237 replies to this topic

[Fat Boy]

Can anybody come up with a rational set of axes for the graph in http://www.gordonkir...t_is_no235.html?

mph vs metres seems to give me 300 hp, but that seems a bit bizarre.

The X-axis is labeled feet (where it says distance 3264.184 ft.). Since we're in the US, the speed basically has to be MPH. That and the Dallara hits terminal speed in road course trim somewhere around 170 mph. Do the acceleration numbers not work out? I haven't ran them. I guess you'd have to use a very low weight and a very low drag.

It's funny that they use the Dallara as the road course benchmark. They are pretty unspectacular to watch on a road course. Ya, they can boogie on an oval, but on at a proper road course (Watkins Glen, for instance) they look a little ponderous. Too much tire and not enough power. Champ Car had only 100 more HP, but because of the turbo the powerband was much wider.

[Dmitriy_Guller]

Would the Delta wing car have different trims for ovals and road courses, given that it doesn't have wings? If not, then this graph actually doesn't look promising at all.

[cheapracer]

In fact I don't believe I've heard so many frivolous, uninformed comments about motor racing in many years and it's sad to see many people who have no engineering or technical knowledge so easily dismiss the Delta Wing concept.

Amazing the responses you get when you supply absolutely NO INFORMATION AT ALL.

[Fat Boy]

I suppose the diff. worst case would be one wheel permanently locked (assuming that could happen).

Yep, one wheel locked and the other open. That's pretty much worst case, assuming you aren't also using the brakes for increased influence. It didn't seem to work out all that well for Tony Kanaan last year at the Speedway when it happened to him. That's worst case, but it's a case that could happen. Since it may be used as a primary means of turning the car, it would probably happen more often than axle failures.

[imaginesix]

In fact I don't believe I've heard so many frivolous, uninformed comments about motor racing in many years and it's sad to see many people who have no engineering or technical knowledge so easily dismiss the Delta Wing concept.

Amazing the responses you get when you supply absolutely NO INFORMATION AT ALL.

LOL! 10/10

[Greg Locock]

Here's my guess

Deltawing spec Units Source

Empty weight 850 lb SAE
Racing weight with 75kg driver+40 kg fuel 501.4 kg G
Weight dis %F 27.5 % SAE
Faxle 137.9 kg G
Raxle 363.5 kg G

A 0.8312 m^2 G track+.3 tire width *.4 high, also back calc from top speed
Cd 0.24 SAE
L/D 10.9 G based on venturi/body CL from F1
Cl 2.616 G calc

HP 325 hp 235
Top speed 378 kph SAE

Front track 610 mm SAE
Rear track 1778 mm SAE
Wheelbase 2735 mm Scaled from photo

J 245 kg m^2 G
Crr1 0.02 G
refs
222 http://gordonkirby.c...t_is_no222.html
235 http://www.gordonkir...t_is_no235.html
SAE http://www.sae.org/mags/aei/mtrsp/7658
G guess or calc

[dosco]

So I think it was the latest edition of Machine Design that had an article about the new Indycar concepts.

IIRC the article stated that a decision was to be announced at the end of May(?). What's the latest on the announcement of a decision?

[sblick]

So I think it was the latest edition of Machine Design that had an article about the new Indycar concepts.

IIRC the article stated that a decision was to be announced at the end of May(?). What's the latest on the announcement of a decision?

Since they just announced 500- 750 horse as their new engine that would preclude the Delta Wing so everone can untighten their panties

[Ross Stonefeld]

Not really, as the Delta Wing as more of a concept. I don't think they were locked into 300hp, just that they could achieve the targets they wanted with that level of power. If anything a Delta Wing, even running exactly as the design study, would be a beast with 550hp.

[sblick]

Not really, as the Delta Wing as more of a concept. I don't think they were locked into 300hp, just that they could achieve the targets they wanted with that level of power. If anything a Delta Wing, even running exactly as the design study, would be a beast with 550hp.

Ross I guess you would be right. It doesn't really nix it as an option but I think the writng is on the wall. I personally really like the ideas behind it and what it stands for. It is unfortunate that we may never see it run in anger or that a junior series couldn't give it a go.

[cheapracer]

It is unfortunate that we may never see it run in anger or that a junior series couldn't give it a go.

And if we never see it run who's fault is that?

Appears that the designers are after money in the way of it will only happen if someone else pays for it rather than marketing and backing up the concept to other arenas themselves.

[Greg Locock]

And if we never see it run who's fault is that?

Appears that the designers are after money in the way of it will only happen if someone else pays for it rather than marketing and backing up the concept to other arenas themselves.

I think they have raised some interesting points.

