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    Posted: Jun/23/2011 at 1:31pm
Hello,
My team and I are working on a new suspension for next year. We are thinking about using trailing arms in the rear. Does anyone have any tips for figuring out the geometry? Thanks
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/23/2011 at 1:38pm

www.lmgtfy.com/?q=trailing+arm+geometry

study a vehicle dynamics book like Race Car Vehicle Dynamics or similar
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Red_Beard Quote  Post ReplyReply Direct Link To This Post Posted: Jun/23/2011 at 2:42pm
Originally posted by collinskl1 collinskl1 wrote:

www.lmgtfy.com/?q=trailing+arm+geometry

study a vehicle dynamics book like Race Car Vehicle Dynamics or similar


Here, let me help you out with this Big smile
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Jun/23/2011 at 5:27pm
NVM!


Edited by ErikHardy - Jun/30/2011 at 10:53am
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/23/2011 at 6:02pm
Originally posted by ErikHardy ErikHardy wrote:

Depending on how in depth you want to go but for the basics:
Keep the radius rod pivot points close to the cv joint pivots for minimal axle plunge
The shorter the length of the trailing arm, the more the wheelbase will change affecting axle plunge,heim joint misalignment, "bump steer", etc..
Make sure the dam thing fits inside the wheel
Be aware that your axles will be exposed to obstacles


Are you talking about 3link suspension? How can the radius rod pivot be close to the cv joints?

Ima confused...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Jun/23/2011 at 10:49pm
Jeremie, I was just refering to the arc motion of the axles in relation to the suspension.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote p.lewis Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2011 at 5:48pm
Originally posted by ghetoaid ghetoaid wrote:

Hello,
My team and I are working on a new suspension for next year. We are thinking about using trailing arms in the rear. Does anyone have any tips for figuring out the geometry? Thanks
 
We were pretty hard on you, but that was a bad question. No hard feelings.
 
Here's where you start doing your research, then ask more important questions:
 
Anybody else want to offer some of the staple threads for ghetoaid to use to catch up with the rest of us?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 4:31pm
Originally posted by jeiB jeiB wrote:

Originally posted by ErikHardy ErikHardy wrote:

Depending on how in depth you want to go but for the basics:
Keep the radius rod pivot points close to the cv joint pivots for minimal axle plunge
The shorter the length of the trailing arm, the more the wheelbase will change affecting axle plunge,heim joint misalignment, "bump steer", etc..
Make sure the dam thing fits inside the wheel
Be aware that your axles will be exposed to obstacles


Are you talking about 3link suspension? How can the radius rod pivot be close to the cv joints?

Ima confused...
Live Axle is the only way to go.  I've said it before, "There is no such thing as a good IRS (Independent Rear Suspension) for SAE Baja!"

Generally speaking you build the trailing arm just big enough to swing around the motor.  The incline of the arms in relationship to the CG affects weight transfer.  The shock motion ratio should be about 1:2 with about 33% sag at static ride height.  The stiffness of the connecting beam (twist arm) determines anti-roll.  The roll center will be located at the center of the axle.  No Jacking Force is generated so you'll be less likely to experience the joy of vehicle roll-over in a sharp turn.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 5:24pm
Akron, you haven't seen mine then :)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 6:00pm
Originally posted by CLReedy21 CLReedy21 wrote:

Akron, you haven't seen mine then :)

TTU using IRS “BLASPHEMY”.  Next you’re going to say you’ve converted to metric (aka the tool of the devil).

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Post Options Post Options   Thanks (0) Thanks(0)   Quote tp Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 7:05pm
Remind me again, how is there no such thing as a good IRS for a Baja car? This might have been true back in 2004 but the results from the last few year seem to say otherwise.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 7:56pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by CLReedy21 CLReedy21 wrote:

Akron, you haven't seen mine then :)

TTU using IRS “BLASPHEMY”.  Next you’re going to say you’ve converted to metric (aka the tool of the devil).



The gearbox is metric :)  All the other fasteners on the car are still standard.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote frinesi2 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/28/2011 at 8:43pm
No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 11:56am
Originally posted by tp tp wrote:

Remind me again, how is there no such thing as a good IRS for a Baja car? This might have been true back in 2004 but the results from the last few year seem to say otherwise.

Explaining why a live axle is better than an IRS in Baja is like Galileo explaining the earth is round to everyone that was just so sure it was flat.  It’s best I show you.  I have family in town 4th of July weekend but any other weekend you want me to come drive with you, I’m game.  Seattle isn’t too far away from Portland.  Maybe we can meet in the middle.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 12:14pm
Originally posted by frinesi2 frinesi2 wrote:

No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile

I saw a You Tube video of Laval going around a corner.  They even had a camera mounted on the car pointed at the rear tire.  Both rear tires cambered out of the turn.  I didn't like it for several reasons.

