Mitsubishi Evo almost coming off track...

[wwgkd]

What cars are you basing that opinion on ?
Modifcations of existing frames produces as capable vehicles IF they are done properly.
Ford, BMW, Seat, Skoda, Renault, Peugeot, Lotus have been doing it successfully for decades

BTW, a Lotus Exige ran in the British Rally cross championship and didn't fare well Rigidity and strength arent' one and the same in chassis design.




Oh, hehe, that's ok, I'm not trying to argue with you, then. I wrote hells yeah because I was up drinking with friends and had just had an argument with them over basically the same thing. Kind of a random thing.

I like the SRT-4 because it was the 0-60 per dollar king, and did some other things, too. If I had the money for an Evo, I would not choose the SRT-4 over it, but I wouldn't take an evo, either. You'd have a hard time convincing me something with 4 seats is a true sports car, and no chance at 4 doors.

[/QUOTE]


Modifications of existing frames are cheaper than designing an entirely new chassis, which is why so many companies do it. It makes financial sense, otherwise the project may not be feasible; just because it works well doesn't mean it couldn't be better, especially when you start having $40,000 cars built off of something that started life at $15,000.

Rally racing is different, as I've been saying all along. When you don't have the traction, rigidity isn't as important as it is when trying to get maximum traction on asphault. Also, frame design needs to be very different if you're planning on getting airborne or other things like that. But the car in question was on an asphault track with no chance to get air. It is not unusual at all to see Evo's lifting a tire, but when's the last time you saw a Lotus/Viper/'Vette/Ferrari doing that?

[Matra et Alpine]

Modern rallying tarmac sections are MUCH more demanding that any race track requiring even more in chassis and suspension development.

re lifting a wheel, What you're talking about there is WEIGHT, not chassis

[nota]

re lifting a wheel, What you're talking about there is WEIGHT, not chassis

I thought suspension tune, as in roll stiffness, was the big factor

[Matra et Alpine]

I thought suspension tune, as in roll stiffness, was the big factor

yeah, but WHY does it lift ? Because there is mass pushing out under the cornering forces causing much higher forces on the suspension and compression leading to body roll beyond what the suspension can provide drop for.

Of course, lifting a wheel is NOT a major problem, inside wheels on fast cornering are nto doing very much

[Matra et Alpine]

oooh, it's not fully lifted it's wheel yet, but I just loved this pic

[Coventrysucks]

Some Reliant Robin

That's nothing compared to the mighty Clio - so much torque it is "twisting the chassis" under braking... imagine what will happen when he floors it on exit - it'll look like a corkscrew.

That'll teach them for not doing it the American Way™!

And it's on fire, cheap econo-rubbish...

[Niko_Fx]

Jesus its an inside joke, its not like I called your children ugly.

That wouldn't upset me as much as saying that an EVO sucks

[Matra et Alpine]

That's nothing compared to the mighty Clio - so much torque it is "twisting the chassis" under braking... imagine what will happen when he floors it on exit - it'll look like a corkscrew.

That'll teach them for not doing it the American Way™!

And it's on fire, cheap econo-rubbish...

You missed sarcastic smiley in your comments
Some won't get it

Like all FWD racers, the rear is so stripped out that their is very little weight and they turn in well putting all the mass on to the outside front wheel !

[wwgkd]

Modern rallying tarmac sections are MUCH more demanding that any race track requiring even more in chassis and suspension development.

re lifting a wheel, What you're talking about there is WEIGHT, not chassis

A combination of suspension, weight and chassis. And yes, I did mention weight as being an important part of chassis design. Thus the 150 lb Lotus frame (designed for that car, not to be a 4 door family car.)

The chassis has to be able to support the forces generated. Obviously, if one corner compresses 3 inches, the chassis torques 2 inches and the opposite corner corner can only drop 3 inches, the tire is off the road.

Plus there is a huge difference between a front tire being off the ground about an inch (possible after one of those bumps helped it along) and the rear tire being off the ground 5 inches. And yes, one tire off the ground does make a difference. Not only is the traction from that tire important (every little bit helps,) but the force load on the suspension is different if that inside tire is still able to bear weight and reduce the load on the outside suspension. In addition to that, it effects the cars attitude and ability to settle quickly when transitioning from that corner.

oooh, it's not fully lifted it's wheel yet, but I just loved this pic

The Caterham is a kit car based off of something made 50 years ago, that doesn't really impress me; same basic argument. I don't know what the race car is, got any info on that?