The high speed/low power approach doesn't seem likely to provide better racing, it may be more politically acceptable. It might be cheaper.

eliminating wheel interlocking seems like a good idea since the accidents that are caused by that are inherently unpredictable and 3 dimensional.

eliminating wings - i don't have an opinion. presumably aero will be adjusted via rake and ride height.

making it look like a jetfighter - initially yes it'll get some attention. I haven't noticed that any of the cartoon car series (the aussie midgets and so on) have really taken off. Since the entire field willl look identical I don't see it as being attention grabbing for committed spectators for long. But I could be wrong. Maybe since TV is the dominant audience something crazy looking will bring in more eyes.

restricting the front suspension design so that some form of rear steer is necessary- I don't see that 4WS has to be horribly unreliable, but agree with Fatboy that extra complexity in the driver's primary control seems to be asking for trouble. There again at high speed you'd mostly use front wheel steer (?) so perhaps it is not too bad.

"one design, many builders, one measuring company" - I think that is the weakest point in the whole concept.It transfers the development risk from the teams to the builders. I know racing teams aren't rich, by and large, are racecar builders? But yes, I would like to be the commercially rewarded measuring authority. Wot I sez goes. And I bet the ones I build are front runners.

As to whether any of the other proposals will attract audiences back again? I certainly don't know.

I think aesthetically there is a lot to be said for the F5000 look (I spent more time looking at them than watching the race) - you can understand the shapes, if they aren't graceful they are at least purposeful. Current F1 cars look like flamingos, OK, there is a purpose in every part, but the whole thing is like an IMS yacht, a series of disjointed design features that get around a set of arbitrary rules.

[saudoso]

Active diferential and vectored thrust are too things that just seem diametrally oposed to IRL. But what do I know.

And it seems the delta will ditch the road tracks AGAIN. IRL done that once to no avail.

Here a tiny bit illustrating why the narrow front track is such a dummy idea in my oppinion:



Please keep in mind that opinions are like arses, everyone has one and most them are pretty much as good.

I promisse I'll put the geometry togheter on how bad to handling and security it is tomorrow.

Edited by saudoso, 05 June 2010 - 03:13.

[gruntguru]

Active diferential and vector thrust are too things that just seem diametrally oposed to IRL. But what I know.

Here a tiny bit illustrating why the narrow front track is such a dummy idea in my opinion:

Has the active differential been confirmed or just a rumour started by Fat Boy?

Love the clip, but I think you will find the Reliant Robin has

1. Much narrower front track than Delta Wing.

2. Much higher CG than Delta Wing.

3. Much less rear weight (55%) than Delta Wing (72.5%).

Please keep in mind that opinions are like arses, everyone has one and most them are pretty much as good.

Of course you weren't referring to Mr Kirby's opinion. Or his arse. Or were you?

[saudoso]

Has the active differential been confirmed or just a rumour started by Fat Boy?

Love the clip, but I think you will find the Reliant Robin has

1. Much narrower front track than Delta Wing.

2. Much higher CG than Delta Wing.

3. Much less rear weight (55%) than Delta Wing (72.5%).

I know that much, this is the extreme case. But the almost 3 wheeler arrangement surely is no improvement on the square, 4 wheels one.

It's prone to problems and people will start asking the heavens what went wrong when it does. Think flying Le Mans and add "I did tell you before" to it.

Of course you weren't referring to Mr Kirby's opinion. Or his arse. Or were you?

Just my own, I could have been clearer. Some people really don't like we speak against this.

Edited by saudoso, 05 June 2010 - 11:53.

[Ross Stonefeld]

It's not about the opinions, but the level and quality of argument. Trying to equate the Delta Wing design, even in it's most literal interpretation, with Reliant Robins or flying Mercs at Le Mans ('55 or '99?) would appear comical even in the petri dish of Racing Comments.

[saudoso]

It's not about the opinions, but the level and quality of argument. Trying to equate the Delta Wing design, even in it's most literal interpretation, with Reliant Robins or flying Mercs at Le Mans ('55 or '99?) would appear comical even in the petri dish of Racing Comments.

I said once and will do agian.

I think the geometry is sub optimal and it won't work. The Reliant Robins is as joke, I know that. But such a car design will have problems braking and putting it's nose into turns.

It's not pure armachair expertise, I'm an engeneer and had my share of CG, moments of inertia and leverage.

I might be wrong, but that's what I think. Now about your argument, other than trying to descontruct what I say?

Edited by saudoso, 05 June 2010 - 12:20.