 

Granted the trailing link IRS you guys have been using is far better than double A-arm IRS.  But if you really look at the numbers, the increasingly rare Live Axle is still winning a disproportionally high number of competitions for a reason.  It's not just because they're stronger or easier to build.  The dynamics of a Live Axle are very appealing to this kind of race. Look at a MX ATV if you don’t believe me.

 
I'm not concerned with TTU.  I need to get Akron back on the straight and narrow.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 12:29pm
I think we are off topic now. We are supposed to be talking about trailing arm geometry!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Red_Beard Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 1:24pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by tp tp wrote:

Remind me again, how is there no such thing as a good IRS for a Baja car? This might have been true back in 2004 but the results from the last few year seem to say otherwise.

Explaining why a live axle is better than an IRS in Baja is like Galileo explaining the earth is round to everyone that was just so sure it was flat.  It’s best I show you.  I have family in town 4th of July weekend but any other weekend you want me to come drive with you, I’m game.  Seattle isn’t too far away from Portland.  Maybe we can meet in the middle.



Elbe Hills is probably the closest you'll get to the middle.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tp Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 1:49pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Explaining why a live axle is better than an IRS in Baja is like Galileo explaining the earth is round to everyone that was just so sure it was flat.  It’s best I show you.  I have family in town 4th of July weekend but any other weekend you want me to come drive with you, I’m game.  Seattle isn’t too far away from Portland.  Maybe we can meet in the middle.


I've actually been living in Portland since March. Feel free to come visit whenever!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 2:13pm
Originally posted by jeiB jeiB wrote:

I think we are off topic now. We are supposed to be talking about trailing arm geometry!

It's more on topic than you think.  When building a trailing arm you've got options of Live Axle or a De Dion tube.  Both are dependent trailing arm type suspension.  Part of my there are no good IRS in Baja argument is I believe people who think they are building independent trailing links are actually making complicate dependent De Dion tube trailing arm suspensions.

They're doing the right thing by accident.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:16pm
Originally posted by frinesi2 frinesi2 wrote:

No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile
De Dion tube is a French dependent trailing arm suspension

Three of the four teams you praised for excellent IRS are French Canadian.

Galileo sounds like a French name.

Oh my, you praise a dependent suspension as the best IRS in SAE Baja.

I just blew your mind.

 

I’m re-naming Live Axels as Freedom Axles.  Do your patriotic duty and think about it while eating some free Freedom Fries.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:31pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by frinesi2 frinesi2 wrote:

No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile
De Dion tube is a French dependent trailing arm suspension

Three of the four teams you praised for excellent IRS are French Canadian.

Galileo sounds like a French name.

Oh my, you praise a dependent suspension as the best IRS in SAE Baja.

I just blew your mind.

 

I’m re-naming Live Axels as Freedom Axles.  Do your patriotic duty and think about it while eating some free Freedom Fries.



Once again, for those in the cheap seats...

Trailing Arm =/= Trailing Link

Trailing Arm


Trailing Link (Aka: 3 Link, Drag Link, Multi-Link Semi Trailing)  Note:  We actually have 4 links because we have adjustable toe.  Most other teams do not.






Edited by CLReedy21 - Jun/29/2011 at 3:32pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:39pm

Do you have any kind of anti-roll bar linking the right & left side together?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:41pm
We did for Birmingham to keep the float off the ground, however the system was designed with the roll stiffness built into the linkages so that you don't need a sway bar, which it didn't have in Kansas.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:51pm
Originally posted by CLReedy21 CLReedy21 wrote:

We did for Birmingham to keep the float off the ground, however the system was designed with the roll stiffness built into the linkages so that you don't need a sway bar, which it didn't have in Kansas.

I believe when people add an anti-roll or sway bay they could be accidently acting like a De Dion tube, effectively transforming their IRA into a stealth dependent trailing arm suspension.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:53pm
Could be, but the TTU version of the Trailing Link is fully independent.  The only reason that we even put sway bar provisions on it was because the body roll was letting the float drag under hard cornering.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 3:56pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by CLReedy21 CLReedy21 wrote:

We did for Birmingham to keep the float off the ground, however the system was designed with the roll stiffness built into the linkages so that you don't need a sway bar, which it didn't have in Kansas.

I believe when people add an anti-roll or sway bay they could be accidently acting like a De Dion tube, effectively transforming their IRA into a stealth dependent trailing arm suspension.


