sua vs. soa (1 Viewer)

[Adventure Teq]

That fawkin rocks!!!

I knew I should have turned around yesterday and gotten a pic of this late 90s Grand Cherokee that was lifted about 3 feet with some kind of weeny 1" looking tube and about 49" tires. Damn!

That is awesome dude. LMAO

 

[3jvj]

Uuggh. I think I'm going to hurl.

WHY?!?

 

[camcruiser13]

i cant stop laughing, mtdew meets keyboard

 

[biggraypig]

Why? So you can look at cleavage. There is no other reason to do somthing like that.

 

[LT]

:shotts:

 

[4x4Poet]

I'm not impressed by SOAs on Cruiser axles. I think SOAs on swb rigs are unstable unless on wide, full-size axles. Swb SOA rigs aren't ever as stable off-camber as swb SUA rigs, but won't be dangerously so on wide axles. SOA conversions can be tricky from both a mechanic's competence and engineering standpoint.
I think far too many 4-wheelers ruin a swb rig with SOAs. FJ40s need SOA advantages far less than other swb 4x4s, IMO, because FJ40s have fairly long springs with a decent width compared to CJs and other swb rigs. FJ40 spring design lends itself well to SUA lifts. The many leaves of FJ40 oem and SUA lift springs also resist axle wrap– the cause of much carnage on 4x4s.

SUA 4"-5" lift springs with many progressive leaves, tapered & diamond cut tips, and poly pads ride better than oem springs, IMO. Better than old, worn out oem springs,anyway. HFS springs and quality custom springs like from Alcan Spring have good ride quality and resistence to axle wrap. Alcan informed me that they can make front springs with less or more arch in half of each spring assy to compensate for any castor altering effect of longer than stock shackles to negate the need for shims between the springs and axle perches.

In the long run, it's all in what compromises you want to make. A rockcrawler SUA lift FJ40 sacrifices some boulder crawling capability while a rockcrawler SOA lift rig sacrifices some off-camber safety and also more dependablility against carnage due to the increased stresses on steering, frame, and knuckles. And, as mentioned, SOAs sacrifice more of the contents of one's wallet.

IMO, today's wheelers think they need all kinds of extreme mods to tackle everyday obstacles. Needing extreme mods to boulder crawl is one thing, but I've heard wheelers say one can't get thru the Rubicon without lockers and at least 33" tires which is incredibly ridiculous when one considers that tens of thousands of FJ40s, CJs, EBs, et al were making trips thru the Rubicon since the 50s (60s for FJs/EBs) shod with skinny 31" tires, with no lockers, and on stock suspensions. Shoot, grandmas drove thru the Rubicon in stock heeps before most of us had drivers liscenses. I'm all for cool, functional mods, but some dear folks need to learn to drive off road with open diffs before they think of making mods.

...I am looking at the faq's to see what I need for power steering and disc brakes.
Both projects seem to be way over my abilities though.
I will have to find someone with the mechanical ability to help with guidance so I don,t screw things up. I take steering and braking a little to seriously...

Wise attitude. I can do my own brakes and most general welding but leave welding steering brackets/componets to trusted pros. Does anyone have any suggestions for a good Cruiser shop ner Mozzio?

Btw, I disagree with the idea that power steering should be done before suspension. I think both should be considered together since PS design is driven somewhat by suspension design such as pitman arm length, SR incorporation (I'm against), any body lift used (drives steering intermediate shaft length), etc. Even installing poly body bushings makes a small difference over worn rubber. Planning is good.

 

[4x4Poet]

Why? So you can look at cleavage. There is no other reason to do somthing like that.

The cleavage of 18-wheeler truckers?!!

 

[camcruiser13]

were did you cut and paste that article from. i have no worries going on off camber hills and the pors outway the cons by a landslide.

soa and be done

 

[camcruiser13]

that jeep rocks

 

[Trollhole]

I'm not impressed by SOAs on Cruiser axles. I think SOAs on swb rigs are unstable unless on wide, full-size axles. Swb SOA rigs aren't ever as stable off-camber as swb SUA rigs, but won't be dangerously so on wide axles. SOA conversions can be tricky from both a mechanic's competence and engineering standpoint.
I think far too many 4-wheelers ruin a swb rig with SOAs. FJ40s need SOA advantages far less than other swb 4x4s, IMO, because FJ40s have fairly long springs with a decent width compared to CJs and other swb rigs. FJ40 spring design lends itself well to SUA lifts. The many leaves of FJ40 oem and SUA lift springs also resist axle wrap– the cause of much carnage on 4x4s.

SUA 4"-5" lift springs with many progressive leaves, tapered & diamond cut tips, and poly pads ride better than oem springs, IMO. Better than old, worn out oem springs,anyway. HFS springs and quality custom springs like from Alcan Spring have good ride quality and resistence to axle wrap. Alcan informed me that they can make front springs with less or more arch in half of each spring assy to compensate for any castor altering effect of longer than stock shackles to negate the need for shims between the springs and axle perches.

