Equal Length I-beams vs. Un-equal Length (equal geometry?) I-beams. . .

[atomicjoe23]

I'm sure there are advantages and disadvantages to each of these designs. . .I just don't know what they are.

Would anyone be willing to post up the pro's and con's between these two I-beam set-ups?

I'm new to I-beams and I'm trying to learn what I can.

Thanks!

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[ErikShallbetter]

Equal length Beams should have the same (or much more similar) geometry on each side of the vehicle due to the arcs they are swinging being the same length. The con is you are looking at all new mounts, and beams, and steering = more expensive.

[atomicjoe23]

That's what I thought. . .I just wanted to make sure I was on the right track.

[95f150]

That's what I thought. . .I just wanted to make sure I was on the right track.

if im correct, equal length is alot more desirable for racing but if your going out every other weekend and use the truck as a DD then unequal would be fine

[atomicjoe23]

Mine will be for the dirt only. . .I have started to design some equal lengths so I will stick with that.

[Giant Geoff]

The Eq. beams get less bump steer with stock steering over the extended beams buy the extended beams pull more travel over the Eq. beams with the same length shocks.

[Jerry Zaiden]

There are a few ways to look at this.

1) With un-equal length beams you will have equal length radius arms.
2) with equal length beams you will have un-equal length radius arms.

There is a give and take with each. We have found it really does not matter with equal length beams with the average setup. Unless you are going to spend the money to do it right with full hydraulic ram steering, correct steering geometry with all new spindles with correct ackerman etc... then go with un-equal length beams and when you get to it then ad a single swing steering to reduce the bumpsteer.

What is nice about a PROPERLY setup equal length system is you are in control of the complete setup. So yes you can reduce most of the bumpsteer to under 1/8" over 20+ inches of travel.

In most cases I see equal length beams are more of a buzz word then a need. I would also say that in most cases the people who have equal length beams should have stuck with un-equal length beams and spent their money on better parts through out there whole truck because they are on a limited budget.

Now Cameron and Heidi steel were on a mission to prove this point this year and they did with their Baja 1000 win and SCORE championship. They did this with a solid built truck and quality parts through out there build. They kept it simple and to the point of what is needed to WIN.

[Jerry Zaiden]

The Eq. beams get less bump steer with stock steering over the extended beams buy the extended beams pull more travel over the Eq. beams with the same length shocks.

Please explain this.... This should get interesting!

[Giant Geoff]

I just came across this fact from doing it for so long. A 14” shock an my equal length pulls 18” of travel and a 14” in the same mounting spot pull 20” on the driver side and 22” on the passenger side. Sense the arm is shorter the wheel travels more.

[atomicjoe23]

There are a few ways to look at this.

1) With un-equal length beams you will have equal length radius arms.
2) with equal length beams you will have un-equal length radius arms..

I was unaware of the un-equal length radius arms. . .what would this mean if I were setting up equal length I-beams with equal length radius arms?

Why do you need unequal length radius arms for equal length beams?

I've attached a SW's screen shot of what I'm working on. . .single seat buggy with 16" of travel and a 62" front trackwidth. . .the I-beams are equal length with 24" between the pivot points and the radius arms are equal length and are 34.75" long. Maybe you could give me your input. . .

I know they aren't perfect or ideal. . .yet, this is a work in progress. If you would be willing to talk to me offline about this that would be great! Just let me know

There is a give and take with each. We have found it really does not matter with equal length beams with the average setup. Unless you are going to spend the money to do it right with full hydraulic ram steering, correct steering geometry with all new spindles with correct ackerman etc... then go with un-equal length beams and when you get to it then ad a single swing steering to reduce the bumpsteer. .

I'm have full control of everything. . .initially I was going to be stuck with the knuckle that's in the picture, but now the timeline has shifted a full year to the right so I have the time to work on designing knuckles that are for an I-beam set-up instead of a compromise of using the knuckles that we have. . .no full hydraulic on a buggy of this size (~350 lbs. without driver) but it will have swing steering. . .that was going to the next part that I started to work on so that I can tweak everything to minimize bumpsteer. . .I already plan on changing camber from -2* at ride height to somewhere between -0.5* and -1* camber at ride height. . .the original setting was a suggestion and the new range has been suggested after some others have seen the pic of the current set-up. What's your take on the camber settings? Caster is at 6* right now. . .

What is nice about a PROPERLY setup equal length system is you are in control of the complete setup. So yes you can reduce most of the bumpsteer to under 1/8" over 20+ inches of travel.

In most cases I see equal length beams are more of a buzz word then a need. I would also say that in most cases the people who have equal length beams should have stuck with un-equal length beams and spent their money on better parts through out there whole truck because they are on a limited budget.

Now Cameron and Heidi steel were on a mission to prove this point this year and they did with their Baja 1000 win and SCORE championship. They did this with a solid built truck and quality parts through out there build. They kept it simple and to the point of what is needed to WIN.

Thanks for posting up. . .I was hoping that you guys, Blitzkrieg, and Giant would hop into one of these discussions.

The pic's are of the buggy chassis with the I-beams, radius arm, and driver's side knuckle, followed by a head-on shot of the I-beam with the knuckle, and finally of the knuckle that I was going to use (not anymore) without the steering arm on it.

Thanks!