The relative benefits of a pull rod suspension

[RacingManiac]

Tom, i purposely over exaggerated that post. But to be serious we have a resident Honda F1 car with gearbox. If the bolting pattern of the engine matches the box it will fit, clutch and shaft heights being the same.
A 2011 Torro Rosso gearbox will fit any 2011 Ferrari engine becuase it was designed around the F150 engine. That's what they are supplied with Agree?
I was using this to debunk the packaging myth.

Its a myth now too huh? Yes STR uses Ferrari engine with a gearbox designed to fit the engine. Does the STR have everything else supplied by Ferrari too? Do they design stuff with the exact same trade off as Ferrari? AFAIK(as told by people working on the Virgin car last year) teams using a supplied engine get pretty much just the engine, packaging information and some baseline engine map. Teams are free to tune it themselves, design their own cooling system, exhaust and all the auxiliaries. I am assuming here that its no different from how STR works with Ferrari. STR certainly doesn't share the rest of the Ferrari package so how can you claim that Ferrari is afraid of going Pullrod when STR can do it. Keep in mind also not more than a few years ago that STR(and IIRC, Sauber also) were having issue with cooling of their car and having the engine blowing up constantly, whereas Ferrari were have much less of an issue with their own motor.

But hey, all the rest of the F1 cars aside from aero are just a few bolts, some bearing and some gears right? How hard can they possibly to design that why F1 teams spends hundreds of million on some simple work....

[ringo]

Calm down.
Engine development freeze for the past 3 or 4 years. Countless gearbox designs fitted to that 056 engine.

A Torro Rosso gear box is already mated to a Ferrari type 056 engine, the same exact thing used in the f150 and Sauber C30. There is nothing you can do to change that fact.

Your post is almost pointless; talking about radiator cooling and engine maps, what's that got to do with the gearbox fitting the engine?

Stop focusing on attacking me please and stick to the topic. The dust settled and we were in for a some insight from Dave W.

[DaveW]

Were these torsion bar suspensions ?

One torsion bar, one coil over.

I think theoretically a lower COG offers better tyre wear.

Tyre wear or otherwise, it is generally a good idea to shoot for a low c.g. height. Your statement, however, implies that a pull rod suspension necessarily lowers the c.g. height. Perhaps it does, perhaps not. It does, however, illustrate the Fear Factor in a small way (critics jumping to conclusions based upon assumptions, rather than facts).

That's what i think this is all about with ferrari, pressure to perform and be reliable.

Forgive me, but I don't think Ferrari is unique in that respect.

In my view, Ferrari has shown the courage to follow engineering logic in its F150. The 2011 season will test that logic, of course. Will they be slower than all the pull rod vehicles? Probably not.

[RacingManiac]

Calm down.


Your post is almost pointless; talking about radiator cooling and engine maps, what's that got to do with the gearbox fitting the engine?

The point is that nothing with the "myth" of packaging is stand alone. How things are position and where they sit affects how things function. Nothing stand alone by itself in anything when its now installed in a physically constraining environment. On a test bench you can make every parts function by themselves, but in a intergrated assembly, especially in one that is limited in space like a F1 car, nothing can be designed without considering everything else also sitting in that space. And since every teams are working with different sub systems of differing origin(despite the fact that in the case of STR and Ferrari, they share a common engine), the design considerations of other subsystems will lead to different design solution. Be it as pullrod/pushrod, or designing cooling that may or maynot satisfy the need to sufficiently cool the given motor....

[Jersey Tom]

In my view, Ferrari has shown the courage to follow engineering logic in its F150. The 2011 season will test that logic, of course. Will they be slower than all the pull rod vehicles? Probably not.

This. x100.

[ringo]

In my view, Ferrari has shown the courage to follow engineering logic in its F150. The 2011 season will test that logic, of course. Will they be slower than all the pull rod vehicles? Probably not.

They wont be slower than all pull rod teams. There are a few really good features in the front bodywork of the F150. And going by the momentum from last year they can still be at the top.
It doesn't justify the choice though. A car can still be a winner with a suboptimal feature. HRT beat Virgin last year for some reason, it doesn't mean virgin's car has trivial features. Too many factors to consider.

But i would like to believe the other 10 teams were logical in their choice as well.


You mentioned a lower installation stiffness on these front pull rod cars, why is that?

[myurr]

It doesn't justify the choice though. A car can still be a winner with a suboptimal feature. HRT beat Virgin last year for some reason, it doesn't mean virgin's car has trivial features. Too many factors to consider.

And yet it is all those other factors that you refuse to consider in consideration of the optimal choice of suspension for each team. With their chosen set of compromises pull rod is optimal for Red Bull, push rod for Ferrari - why is that so hard to understand? For all we know Ferrari's cooling requirements wouldn't allow for as tight a rear end as the Red Bull and so their push rod layout may in fact be the better layout within their design parameters.

You also seem to believe that the Red Bull solution is optimal just because they won last year. All that really means is that they did an overall better job than everyone else - given 10 years to optimise a design to last years rules there is no guarantee that the design would be identical to the 2010 Red Bull or even have a pull rod suspension. For all we know Ferrari's layout may have more inherent potential, they just didn't do quite as good a job of unlocking it.

