with the removal of one inner fender well bolt. I'm running 4" bump stops on the back of mine which seems to be perfect.

Not sure what you mean there. It doesn't really matter what vehicle it is. If it rubs, cut it.

wesintl
07-01-2010, 02:37 PM
If it rubs, cut it.
OMG :eek: :eek: :eek:

AxleIke
07-01-2010, 03:17 PM
OMG :eek: :eek: :eek:

Hmm...I see I should have clarified :D

corsair23
07-01-2010, 04:46 PM
If it rubs, cut it.

Sig worthy quote right there....:lmao:

Uncle Ben
07-01-2010, 05:23 PM
Sig worthy quote right there....:lmao:

Got it! :lmao:

coax
07-01-2010, 09:48 PM
So where I am going with this....

I am getting ready to install a 2" lift in Aug.
Continue discussion...:beer:

Was just reading through this old thread in Mud. Only somewhat related to the original question, but its got some good discussion IMO and might be helpful.

http://forum.ih8mud.com/80-series-tech/93169-so-what-point-do-you-need-go-l-shocks.html

I think in the very near future I'll be going to L's in the front, as it seems to ride quite high with no bumper on there. Not sure what the "magic" number or ratio is in terms of extension travel for safety, but I'm probably 3+ inches away from it right now.

bigbluefj
07-02-2010, 04:01 AM
I thought ramps were just used so you could check the underside of your Hummer :confused: :hill:

f2cZXAie4lU

Thats an old one, i remember that day he also had a big 40 all done up also...

Uncle Ben
07-02-2010, 07:28 AM
I thought ramps were just used so you could check the underside of your Hummer :confused: :hill:

f2cZXAie4lU

http://www.hayabusa.org/forum/attachments/general-bike-related-topics/171930d1262829012-crazy-looking-batman-riding-suit-repost.jpg

Nay
07-02-2010, 10:59 PM
Not sure what you mean there. It doesn't really matter what vehicle it is. If it rubs, cut it.

You aren't thinking about this correctly (ignoring the last sentence :D). With much larger tires, you need to space down the entire suspension travel. Longer shocks, or shocks used with pin to eye adapters, will reduce available up travel because you have less available compression travel.

Longer bumpstops are needed to protect the shocks and have the additional benefit of stopping up travel before the tire makes contact.

If you look at my suspension, I have a 3.5" lift with a 10" travel shock. I have 2" bumpstop drops up front (although they are not needed for articulation, just there for pure impact compression) and 2.5" in the rear, 37" tires.

My shock travel is balanced almost exactly 50% up and 50% down. I have not lost any travel as the bumpstops protect about the last 3/4" of shock up travel and you have to account for some degree of bumpstop compression, and my suspension is properly balanced to allow max articulation across the range of motion before one end is either hanging on a shock or up against a bumpstop rather than the entire system moving freely.

If I were to decide to cut the body to preserve original up travel (no downward spacing of shock travel) I'd basically have about 7" up and 3" down, which is why you see OME users go to L shocks to space down their travel at 3"+ lifts. This unbalance is undesirable for rock crawling, although you might like it for high speed overland travel where you are hitting big bumps at speed - you would also probably keep smaller tires for this usage and not have the contact issues.

The bottom line is you need to look at where your shocks actually fully compress and ensure your bumpstops are protecting the shocks. If at full compression you have tire/body contact, spacing the shock travel down while ensuring you keep a good compression/droop balance is the goal.

This is easily accomplished on the 80, and using eye adapters without increasing shock travel will help keep the rear tires from angling so much into the wheel wheels. I have no issues picking up rear tires and have avoided the issues that come with adding too much travel. Plus, the front of the 80 can't use any extra travel anyway, so front to rear balance should always be a consideration.

This is why I wheel with my front swaybar removed and rear attached. It is well balanced for such a big pig.

No substitute for measuring on your rig - you can tune from there :hill:

AxleIke
07-02-2010, 11:47 PM
You aren't thinking about this correctly (ignoring the last sentence :D). With much larger tires, you need to space down the entire suspension travel. Longer shocks, or shocks used with pin to eye adapters, will reduce available up travel because you have less available compression travel.

Longer bumpstops are needed to protect the shocks and have the additional benefit of stopping up travel before the tire makes contact.

If you look at my suspension, I have a 3.5" lift with a 10" travel shock. I have 2" bumpstop drops up front (although they are not needed for articulation, just there for pure impact compression) and 2.5" in the rear, 37" tires.