Ok, NOW I understand what you are rambling about...approaching the behavior of a dependent suspension using an ARB on an independent suspension. An ARB+independent allows for more adjustability...not just the extreme.

But yes, you are right with people designing "stealth" dependent suspension to SOME degree.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 4:06pm
Originally posted by tp tp wrote:

Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Explaining why a live axle is better than an IRS in Baja is like Galileo explaining the earth is round to everyone that was just so sure it was flat.  It’s best I show you.  I have family in town 4th of July weekend but any other weekend you want me to come drive with you, I’m game.  Seattle isn’t too far away from Portland.  Maybe we can meet in the middle.


I've actually been living in Portland since March. Feel free to come visit whenever!

How about the weekend of July 23rd.  Elbe Hills, where ever, doesn't matter.  I've just got the cars back together and want to ride.  I'll let you try my trailing arm out for a spin in exchange for taking your car for a spin.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote tp Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 4:08pm
I no longer feel bad about derailing this thread since we haven't seen or heard from the guy that started it in a while.

Anyways- how about Tillamook State Forest? It'd be a bit of a drive for you but it is some of the best rock crawling and trail riding you can do.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dillon_b12 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 4:17pm
Akron, why don't you use the PMs to set up the rendezvous?  Let's try to keep this about trailing arms...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 4:51pm
Originally posted by jeiB jeiB wrote:


Ok, NOW I understand what you are rambling about...approaching the behavior of a dependent suspension using an ARB on an independent suspension. An ARB+independent allows for more adjustability...not just the extreme.

But yes, you are right with people designing "stealth" dependent suspension to SOME degree.
 

You’re starting to get it.  One you take into account speed, geometry, how sharp you want to turn, how much you don’t want to roll over, etc. I’ve come to the conclusion of why would you build an IRS that acts a lot like a Live Axle trailing arm when you can build a Live Axle trailing arm that acts a little like an IRS.

Twist arm trailing arm with Live Axle work great for Baja.  They do pretty much the same thing as a locked up IRS but are a heck of a lot simpler and reliable.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tp Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 6:04pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by jeiB jeiB wrote:


Ok, NOW I understand what you are rambling about...approaching the behavior of a dependent suspension using an ARB on an independent suspension. An ARB+independent allows for more adjustability...not just the extreme.

But yes, you are right with people designing "stealth" dependent suspension to SOME degree.
 

You’re starting to get it.  One you take into account speed, geometry, how sharp you want to turn, how much you don’t want to roll over, etc. I’ve come to the conclusion of why would you build an IRS that acts a lot like a Live Axle trailing arm when you can build a Live Axle trailing arm that acts a little like an IRS.

Twist arm trailing arm with Live Axle work great for Baja.  They do pretty much the same thing as a locked up IRS but are a heck of a lot simpler and reliable.

Now I get what you're saying too. I got all bunched up thinking you were saying IRS didn't have any place in Baja. Sometimes I really just want to put my flame hat on and go to town...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 7:38pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by frinesi2 frinesi2 wrote:

No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile

I saw a You Tube video of Laval going around a corner.  They even had a camera mounted on the car pointed at the rear tire.  Both rear tires cambered out of the turn.  I didn't like it for several reasons.


Which car did you see? Probably the 2010, which had stiffness issues on the rear suspension...
The camera was mounted on the front upper A-arm, visual shows special effect then
Don't forget that tire are far from stiff so you see a lot of tire compliance too.


Edited by Nick914 - Jun/29/2011 at 8:08pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 7:59pm
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by frinesi2 frinesi2 wrote:

No such thing as a good IRS for a Baja SAE car?

I think we, Laval, TTU, ETS, and Sherbrooke have proven that trailing link isn't too shabby.

I, for one, will not be changing, but I welcome you to convince TTU to change to live axle, Chris Evil Smile
De Dion tube is a French dependent trailing arm suspension--  French engineering is not something I want to rely on

Three of the four teams you praised for excellent IRS are French Canadian.-- 5 teams were mentionned ;)  (UMBC guy included himself)

Galileo sounds like a French name.-- Gallileo was Italian

Oh my, you praise a dependent suspension as the best IRS in SAE Baja.-- You just reversed everything

I just blew your mind.--  Yours might as well be mixed up :P

 

I’m re-naming Live Axels as Freedom Axles.  Do your patriotic duty and think about it while eating some free Freedom Fries.



Edited by Nick914 - Jun/29/2011 at 8:11pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 8:11pm
Something I just realized.  Of the 5 teams mentioned (UMBC, Laval, ETS, Sherbrooke, and TTU), only 1 uses a sway bar...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Nick914 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 8:16pm
Originally posted by CLReedy21 CLReedy21 wrote:

Something I just realized.  Of the 5 teams mentioned (UMBC, Laval, ETS, Sherbrooke, and TTU), only 1 uses a sway bar...