You say that racing a Lotus in rally doesn't work very well. If you put a rally car out there with the F430 GTC in an FIA GT race the rally car will get owned. If you put one in the Baja races, it will also get owned. That's why they don't race them there. Vehicles are designed for what they're used for. You're saying that they rally car spends more time in development, which I don't find true at all. If nothing else will convince you, look at the money put into the two racing programs. Time + effort = money.

You keep trying to confuse the issue by comparing rally racing to what a Lotus or Viper is made for. If a vehicle were to be designed for rally racing from the ground up, it would almost certainly be better at it (more capable) than a suped up 4-door. Which is what I've been saying all along.

That wouldn't upset me as much as saying that an EVO sucks

LOL. All right, good call dude. It's definitely not my kind of car, but as long as you love it, I'm not calling you wrong for it.

[P4g4nite]

If a vehicle were to be designed for rally racing from the ground up, it would almost certainly be better at it (more capable) than a suped up 4-door. Which is what I've been saying all along.

What you were saying all along is that the Evo chassis is bending a matterof inches while cornering, that`s why everyone thinks you are a clown.
The Evos photo`d by the OP lifting tyres have seam welded chassis and roll cages. They are plenty rigid, if they body twisted enough to let the wheels off the ground the doors would be popping off.

The Caterham is a kit car based off of something made 50 years ago, that doesn't really impress me; same basic argument.

It is designed to look like the old racer, it has a modern chassis, modern suspension, modern brakes and modern tyres.

[Jack_Bauer]

@ wwgkd

I suppose the fact that this Ferrari F1 car with its wheel off the ground in Malaysia last week means it has some flexy, badly designed chassis too?

[wwgkd]

What you were saying all along is that the Evo chassis is bending a matterof inches while cornering, that`s why everyone thinks you are a clown.
The Evos photo`d by the OP lifting tyres have seam welded chassis and roll cages. They are plenty rigid, if they body twisted enough to let the wheels off the ground the doors would be popping off.
It is designed to look like the old racer, it has a modern chassis, modern suspension, modern brakes and modern tyres.

Dude, they do flex. Manufacturers do measure it. I'm not saying one tire off the ground a half inch is all frame flex. But when one tire is off the ground 5 inches, yes, that has something to do with it. We're working on a project right now where we're analyzing how much that happens. This may be news to you, but even the best materials will flex under pressure, and that kind of pressure is found in cars cornering on race tracks. If they didn't flex there would be no point at all in designing newer stiffer frames, would there? And yet what are car manufacturer’s constantly doing? Building better frames. You have a good reason why they're doing that if the existing frames are impervious to all forces?

When I said it's an old car and the same argument applies, I meant that when you take an old design (or cheap, in any case not designed to handle larger forces) and increase the force load through modern tires, suspension, brakes, etc. it will not handle them as well as something designed from the ground up. And when you beef them up with extra supports, you're finding an imperfect solution which adds weight in a less than optimal manner, where something designed from the start is much more efficient and stiffer. We're using a Caterham as one of our project focuses and the design of the frame has barely changed since the original. The biggest changes are added supports and materials.

Materials flex in all situations where forces are applied.

[wwgkd]

@ wwgkd

I suppose the fact that this Ferrari F1 car with its wheel off the ground in Malaysia last week means it has some flexy, badly designed chassis too?

Like I stated previously, 5 inches is crazy and cannot be accounted for in suspension travel, or horizontal flex of components. Show me an F1 car or other car along those lines 5 inches off the ground.

On flat ground there is only so much suspension and subframe components can flex to account for that kind of difference (obviously where the anti roll bars come into play.) If there was no flex in any frame or subframe, then there would be no need for constant R&D on the subject of stiffer and stronger frames.

[2ndclasscitizen]

We're using a Caterham as one of our project focuses and the design of the frame has barely changed since the original. The biggest changes are added supports and materials.

Old design =/= bad design. And what Caterham are using? The base models might be using very basic suspension components, but look up what's running underneath a CSR or R-series Caterham.

[P4g4nite]

Dude, they do flex. Manufacturers do measure it.

Not in inches.

Materials flex in all situations where forces are applied.

I never claimed they don`t, I do claim that the Evo body isn`t flexing in inches during cornering.

I meant that when you take an old design (or cheap, in any case not designed to handle larger forces) and increase the force load through modern tires, suspension, brakes, etc. it will not handle them as well as something designed from the ground up.

Thank you captain obvious, but this still doesn`t mean that a modified version of an existing design can`t work just fine. Evos, Imprezas and Renault`s `Cup` cars are examples of this.
With the history of rallying both Subaru and Mitsubishi have, I`m sure at least some consideration is given during design for the performance oriented examples

Like I stated previously, 5 inches is crazy and cannot be accounted for in suspension travel, or horizontal flex of components.

What is this 5 inches you keep talking about?