[PlatinumZealot]

~And the wheel... goes round~

[Formula None]

It does go round indeed, certain members feeling no shame in forfeiting all of their credibility. Keep on spinning, then. The premise of this thread seems to remain:

-Suspension design is but one of many aspects of race car engineering, with many factors that are optimized and compromised during the design process. This process may lead you to a pull or pushrod layout, or something else entirely.

-Ringo and smirk say pullrod suspensions are always superior in all circumstances, have no flaws relative to other suspensions designs, and is guaranteed to make your car faster.

Not too difficult to draw conclusions from the two motions put forth. I'll try to enjoy seeing this thread on the front page for the rest of the season.

[ringo]

It's tempting to respond. Because we have too many pages of the same thing, it makes a potentially quality thread a bag of bickering.

I give up!!


Oh my look on all the flaws, so many compromises that the push rod doesn't have to make.
The flaws relative to push rod are there, i don't know'em but they're there!!!

[myurr]

That Red Bull represents one solution, one that happened to win last year. Are you claiming it's perfect?

In another thread you yourself point out that Red Bull have fitted a wider fuel tank and elongated the gear box allowing for that shape of side pod - is their tight rear down to the pull rod or the angle of the rod itself. Would a push rod not fit on top of their gearbox in that 2011 design now that it's taller in the centre?

Just because the rear of that car looks good to your CFD capable eyeball, it doesn't mean it's the optimal solution. It may cause upstream compromises due to the packaging of the internals, such as the fuel tank, that mean a different layout and less tight rear result in a better car. What if it's more optimal for the exhausts to be closer to the centre of the car where a pull rod interferes but a push rod does not? What if the rear of the Red Bull is curved too tightly for some conditions and suffers from separation of the air flow, such that a slightly less compact rear actually performs better across the whole range of conditions?

[Tim.Wright]

I give up!!

I'm not a religious man but. Haleujah...

[ringo]

That Red Bull represents one solution, one that happened to win last year. Are you claiming it's perfect?

Nope, but you still can't tell me a weakness that it has to push rod.

In another thread you yourself point out that Red Bull have fitted a wider fuel tank and elongated the gear box allowing for that shape of side pod - is their tight rear down to the pull rod or the angle of the rod itself. Would a push rod not fit on top of their gearbox in that 2011 design now that it's taller in the centre?

It would fit, but it would have to be covered with bodywork, which would interfere with the airflow, check the 2010 mercedes benz with the bumps on the gearbox.
The gearbox would automatically have to be wider as well to fit the heave springs and dampers. So basically you would have a huge lump on the car, and they would have to find openings to send cooling air.

Just because the rear of that car looks good to your CFD capable eyeball, it doesn't mean it's the optimal solution. It may cause upstream compromises due to the packaging of the internals, such as the fuel tank, that mean a different layout and less tight rear result in a better car.

Now, you are fishing for compromises. The redbull's tank is not short becuase of the pull rod. Mclaren and mercedes have long narrow tanks. The tank is short becuase they want it to be that way.

What if it's more optimal for the exhausts to be closer to the centre of the car where a pull rod interferes but a push rod does not? What if the rear of the Red Bull is curved too tightly for some conditions and suffers from separation of the air flow, such that a slightly less compact rear actually performs better across the whole range of conditions?

You see your bias? You are assuming other teams overlook pretty straight forward wind tunnel stuff, but ferrari is the only who who got it just right.
I am sure the teams have analyzed the air flow around the side pods ahead of the gearbox. RB6 had the most down force last year for a reason.

[Ciro Pabón]

I give up!!

Oh, please. Why are you giving up so easily? It's only 20 pages. We expected a more vigorous fight from you, let's say, 20 pages more. What if Ferrari proves everybody is wrong?

Black or white?

It is what it is.

If what you feel is,
Truly is.
And what you're feeling is comes true.
Chances are your is
Truly is true
The ratio is ten to two

It is what it is.

Oh, no, no, no, no, no, dear ringo. This is engineering, not social sciences. Here you have some examples I give in class:

Is the glass half empty or half full? Engineering response: you have half a glass more than what is needed (for the water it contains). So, you can cut and throw away half a glass. Actually, in racing, you HAVE to.

What was first, the egg or the chicken? Engineering response: the egg was invented loooong way before the chicken. The ancestors of chickens were born from eggs. When they ask you "Well, then where did come the first egg?" you can answer: "Duh, from a dinosaur. Are you actually against evolution?".

Is a zebra coat white on black or black on white? Engineering response: a zebra is black with white stripes. Ingenuous people (probably architects or physicists) used to think that a zebra has black stripes on a white coat because the underbelly is white. However an engineer discovered that a zebra embryo is black in the beginning and develop white stripes later in pregnancy.

... although I agree with the "it is what is is" part, but I'm never satisfied until I find an answer to what exactly it is.

So, my suggestion, let's revive this discussion after we have some numbers taken from telemetry, to know if pull or push rod suspension gives you an advantage this year. We CAN know.

[Formula None]

Is a zebra coat white on black or black on white? Engineering response: a zebra is black with white stripes. Ingenuous people (probably architects or physicists) used to think that a zebra has black stripes on a white coat because the underbelly is white. However an engineer discovered that a zebra embryo is black in the beginning and develop white stripes later in pregnancy.

The stripes offer a performance advantage over other ungulates, as in race cars.