In the long run, it's all in what compromises you want to make. A rockcrawler SUA lift FJ40 sacrifices some boulder crawling capability while a rockcrawler SOA lift rig sacrifices some off-camber safety and also more dependablility against carnage due to the increased stresses on steering, frame, and knuckles. And, as mentioned, SOAs sacrifice more of the contents of one's wallet.

IMO, today's wheelers think they need all kinds of extreme mods to tackle everyday obstacles. Needing extreme mods to boulder crawl is one thing, but I've heard wheelers say one can't get thru the Rubicon without lockers and at least 33" tires which is incredibly ridiculous when one considers that tens of thousands of FJ40s, CJs, EBs, et al were making trips thru the Rubicon since the 50s (60s for FJs/EBs) shod with skinny 31" tires, with no lockers, and on stock suspensions. Shoot, grandmas drove thru the Rubicon in stock heeps before most of us had drivers liscenses. I'm all for cool, functional mods, but some dear folks need to learn to drive off road with open diffs before they think of making mods.
Wise attitude. I can do my own brakes and most general welding but leave welding steering brackets/componets to trusted pros. Does anyone have any suggestions for a good Cruiser shop ner Mozzio?

Btw, I disagree with the idea that power steering should be done before suspension. I think both should be considered together since PS design is driven somewhat by suspension design such as pitman arm length, SR incorporation (I'm against), any body lift used (drives steering intermediate shaft length), etc. Even installing poly body bushings makes a small difference over worn rubber. Planning is good.

Look at where he lives. There are not many rock or hills in the pan handle of Florida. SOA would be a good option where it is flat and the need to have more clearance for taller tires. Off camber for very difficult trails might be more tricky in a SOA. BUt that depends on tire size and backspacing. If you compare a 2 inch backspacing rim with 12.5x35 inch tire with a person running stock rims and 10.5inch tires. There is a pretty big difference. I like keeping all 4 wheels on the ground with a SOA than having one wheel up in the air.

In my opinion a person with a hard top and doors and SUA is a lot more likely to tip over than someone SOA and a soft top.

It would be interesting in seeing what the maximum angle would be for both a SOA vs SUA vehicle with the exact same height and accessories. I'd be willing to be they would be very close. Especially in an off camber situation. Because a SOA will keep the tires on the ground a lot more than a SUA which means the tire off the gound just raised the vehicle center of gravity.

 

[4x4Poet]

were did you cut and paste that article from. i have no worries going on off camber hills and the pors outway the cons by a landslide.

soa and be done

The thoughts are mine. The "SOA is superior to SUA" mantra has become conventional wisdom due, IMO, to the 4x4 mags that promote SOA for something new, photogenic, and a benefit to advertisers. I don't accept conventional wisdom for its own sake. But I wasn't trying to start a debate or argument. I just wanted to offer my opinion along with the others. I'm not against well done SOAs. I'm just not an advocate.

In my defense, 4x4 mags over the last decade presented photos of full-bodied, swb SOA rigs that experienced rollovers by at least a 10 to 1 margin in comparison to swb SUA rigs. Don't believe me? Do a survey among your old 4x4 mag copies. With some exceptions, full-bodied swb SOA rigs have been resoundly proven unstable in hardcore, off-camber wheeling situations though the swb SOA rigs probably could tackle tougher terrain (not risky off-camber) before reaching a potential rollover situation. SOA is arguably better for most extreme obstacles but not necessarily better for hardcore wheeling in general.

No one will admit this in the mags or on BBs, though, because it ruins their "extreme is better" mindset and the ad profits made. Not that I'm against better and better products like the outstanding chromo Longfields or Crane/Dedenbear knuckles (come on, Marlin K.!), etc. I'm glad to support such companies as my budget allows.

I think the mindset is akin to "more cam is better" espoused by those seeking more horsepower instead of first emphasizing torque in the power range needed. I also think the SOA mindset ruins a lot of new wheelers to the sport because they rarely learn capable alternatives in a wheeling world controlled mostly by the SOA crowd. Nevertheless, that's a minor concern in the overall scheme of things. And buggies are a different animal not applicable to the full-bodied Cruiser discussed here. To each his own.

In your defense, most of the rolled SOA rigs were Heeps.

 

[camcruiser13]

thats kool, well thought out, i have backspacing and wide tires so i dont know the dif. i just love my rig 30x more now that it is soa, more capable than before and looks 5x more badass, and the chicks dig it





i must agree with troll, well spoken,

i value everyones opinion, well except for hawks, hes a fruit cake

 

[4x4Poet]

Look at where he lives. There are not many rock or hills in the pan handle of Florida. SOA would be a good option where it is flat and the need to have more clearance for taller tires.

Good point. Goes back to other posters that mentioned it depends on what the owner wants. If he stays in Florida mud, maybe SOA is needed to make room for huge mud tires. If he favors Tellico trips, maybe SUA has its place in his deliberations.

...Off camber for very difficult trails might be more tricky in a SOA. BUt that depends on tire size and backspacing. If you compare a 2 inch backspacing rim with 12.5x35 inch tire with a person running stock rims and 10.5inch tires. There is a pretty big difference.

