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And your country elected to no longer help Germany financially prop up the rest of the EU. What's your point? We're talking suspension - not taking cheap shots.

I'd typically close the thread at this point but it's been a good enough discussion that I really hate to do so. Please cut it out and keep it civilized.

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-Andrew
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Agree.

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My build: http://www.locostusa.com/forums/viewtop ... 18&t=13096


You can build the most awesome thing in the world but at some point, an 80yr old man in a crx is probably going kick your butt on the track... don't ask me how I know.

Sam Is Right! I am trying to draw him out in any way I can. He has some brains and just won't share, dammit.

I agree this has been a very informative and sometimes entertaining thread but sam you have stepped over a line with that one and shown everyone how much of an ignorant schoolyard bully you are.
If you cant explain/argue without getting into personal or national insults you have no place here as far as I am concerned.

yes but that doesn't make you a troll.

In Internet slang, a troll (/ˈtroʊl/, /ˈtrɒl/) is a person who sows discord on the Internet by starting arguments or upsetting people, by posting inflammatory, extraneous, or off-topic messages in an online community (such as a newsgroup, forum, chat room, or blog) with the intent of provoking readers into an emotional response or of otherwise disrupting normal, on-topic discussion, often for the troll's amusement.

Sams original comical roll statement does by definition but we all ignore that since it has started a good conversation.

But this has digressed enough. Moving on.

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My build: http://www.locostusa.com/forums/viewtop ... 18&t=13096


You can build the most awesome thing in the world but at some point, an 80yr old man in a crx is probably going kick your butt on the track... don't ask me how I know.

Yes, moving on.

In my last post with pictures, I found the rotational force on the front end and the corresponding resisting roll moment. Now we have them at both ends and can determine how much weight we want to transfer longitudinally. I think it's all there.

I especially would like a critique on Exhibit 5.

This car example gives you a correlation, but not a causation. I think the vertical movement of several inches is a huge issue, but it does not also point the finger at the lateral movement. The lateral movement may also be an issue, but it may not be a root way of looking at it. In order for your prior statements to be true, you must show that all lateral movements cause bad results.

If I look at things like the line of force from the contact patches, sometimes lateral movement of the roll center indicates bad things, but sometimes it does not. Vertical movement always indicates bad things, not only the angles of the force lines but also the magnitude of the moments.

In order to make blanket statements about lateral roll center movement, you need to describe the problems with a simple case like a roll center at ground 100 meters to the side of the car...

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

What a 'clever' mind, to so deftly avoid being 'tricked' into such atrocities.

Well, at least now nobody can dispute your mastery of what a 'troll' is.

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-Justin

"Orville Wright did not have a pilots license." - Gordon MacKenzie

My point, as you've so very elegantly demonstrated by your example, is that there's a difference between doggedly supporting a concept that's blatantly dumb, and cutting your losses and looking for a better way of doing things.

Add yet you just continue with the same wearisome approach to interacting with people on this forum. Insult, if that didn't work more insults... All the while being unable to articulate or demonstrate even rudimentary support for your position outside of you once drove a car with so many problems you considered it a danger to life as we know it.

I think the dumb concept here is your choice in how you make a technical case for your point of view...

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Most sensible post in the whole thread:

i am still waiting to see the caterham suspension geometry. anyone have it?

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My build: http://www.locostusa.com/forums/viewtop ... 18&t=13096


You can build the most awesome thing in the world but at some point, an 80yr old man in a crx is probably going kick your butt on the track... don't ask me how I know.

You can look for a paper that was published by Lotus engineering for an update they did on the Caterham car. I don't think I have a copy. You can see that their front suspension uses arms a little more nearly parallel than some, but they are not equal length. Perhaps not unlike the advice you got from Palatov...

Back to roll centers. I don't have any trouble thinking cars are 3d problems, I do struggle to see how you cannot demonstrate the issues with 2d diagrams though. If nothing is changing in the 2d diagrams, one would think the 3d problems are not changing either. How would you even determine a roll axis without doing a 2d drawing to find the roll centers?

I am also curious how one determines that the Mitchel software rolls the car about a central point at ground level. I can imagine the car is displayed that way, but that's not the same thing. Is the ride height incorrect?

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

I assuming by the responses, the caterham roll centers move quite a bit latterly correct?

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My build: http://www.locostusa.com/forums/viewtop ... 18&t=13096


You can build the most awesome thing in the world but at some point, an 80yr old man in a crx is probably going kick your butt on the track... don't ask me how I know.

Wrong.

The rear roll centre on the Caterham is pretty much fixed at the centre of the A-frame that locates the de Dion, of course.

The analysis that Horizonjob refers to states that the front roll centre migration on the original design was 0.9mm (that's three and a half thousandths of an inch, to you guys - and you can be sure that that didn't happen by accident!). It doesn't quote a figure for the finalised geometry on the updated (CSR) design, but states that target was <10mm and refers to a couple of design options that achieve 3.6 and 4.1mm respectively (call it 1/6") at maximum roll.