Makes sense. How hard is a cut and turn on an 80? Would it really be worth it just to avoid a DC shaft? Also, the flipped arms leave the tie rod even more exposed. You think that will be an issue? ... although i doubt it.
Radius Arm Flip
- Thread starter adventr
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
Makes sense. How hard is a cut and turn on an 80? Would it really be worth it just to avoid a DC shaft? Also, the flipped arms leave the tie rod even more exposed. You think that will be an issue? ... although i doubt it.
I believe at some point you have to - even a DC won't work. I don't know at what point that is, I'm no drive shaft expert or even really a novice. I mean as far as the pinion and caster angle go, they don't care if they're under an 80 series or a SOA application - and SOA is usually where you see people start getting into cut and turn, it's also where 6+" of lift come into play.
Anyway - as far as I have been able to find, cut and turn on an 80 is no different than any other landcruiser axle. Cruiser Outfitters Doesnt' appear to charge any extra for them, and really, $150 if you do the clean up yourself isn't a bad price at all.
Humm.. the rear lower control arm mounts are part of a 5 link system, not the same deal as a radius arm.
Panhard and drag link are also not like a radius arm. They have two pivot points, radius arm only has one, and everything rotates around that one point regardless of shape of arms or if they are mounted top bottom or middle.
Where did I say that rear LCA's, panhard, or drag link were the same as a radius arm?
Shape, number of pivot points, or the number of links that they're a part of has nothing to do with the fact that they all perform better when closer to parallel to the frame/axle.
This is the whole idea behind the drop brackets.
From MAF's site on the control arm brackets:
Where did I say that rear LCA's, panhard, or drag link were the same as a radius arm?
I just quoted your comparison - so I'm not sure where you're confused.
Yes, 4 links 'like' to be flat. Yes, radius arms 'like' to be flat.
Changing the mounting of a 4 link to the top of the axle makes the links more flat.
Changing the mounting of a radius arm to the top of the axle does not make it more flat.
Where's the confusion?
Last edited:
here's some info on cut and turn
Spring Over Axle - December 1999
Cutting and Turning
not a requirement for the radius arm flip - sorta the reverse, if you want to cut and turn, you have to do something with the arms - like flip them.
Spring Over Axle - December 1999
Cutting and Turning
not a requirement for the radius arm flip - sorta the reverse, if you want to cut and turn, you have to do something with the arms - like flip them.
You're assuming in your image that one of the mounting points stays the same.
That is not true. You are moving both axle mounts, so your image is incorrect.
And, regardless, measure the angle your arms are at in your picture. Are they both at the same angle?
From the look of your picture by putting the arms on top of the axle it definitely decreases the angle of the arm
Why would it not make them more parallel to the frame than being under the axle?
At six inches of lift the front arm angle is pretty drastic and I dont think it was designed to run a that type of angle
I have noticed that when going to climb something that the front seems to want to walk under the vehicle and the front of the truck wants to raise up by the seat of the pants gauge
And I think that is do to the arms being at such a steep angle
Why would it not make them more parallel to the frame than being under the axle?
At six inches of lift the front arm angle is pretty drastic and I dont think it was designed to run a that type of angle
I have noticed that when going to climb something that the front seems to want to walk under the vehicle and the front of the truck wants to raise up by the seat of the pants gauge
And I think that is do to the arms being at such a steep angle
- Thread starter
- #70
None. I did away with the front swaybar a long time ago. IMO, with a heavy front spring rate (220+), the front swaybar isn't needed on an 80 series.
There's less body roll now (very close to none), than there was when it was bone stock and still had the swaybar.
Clarification- Did the less body roll come from springs or the flip?
yep they're different - but the axle acts exactly the same way - follows exactly the same path, that's not true when you move the mounts on a 4link.
- Thread starter
- #73
The less body roll came from the springs. The springs I'm currently running (TJM 7") are 300lb linear springs. Same rate as OME Comps.
Also, I didn't run a front swaybar back when I was on J springs either (220lb linear I think), and never had a problem with body roll.
Flipping the arms did seem to soften up the ride in the front of the cruiser. I think that mostly comes from the fact that the springs are now straight up and down, versus being bowed like they were with the arms underneath.