Since that's true for both SUA and SOA rigs, I fail to see you point.

I like keeping all 4 wheels on the ground with a SOA than having one wheel up in the air.

It's all in how it's done. SUA lifts don't leave one wheel in the air if they are done with many leaf springs with poly sliders and other such improvements. Unfortunately, most SUA/SOA comparisons are done with 5-leaf, off-the-shelf crappy SUA lift springs instead of quality custom springs or well done pre-made springs like CCOT's HFS line that are basically packaged custom springs.

In my opinion a person with a hard top and doors and SUA is a lot more likely to tip over than someone SOA and a soft top.

Again, since that's true for both SUA and SOA rigs, I fail to see you point.

It would be interesting in seeing what the maximum angle would be for both a SOA vs SUA vehicle with the exact same height and accessories. I'd be willing to be they would be very close. Especially in an off camber situation. Because a SOA will keep the tires on the ground a lot more than a SUA which means the tire off the gound just raised the vehicle center of gravity.

Not if quality springs were used for the SUA. Hard data is difficult to come by, though, so opinion is surely in play.

 

[4x4Poet]

...and the chicks dig it.

I got nuthin'

 

[HogDriver]

[It would be interesting in seeing what the maximum angle would be for both a SOA vs SUA vehicle with the exact same height and accessories. I'd be willing to be they would be very close. Especially in an off camber situation. Because a SOA will keep the tires on the ground a lot more than a SUA which means the tire off the gound just raised the vehicle center of gravity.[/quote]

I bet you it would be alot different then what you think. CG (center of gravity) is huge when it comes to off camber stuff. An inch here or there in ride height compared to none will change your CG. Add in different motors (more or less #) and that too changes your fore aft CG, then combine that with height = potential off camber issues. IMO

My point is.... with that lifted Heep why have rocksliders... ??

Cheers

 

[Mozzio]

As always I am impressed with the amount of information that is offered in this forum.
I really don't see Tellico in my near future.
like the mud but miss runnin in the snow.
After reading all the posts I'll stay spring under for a while. At least until I have to upgrade to later model axles.

 

[4x4Poet]

[It would be interesting in seeing what the maximum angle would be for both a SOA vs SUA vehicle with the exact same height and accessories. I'd be willing to be they would be very close. Especially in an off camber situation. Because a SOA will keep the tires on the ground a lot more than a SUA which means the tire off the gound just raised the vehicle center of gravity.

I bet you it would be alot different then what you think. CG (center of gravity) is huge when it comes to off camber stuff. An inch here or there in ride height compared to none will change your CG. Add in different motors (more or less #) and that too changes your fore aft CG, then combine that with height = potential off camber issues. IMO

I forgot to mention that, in off-camber situations, uphill SUA lift springs are already in a positive arch and thereby reisist any more arch which makes the whole rig more stable. Along with positive arched downhill SUA lift springs that better resist compression than ~flat SOA springs.

Uphill SOA lift springs in off-camber situations transition from negative/flat/nearly flat to arched with little resistence by the uphill springs. Downhill SOA springs also usually have little arch with few leaves and thereby easily go into negative arch with far less force than SUA lift springs. This is a double whammy effect. Ever notice that a swb SOA rig often rolls with little warning? I think it is this negative arch to positive arch quick unweighting that is both an articulation advantage and also the primary cause of SOA inherent instability in off-camber situations. Wider axles/less rim backspacing/hub spacers, etc. all help combat this. JMO.

My point is.... with that lifted Heep why have rocksliders... ??

Lol! That's hilarious! I totally missed the sliders. I had to go back and look.

 

[camcruiser13]

i just went back and looked myself, pretty funny stuff. hahaahhhahaaa

 

[Gotta40]

I forgot to mention that, in off-camber situations, uphill SUA lift springs are already in a positive arch and thereby reisist any more arch which makes the whole rig more stable. Along with positive arched downhill SUA lift springs that better resist compression than ~flat SOA springs.

Uphill SOA lift springs in off-camber situations transition from negative/flat/nearly flat to arched with little resistence by the uphill springs. Downhill SOA springs also usually have little arch with few leaves and thereby easily go into negative arch with far less force than SUA lift springs. This is a double whammy effect. Ever notice that a swb SOA rig often rolls with little warning? I think it is this negative arch to positive arch quick unweighting that is both an articulation advantage and also the primary cause of SOA inherent instability in off-camber situations. Wider axles/less rim backspacing/hub spacers, etc. all help combat this. JMO.
Lol! That's hilarious! I totally missed the sliders. I had to go back and look.

What i'm reading here is that you're comparing worn, loose springs, to new, tight springs. obviously the worn in springs are going to flex more on a sidehill. to be fair in compairing a soa and sua, you'd probably have to have new stock height springs on the soa to compare to a lifted sua situation. Sound right? obviously that defeats the cheap lift purpose. Just my thought.

 

[4x4Poet]

Gotta40, I think you have a point. It is difficult to speak in generalities regarding multiple engineering/physics factors. So such factors as new vs. old springs would alter arguments to some degree. I tried to present arguments with all things being equal.