My shock travel is balanced almost exactly 50% up and 50% down. I have not lost any travel as the bumpstops protect about the last 3/4" of shock up travel and you have to account for some degree of bumpstop compression, and my suspension is properly balanced to allow max articulation across the range of motion before one end is either hanging on a shock or up against a bumpstop rather than the entire system moving freely.

If I were to decide to cut the body to preserve original up travel (no downward spacing of shock travel) I'd basically have about 7" up and 3" down, which is why you see OME users go to L shocks to space down their travel at 3"+ lifts. This unbalance is undesirable for rock crawling, although you might like it for high speed overland travel where you are hitting big bumps at speed - you would also probably keep smaller tires for this usage and not have the contact issues.

The bottom line is you need to look at where your shocks actually fully compress and ensure your bumpstops are protecting the shocks. If at full compression you have tire/body contact, spacing the shock travel down while ensuring you keep a good compression/droop balance is the goal.

This is easily accomplished on the 80, and using eye adapters without increasing shock travel will help keep the rear tires from angling so much into the wheel wheels. I have no issues picking up rear tires and have avoided the issues that come with adding too much travel. Plus, the front of the 80 can't use any extra travel anyway, so front to rear balance should always be a consideration.

This is why I wheel with my front swaybar removed and rear attached. It is well balanced for such a big pig.

No substitute for measuring on your rig - you can tune from there :hill:


Why not just get longer shocks then? If they are just moving the travel down, and not giving you more travel, then the whole lift is pointless. You could cut the body, run the same sized tires, and keep the COG lower. Now, if you have the longer springs, chances are you can get more travel from them, and thus the lift makes sense. But not if you are only using part of the travel you just gained.

In your case, you have 10" of travel with a 3 " lift. Go to a 12" or 14" shock, and get more travel, leaving the original bumpstops in place. Now you can use the full benefit of those longer springs. And you can keep the 50 50 split you desire.

You make a good point for the front balancing the rear. The main issue with the 80 rear's is likely the same as modern runners. 5 link with a panhard means more arc which means more rubbing the more travel you gain.. Running new link set ups front and rear would be the ultimate fix for the 80, but not particularly feasible for most.

For Myself, dave, and farnham, the front to rear balance is a total joke, as with IFS rigs, we do not come close to having balanced rigs. The rear does all the work, and the front is just along for the ride.

Corbet
07-03-2010, 09:32 AM
Nay, I would say I have the same suspemsion philosophy as you, but simply can't afford the "kit" I want right now. This Iron Man is an affordable solution to a worn out stock suspension which IMO has become a safety issue while daily driving.

Does anyone have the eye to eye measurements for OME shocks? I have not been able to find a source to compair them with the Iron Man's. I'm considering getting the shocks from the Iron Man's 4" kit to help space down the lift. But I'm worried that even with spacers on the springs I might unseat a spring at full droop.

The springs I'm getting are very similar to the OME 850/863 but 5mm longer unloaded.

Front: TOY024C, +242 lbs over stock, 500/505mm unsprung
Rear: TOY013B, +660 lbs over stock, 485/495mm unsprung

If I choose to go with the longer shocks they are 20mm longer at full compression and about 50mm longer at full extension over the shocks that come with the 2" kit. So dropping my bumpstops 2" to prevent 35's from rubbing will definitely take up the extra 20mm length of the longer shock at full compression but I'm not sure if my springs will stay seated even with 30mm spacers on top of them.

Corbet
07-03-2010, 03:37 PM
OK, I found some OME shock specs on Christo's website. Looks like the Iron Man shocks are within 2-3mm of the N73/74 and L's

Has anyone ever gone to L's with an OME "heavy" kit and spring spacers? Or have the the normal shocks always had enough additional droop?

coax
07-03-2010, 05:24 PM
I can measure my unarmored 850/863's with standard OME shocks if it would help, would just need to know where you want me to measure to/from. (Maybe the bumpstop outside of the spring to the axle?) I'm already battling a brake issue so all the wheels are off and easy access :\

My gut feeling is that this setup doesn't leave much droop left. I'd be interested to see where a stock truck sits in terms of both up and down travel to compare to.

Corbet
07-03-2010, 07:07 PM
Corey, I'm just courious how much more droop your shocks could allow? Do your springs unseat before your shocks fully extend?

coax
07-03-2010, 07:36 PM
Corey, I'm just courious how much more droop your shocks could allow?

This is on my list of things to do. I suspect there is about 4 more inches droop avail, maybe less in the rear.


Do your springs unseat before your shocks fully extend?

