Flexing the 3 link (4 Viewers)

[4WheelUnderground]

I'll just leave this here

Beta test results in a week or two for the front. Alfa testing rear suspension starting this December.

 

[Booger weldz]

You are opening a new can of worms that is defined by the 11 degrees of oversteer presented on toyrovers 2nd spreadsheet.

Edit:delancys first pic

Actionjackson gets pioneer credit and respect, but theres so much more evolution. He owns linked 80 front birth, but thats still 2005(?).

We can take his ambition and nickkle and dime it into perfection.

 

[Douglas S]

The 80 rear steers significantly, but it's really not that significant of an issue. Based on a quick look, the cost to remedy it would far outweigh the benefits IMO (the gas tank would need to be somewhere else).

 

[Delancy]

I'll just leave this here
Beta test results in a week or two for the front. Alfa testing rear suspension starting this December.

I know you ain't Burger King, but was second or third respondent in the two year old thread that started all of this on Mud.

Personally, I'm in for a holistic approach to the entire suspension.

Tired of cobbling chit up.

You are opening a new can of worms that is defined by the 11 degrees of oversteer presented on toyrovers 2nd spreadsheet.

Not a new can, but the other end of the same can.

What good will it do to fix half the issues?

 

[Delancy]

The 80 rear steers significantly, but it's really not that significant of an issue. Based on a quick look, the cost to remedy it would far outweigh the benefits IMO (the gas tank would need to be somewhere else).

Three link rear. Been doing it for years on the lesser Toyota's, with the gas tank issue.

 

[Delancy]

@Booger weldz

That's why I was quick to say that picking it apart wasn't the intent.

Regardless, the condition would exist with any three linked front.

 

[Booger weldz]

That 'condition' exists bacause of a rollaxis angle.

@Booger weldz

That's why I was quick to say that picking it apart wasn't the intent.

Regardless, the condition would exist with any three linked front.

@Booger weldz

That's why I was quick to say that picking it apart wasn't the intent.

Regardless, the condition would exist with any three linked front.

 

[ToyRoverlander]

Which can be fixed in multiple ways methinks. Lengthen and triangulate the lower links as much as possible. Just by pushing the lowers out on the axle by 3" each side (shock mounts need to be relocated) the RAA gets reduced by 3degrees. Moving the frame mounts 2" inboard shaves another 1,3 degrees of it. Going from 11,33 to 7,36 degrees. Now move the lowers axle mount to centreline instead of way below it and you end up with a 2,69 degrees RAA. Antisquat also dropped, a bit too much perhaps, down from 113% to 40,31%.

Totally redoing the rear is another option, going to a double triangulated 4link and ditching the panhard. A bit too much work probably.

Rear roll steer sucks! But by far not as much as roll steer on the front axle which can drastically reduce steering angle..

 

[ToyRoverlander]

Was looking at the screenshot of the front setup. Is there really 15,5" of seperation between the radius arm bushings at the axle end? Can't imagine it being that much. If it's less, and the lower link axle end mount needs to be a bit further forward the RAA will be less than the shown 17degrees.

 

[yOHda]

Feels like a pirate thread

ToyRoverlander: I can take some measurements of the radius arms today when I go to the shop if your question isn't answered. That kind of looked a little funny to me as well, but I didn't have one in front of me to measure.

Brian, don't you have a upper link bracket already made for the 80 rear axle?

Booger, given the amount of oversteer the rear axle has, how much understeer would you put into the front to counteract, if any? My current 3 link has 75% anti-dive and .18* of understeer. The way I understand it my rear leaves also induce understeer. I should move my links a couple of holes just to see how the truck reacts.

It looks like there are no real benefits to keeping the rear suspension. Cut it out, Do it right.

 

[ToyRoverlander]

That would be fantastic if you could do that, thanks!

 

[Delancy]

Which can be fixed in multiple ways methinks.....

Totally redoing the rear is another option, going to a double triangulated 4link and ditching the panhard. A bit too much work probably.

Three link is the only way without moving the gas tank.

Sol's FJC is at Don's for a front redo and three link rear. It'll be very interesting to see what they come up with, since the rear poses the same issues.

Guy's a friggin' magician.

 

[Delancy]

Cut it out, Do it right.

Amen.

 

[Booger weldz]

Its 7.5" between them(3.75"). Good catch. Keep looking, you might find a couple more measurements that are suppose to reference off centerline distance, not whole seperation.

Was looking at the screenshot of the front setup. Is there really 15,5" of seperation between the radius arm bushings at the axle end? Can't imagine it being that much. If it's less, and the lower link axle end mount needs to be a bit further forward the RAA will be less than the shown 17degrees.

 

[ToyRoverlander]

Ok, fixed it and edited the screenshots I posted earlier to show the corrected one as not to create any confusion. Dropped the RAA to 13 degrees from 17degrees.

 

[Booger weldz]

Been doing a few paralell 4 link w panhard and wishbone upper 3 links for guys at work with lowered 2wd GM vehicles.

With 24" links and 9" of airbag, geometry can be drastically altered. At ride height the roll centers dead flat, if not slightly neg, but with the bags inflatted it shoots to the moon, as well as AS. If you do a smoky burnout with the bags inflated the chassis doesny barely budge(even though AS is probably over 200%. however, if you drive the truck w the bags fully aired up it wanders all over the road and is borderline dangerous at speed(because of the massive oversteer).

 

[yOHda]

What is the separation of the links at the axle and frame on those 2wd trucks?

I'd imagine those link angles are pretty steep with the bags fully inflated.

 

[Booger weldz]

Itll drive half better much like the difference in a 2.5" OME lift vs a 6" slee.

The issue with the rear is you cant really triangulate the lowers cause the gas tank. You cant get crazy on flattening them as youll kiss the frame on uptravel. You cant outboard them cause theres a shock....

I have to put a slight bend in my front lowers to clear the frame on uptravel. They are mounted above axle centerline and triangulated 10-12 degrees. Its essentially the 4wu minitruck brackets at the axle end

[QUOTE="Delancy, post: 9213905, member:



Not a new can, but the other end of the same can.

What good will it do to fix half the issues?[/QUOTE]

 

[Booger weldz]

What is the separation of the links at the axle and frame on those 2wd trucks?

I'd imagine those link angles are pretty steep with the bags fully inflated.

7" at both ends. It also tears the tacks off a mockup jig when articulated at about 8"(inherent binding of a 5 link system). I tacked the frame side mounts down to a fab table, then tacked the axle end to a 5' 3.5" tube. Lifted one side of the tube with the overhead to about 8" and *snap*!

 

[yOHda]

I can understand that. As dumb as it sounds, I used to try(and still do) different suspension configurations on rc trucks. An Axial SCX10 is a great visual aid for learning about suspension.