Yes it does move in the same path but I would think that having the arm at less of an angle would affect how it handles
with the radius arm setup you have to picture an imaginary arm that goes straight from the middle of the axle to the pivot point at the frame. The axle will follow that path regardless of where the curved arm actually attaches to the axle. With the arms on top you gain clearance under the axle and may push the axle forward a little, but the effective angle is the same.
I like the flipped arms and the cut and turn seems like the way to go. Also, If you built new brackets I wonder if you could make them a little wider on each side and add spacer to free up some of the binding issues with the radius arms.
It does travel on the same path but at static rest the angle is not the same on top as it is below the axle
Look at a truck with stock suspension the arm has quite a bit of a less angle to the arm as opposed to a truck with 6 inches of lift
It also handles quite a bit different even with castor correction off road
Like I said above I have noticed that when going to climb something off road say a ledge or a really big rock it feels like the axle wants to walk under the truck and I attribute this to the angle of the arms being so steep
That is just how it feels
But am far from an expert that is for sure
that is because the center of the axle is higher on the arc with the shorter springs -
Once again to quote MAF:
The fact is that the angle of the arms does have an effect on how it handles various forces. It's not the height of the frame bracket mount to the frame that matters, it's the angle of the arms.
So as I've pointed out before, a control arm flip does the same thing that the MAF drop bracket does, just on the opposite end of the link.
And again, your picture assumes that one link stays in the same position, and the other is mirrored on the other side of the axle. Neither of these assumptions are necessarily true.
Look, this is basic geometry here. Here's some basic facts.
1) The length of the arm controls the radius of the circle that the end point (axle mounts) will travel around the pivot point (frame mount). Since we're not changing the length of the arm, that circle stays the same meaning that the end point (and axle, since it's attached) will always follow the same path. This has never been in dispute.
2) The angle of the arms determines at what point in that path the end point (axle mounts) exist. If you lessen the angle, the end point has to move up to 90* or 270* (assuming the end point starts below the pivot point). If you increase the angle, the end point moves down towards 180*.
#2 is what controls where the axle mounts (and axle, depending on how that's connected) "live" in relation to the frame mount. So we're not talking about changing the path that it travels, in order to do that you'd have to lengthen or shorten the arm. We're talking about changing the position in the path that the arms travel in, and what effect that has on acceleration, braking, and handling.
Look at the image below (attached to the post).
In #1 (stock), if the axle moves down 1" it will be pull rearwards further than in #2 or #3. If it moves up 1", it will move further forward than in 2 or 3 as well.
If the axle is moving forward and back, it's worse for handling, braking, etc than if it's moving perfectly straight up and down. This is why the drop arm or control arm flip both improve handling/braking/etc.
Gotta agree with Walking Eagle and others on this, the position of the arms does not affect the geometry, because the line you're concerned with is the one drawn between the axle shaft and the rear mount, the path force takes. The actual physical arm could be shaped like a giant 'C' and curve over the hood, doesn't change the force's path. When the tire hits an obstacle, the force travels through the tire and wheel to the axle, and from there to the frame mount of the radius arm. If that line of force is horizontal, any force below the midpoint of the tire will push the axle up. As the line angles down, the same force at the midpoint of the tire will force the axle down, or the truck up, effectively pushing the axle under the truck. That makes things feel harsher, because instead of the axle moving up easily, more of the force is transferred to the frame. The steeper angle you put that line of force at, the harder it is to get the axle to move upwards when it hits a bump. It's not an easy concept to wrap your mind around, but once you do you'll see that the arm itself doesn't matter. Lowering the frame bracket or lengthening the arm are the only ways to improve that geometry. Flipping the arms does give oodles of clearance for steering bits though, which is why I keep contemplating it.
This is what I am trying to say kind of
If you put the control arm on top of the axle you are altering the angle of the arm
The arm on top of the axle has less of an angle to the axle than being on the bottom
Yes your line still goes from the center or axle to center of frame mount
I get that
But with the arm on top the angle of the arm has been changed and the line from the axle to frame is still the same
The path of the travel is unchanged but the angle of the arm has
And like you said as the arm angles down more the more it feels like the axle want to walk under the truck and also push the front end up
This is the feeling I get from the front