Nope, but I'm running the standard OME shocks, which have the same dimensions afaik as the OEM shocks. I'm hoping to go L's in the front in the near future as I think more available down travel might be a safer option, though I still need to do some more measurements. Check out this thread, its got some good info. http://forum.ih8mud.com/80-series-tech/93169-so-what-point-do-you-need-go-l-shocks-2.html

Here are some pics...not terribly useful without another OME shock to reference, but here you go.

Corey

http://picasaweb.google.com/hobogoesrogue/Shocks#

Nay
07-06-2010, 02:17 AM
Why not just get longer shocks then? If they are just moving the travel down, and not giving you more travel, then the whole lift is pointless. You could cut the body, run the same sized tires, and keep the COG lower. Now, if you have the longer springs, chances are you can get more travel from them, and thus the lift makes sense. But not if you are only using part of the travel you just gained.

In your case, you have 10" of travel with a 3" lift. Go to a 12" or 14" shock, and get more travel, leaving the original bumpstops in place. Now you can use the full benefit of those longer springs. And you can keep the 50 50 split you desire.

You make a good point for the front balancing the rear. The main issue with the 80 rear's is likely the same as modern runners. 5 link with a panhard means more arc which means more rubbing the more travel you gain.. Running new link set ups front and rear would be the ultimate fix for the 80, but not particularly feasible for most.

For Myself, dave, and farnham, the front to rear balance is a total joke, as with IFS rigs, we do not come close to having balanced rigs. The rear does all the work, and the front is just along for the ride.

Longer shocks = more suspension travel unless some restriction is designed into the system (see 80 series radius arms). This is not always a good thing. On an 80, a longer shock will have zero effect on the front suspension without some other modification - it cannot even use the articulated travel of a 10" shock. I initially was sure I would "re-link" the front of my 80, but I am now a pretty strong advocate of leaving it alone because it adds so much stability in so many situations where you really need to feel the limits without getting far enough to risk a flop or worse.

Lifting an 80 has some particular issues. First, the lift is never pointless from a clearance perspective given the 80's low hanging frame, and to be honest while you can run 37's on a pretty small lift frame and bracketry clearance remains an issue vs. going taller. The larger issue, however, is that 80's springs don't tend to get much longer, if at all, as you lift. This is because the top heavy pig needs a lot of extra spring rate as you go higher. A 12" or 14" travel shock is going to generally exceed the sweet spot of the spring motion on a lifted 80, probably dropping the spring off the tower. This is particularly true when you buy springs made for expedition weight and then try to rock crawl with it. Anybody who has noticed how much relatively easier it is to lift a leaf sprung 60 "big" vs. an 80 is seeing this issue on display.

Now, my coils are progressive with a series of dead winds at the top that will unstack during articulation - this allows a balance of a very firm underlying spring rate with a somewhat longer coil, but I am still using almost all of the effective travel of these springs with just a 10" travel shock. Adding travel would simply place more of the suspension movement outside of the range where the spring itself is functioning as designed. This makes for nice web pics, but may not be optimal in situations where you don't want any sudden suspension geometry surprises.

The bottom line is an 80 has a really solid sweet spot right at 3-4" of lift. You can go to a DC shaft and have perfect caster and pinion alignment, you have enough lift to run 37's if you want to without any major trimming with a good balance of COG and clearance (within "typical" usage), and a 10" travel shock mounted inboard on the axle tube is generating a very nice amount of travel in the rear 5-link at the wheels without causing any excessive issues or forcing higher spring rate coils to operate outside of preferred range of motion.

You can try to design an 80 series suspension outside of these parameters, but that is a tuner's game and mostly you'll end up sounding like me in posts like this (the "inch here, performance there" arguments :D). Most 80's that are pushed well outside of these parameters end up getting sold, whether it is portal axles, 3-link fronts, chopped tops, or whatever. I see plenty of 6" lifts on 35's. I'd rather be at 4" on 37's in the great majority of situations.

So in the end, adding a bunch of travel to an 80 doesn't really make any major positive performance difference IMO. Its size, weight, and (lack of) clearance will always dominate with dual lockers, surprisingly good balance, and ability to run huge tires on a smallish lift largely offsetting those characteristics.

This video starting at 2:48 I think shows it perfectly - as the rear drops there is almost no body movement, no tires pick up, balance stays perfect. The second video also shows the 80's limitations perfectly as those rear control arm mounts will beach you in rock gardens again and again. No amount of flex will care for this, but you have to introduce the considerations of more lift to deal a condition you may see a couple times a year.

Chinamans Flex:

http://www.vimeo.com/7951992

Spring Creek Hanging. Again.

http://www.vimeo.com/12729246


YMMV, but it isn't likely in an 80 :D