You and sherbrooke, no?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote CLReedy21 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 8:21pm
Only Sherbrooke.  We took ours off after Birmingham.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote frinesi2 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/29/2011 at 10:14pm
I think I've seen that video/picture too. Nick, your suspension is similar to ours in that it seems to camber out of turns, whether from geometry or deflection.

Doesn't really seem to make much of a difference, though.

The De Dion tube is a fantastic suspension . . . for smooth asphalt.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 8:57am
Originally posted by Nick914 Nick914 wrote:

Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

I saw a You Tube video of Laval going around a corner.  They even had a camera mounted on the car pointed at the rear tire.  Both rear tires cambered out of the turn.  I didn't like it for several reasons.

Which car did you see? Probably the 2010, which had stiffness issues on the rear suspension...
The camera was mounted on the front upper A-arm, visual shows special effect then
Don't forget that tire are far from stiff so you see a lot of tire compliance too.
I don't recall the original video I saw but the 2010 Laval car definitely cambered both rear tires out of the turn (The front tires too).  Not good.
 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 9:11am
I think you are referring to this

http://www.youtube.com/watch?v=vSwB-lkywb8&feature=player_detailpage#t=146s
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 9:12am
Originally posted by CLReedy21 CLReedy21 wrote:

Something I just realized.  Of the 5 teams mentioned (UMBC, Laval, ETS, Sherbrooke, and TTU), only 1 uses a sway bar...
Then only 1 has a decent IRS. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 9:30am
Originally posted by jeiB jeiB wrote:

I think you are referring to this

http://www.youtube.com/watch?v=vSwB-lkywb8&feature=player_detailpage#t=146s
Yeah that's the video.
 
Camber control is one of the reasons people claim IRS is better that Trailing arm with Live Axle.  When I saw this video I shouted BS.  I should look and someone else's videos.  I bet more teams have this issue. 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jeiB Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 10:07am
Originally posted by Akron 1998 to 2004 Akron 1998 to 2004 wrote:

Originally posted by CLReedy21 CLReedy21 wrote:

Something I just realized.  Of the 5 teams mentioned (UMBC, Laval, ETS, Sherbrooke, and TTU), only 1 uses a sway bar...
Then only 1 has a decent IRS. 

You're so funny!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 10:20am
Akron, so if only 1 team has it right, the rest have crapola? They all have very good results but I'm sure thats besides the point
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 10:54am
Originally posted by ErikHardy ErikHardy wrote:

Akron, so if only 1 team has it right, the rest have crapola? They all have very good results but I'm sure thats besides the point

I was personally involed with three 1st place and one 2nd place overall finish with the trailing arm live axle design.  One reason why I didn't experience four 1st place finishes is because the design judges are all pro IRS fanatics and gave our car horrible static design scores (every year).  I don't understand why we had to defend the design choice so much.  The dynamic results speak for themselves.

I don’t really buy the argument that 2004 was such a long time ago, cars are so much better today (sure they are!).

There are just so many IRS Baja cars that a few are bound to get lucky.

Not everyone can design a trailing arm as good as we did.



Edited by Akron 1998 to 2004 - Nov/16/2011 at 1:04pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 10:59am
Is there a baja equivalent of a highschool hero?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dillon_b12 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 11:10am
2004 wasn't that long ago, but Baja has changed drastically since about '07.  Just go through some albums and look at the cars.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote P-L Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 11:23am
...Laval got 3 1st place, 1 2nd and 1 3rd with this suspension...with a couple of S&T and endurance 1st place....it's probably not THAT bad...
as you said, the dynamic results speak for themselves...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote collinskl1 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 11:39am
And really, we're on dirt.  Vehicle dynamics are cool and all, and I believe they absolutely have their place in baja... but a white knuckle grip and a generous use of the go pedal can make any robust car look pretty good.  Driver skill, practice, and luck may have just as much to do with doing well as suspension type.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ErikHardy Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 12:04pm
I'm surprised nobody has mentioned the drivetrain loss of IRS vs. the ol solid axle..
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Akron 1998 to 2004 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/30/2011 at 12:13pm
Originally posted by ErikHardy ErikHardy wrote:

I'm surprised nobody has mentioned the drivetrain loss of IRS vs. the ol solid axle..

People don't really want to know the advantages with solid axle.  They don't care, IRS is "COOL"!  Its like trying to convincing someone with an I-Phone that there might be something better.

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