Topic: SUA vs SOA

[Bounty Hunter]

Oh, I run no swaybar or trackbars, highway use is just fine.

[Jeffy]

This is what I was looking for.  What happens when you crank the steering to the right and stuff either front wheel?  Have you got the perches jacked up enough or the knuckles tiped back so that the draglink doesn't hit the spring?

It clears fine or else I wouldn't not have done it.  The guy who helped me set mine up runs his the exact same way.

[oldjeep]

It clears fine or else I wouldn't not have done it.  The guy who helped me set mine up runs his the exact same way.

Couple questions for you, I'm trying to add some tech to this thread.
1) Did you do anything special to make it work, or is that pretty much stock YJ springs with normal height perches?
2) What kind of terrain do you wheel in?  The picture does point out another reason why SOA should have high steer.  Now instead of having springs to ramp the rocks, the tie rod and drag link is the first point of contact.  For forest trails, it wouldn't matter much - in the rocks it wouldn't last long.

I'm not trying to be an a-hole, but I've seen that setup not work in person many times.

[Bounty Hunter]

The springs don't contact as much as the middle of the axle does, since they're tucked up behind the wheels.  Thus the draglink (at the middle of the axle) would be at the same level and risk of contact regardless of SOA or SUA.

You can see a little of my steering here:

[Jeffy]

Couple questions for you, I'm trying to add some tech to this thread.
1) Did you do anything special to make it work, or is that pretty much stock YJ springs with normal height perches?
2) What kind of terrain do you wheel in?  The picture does point out another reason why SOA should have high steer.  Now instead of having springs to ramp the rocks, the tie rod and drag link is the first point of contact.  For forest trails, it wouldn't matter much - in the rocks it wouldn't last long.

I'm not trying to be an a-hole, but I've seen that setup not work in person many times.

Nothing extra ordinary BUT you have to choose the right spring perches.  I'm using Rubicon Express which are a bit taller then regular ones.  This makes a BIG difference in whether it hits or not.  The RE perches are made for SOA specifically.  Not to mention they're offset.  The picture is a bit deceiving since it's show from low down so it looks closer then it actually is.

Terrain: Rocks, rocks and more rocks.  I'm about 3-4 hours from the Rubicon.  I don't use my drag-links as feelers.  It takes a bit more thinking but then you put the tire on the rock and not straddle it.  It's really no safer then SUA though since you can get punched in the center if you try to straddle a rock.  I could raise the tie-rods, if I wanted to put some bends in drag link but I haven't had any problems with it.

High steering would be nice but it's a waste for a D30 when you don't plan on keeping it forever.

[jwalls4x4]

You can see a little of my steering here:

Slightly off subject, but what size are those Swampers Bounty Hunter?  I like your front flares .

[oldjeep]

High steering would be nice but it's a waste for a D30 when you don't plan on keeping it forever.

Definitely - considering what high steer for a D30 costs.  You could do a d44 swap with high steer for that money

[Bounty Hunter]

Slightly off subject, but what size are those Swampers Bounty Hunter?  I like your front flares .

Q78, which is 35.5"x10.5" with 27/32" tread which is only second in depth to the bogger.  The Q78 is close to the 36"x12.5", just a little skinnier with deeper tread.  I like pizza cutters.

[neale_rs]

Definitely - considering what high steer for a D30 costs.  You could do a d44 swap with high steer for that money

This brings to mind the following setup with D30 front axle:

SOA in rear
SUA in front with a tie rod flip to get the steering up higher (I don't think this can be done with SOA in front)

Do you think it would have a significant advantage over straight SUA?
Any significant advantage over Jeffy's SOA/SUA setup?

[oldjeep]

This brings to mind the following setup with D30 front axle:

SOA in rear
SUA in front with a tie rod flip to get the steering up higher (I don't think this can be done with SOA in front)

Do you think it would have a significant advantage over straight SUA?
Any significant advantage over Jeffy's SOA/SUA setup?

I don't think there would be any advantage to doing an SOA only in the rear, unless you were just doing it as a half step on the way to a full SOA.  The clearance gain wouldn't help much since the front is still down lower, and you would have to put in a traction bar to keep the wrap under control.

[Jeffy]

This brings to mind the following setup with D30 front axle:

SOA in rear
SUA in front with a tie rod flip to get the steering up higher (I don't think this can be done with SOA in front)

Do you think it would have a significant advantage over straight SUA?
Any significant advantage over Jeffy's SOA/SUA setup?

That would be the worst way to go.  With the SOA in the rear only, you'd have to deal with axle wrap which isn't so easy to solve.  SUA in the front would be no doubt be stiffer up front so your ride would suffer as well as your flex.   Most crawlers have more flex up front then in the rear anyway.  Off the shelf traction bars don't work well.  Of the guy's I know who tried that route, ended up going custom since those bars kept breaking.  The one setup that really works though is the 'BamBar'.  It's a multi-linked shackle sort of thing.  It was created by a friend of mine.  You can see it here http://www.jeepaholics.com/tech/bambar/

You really need to plan out a SOA and research it well.  Talk to people who've done it.

[neale_rs]

Thanks.  The bambar looks good.  From the geometry it looks like it would induce a bit of squat instead of anti-squat and the main problem would be having enough space under the tub, might require a body lift. 

[jfrabat]

My SOA YJ drives just fine down the interstate at 80mph.

I am not sure I would even drive a stock Jeep at 80mph...  I try to keep it under 75, but that's just me.

You would need to do the same mods between the SOA and SUA if using the same amount of lift, minus having to weld on spring perches.

If you plan to install a CV shaft, you will end up having to weld anyway.  Otherwise, you wont be able to drive at more than 20mph cause the jeep will shake more than a San Francisco earthquake!  Trust me on this one, and dont ask me how I know!!!

My main worry in the case of SOA is sprig warping...  Bounty, how's this issue been for you?

This brings to mind the following setup with D30 front axle:

SOA in rear
SUA in front with a tie rod flip to get the steering up higher (I don't think this can be done with SOA in front)

Do you think it would have a significant advantage over straight SUA?
Any significant advantage over Jeffy's SOA/SUA setup?

I was in the same dilema, and although I know the SOA will outperform the SUA, I decided to go with the SUA for convenience.  But knowing what I now now, I would probably have gone SOA in the front and SUA in the rear...  And if possible, i would swap to D44s...  This will allow you to have more options in the future, like better gearing for bigger tires, and more strength at the axles.

Felipe

[Bounty Hunter]

My main worry in the case of SOA is sprig warping...  Bounty, how's this issue been for you?

Are you talking about spring sag?  My stock springs +1 AAL haven't sagged any, but I extended the bumpstops to limit uptravel, thus making the springs last longer.  Repeated over compression will wear them out quickly.

[oakey]

Well I run a SOA setup....  I believe it is far better than my old 4.5" RE SUA Kit....   But it did cost more to get it right.... We streched the wheel base about 3" also....

Superlift 1.5" Springs - RE Spring Mounts - MORE Bomrangs - TeraFlex HSK - Sams Offroad HD Traction Bar

Ive got a few pics:








l8r,