[saudoso]

I just found this (should have read it before, I know):

http://www.gordonkir...t_is_no222.html

It does goes against all I say, but here:

"The first question was, could it work? We did some simulation experiments and to our great suprise the vehicle dynamics were incredible. We thought we must be messed up here. But no, we weren't."


Well, I still think they were. The airplane example is great (and it also applies to salt cars): This setup is great for straight passes.

[Paolo]

Downforce will prevent Deltawing from overturning.

[gruntguru]

I just found this (should have read it before, I know):http://www.gordonkir...t_is_no222.html

It does goes against all I say, but here:
"The first question was, could it work? We did some simulation experiments and to our great suprise the vehicle dynamics were incredible. We thought we must be messed up here. But no, we weren't."
Well, I still think they were. The airplane example is great (and it also applies to salt cars): This setup is great for straight passes.

So you still think your gut feeling is closer to reality than Gordon Kirby, his team and their simulations?

Time to re-visit your quote about opinions and arse-holes.

Edited by gruntguru, 05 June 2010 - 23:08.

[MattPete]

Here a tiny bit illustrating why the narrow front track is such a dummy idea in my oppinion:

I, too, initially thought the same thing. An [essentially] 3-wheel car with one wheel in the front is stupid. It's like a 3-legged stool. Or the old 3-wheel ATVs that had so many problems with roll-overs (I experienced one myself the first time I got on one). After all, all of the successful 3-wheel designs had two wheels in front.

BUT, the Deltawing isn't like those other 3-wheelers (yes, I know the Deltawing has two wheels in front). It has a radical rear weight bias. Perhaps that allows it to handle more like a conventional 4-wheel car.

Having said that, I think the design was too goofy looking. A compromise, like one of the Swifts (e.g. #33), would be a better choice.

[REN_AF1]

I cant believe this.. Now they are hoping for a slot at the 2012 Le mans..
someone ought to give those guys a quick lesson on stability.

Imagine this; Fast right hander, inside rearwheel (which you cant see by the way) hit the curb hard and woopti, over you goes..Low CG and weight does not help you one bit, actually quite the opposite.
My 8 year old son could probably work out the math on that one, and so can they i am sure; its a scam somehow i just haven't found out how the cash flow is precisely..

R

[sblick]

I am very excited to watch one get built and raced. It will be nice to see Gurney and AAR bring the car to life and see how she goes. Whomever from Highcroft who drives this first will have a big set dangling. To me this is what racing is about. Try something out of the ordinary, take a wild shot. This is way out of the box thinking. If it wasn't for engineers or intelligent people thinking out of the box where would we be.

[REN_AF1]

I am very excited to watch one get built and raced. It will be nice to see Gurney and AAR bring the car to life and see how she goes. Whomever from Highcroft who drives this first will have a big set dangling. To me this is what racing is about. Try something out of the ordinary, take a wild shot. This is way out of the box thinking. If it wasn't for engineers or intelligent people thinking out of the box where would we be.

That is EXACTLY the problem.. This is not engineers thinking out of the box, This is Marketing thinking out of the box. And as always when this happens, Engineers suffer..

Try to do the wild shot/extra ordinary thing and remove the transmission of your car to save weight, i will pretty much guarantee you that you will not win any race that day..
Making a racecar handling bad to improve racing, WTF.. A Joke through and through.

Luckily this abomination will never see the light of day

R

[Ross Stonefeld]

No Buck, no Buck Rogers. You want to engineer? Make friends in marketing.

[REN_AF1]

No Buck, no Buck Rogers. You want to engineer? Make friends in marketing.

A bit exaggerated perhaps, but there are two ways to do business;
Sell what you want to make, or make what you want to sell.. Luckily my occupation lies is in the first category, but that does not mean that i never had to tell the marketing guys that a particular wish from them was daft from a technical standpoint.
The point is, that someone should have done so here, to..

R

[Ross Stonefeld]

Why? What is fundamentally wrong with the car?

Everyone moans that there's no diversity in racing, the rules are too restrictive, pick the cliche of the day. Then when someone goes out and does something different, everyone closes ranks and crucifies them. Don't make the DeltaWing. Don't make an all CFD car. Don't make a Walrus nose.

[cheapracer]

Why? What is fundamentally wrong with the car?

Impossible to comment until it turns a wheel of course, I think Reliant Robin is deeply imbedded in peoples brains when they think of a 3 wheel layout (yes I know it has 4).

I would be concerned for the rear wheels "sticking out", needing a driver to constantly be aware of it and that's easier said than done I think especially when "diving up the inside"...

Also I still see a lot of frontal area that 300hp has to still push, I don't think it will be as fast as they believe - that reminds me of the Tyrell P34 6 wheeler when they kind of forgot about the big rear wheels

[REN_AF1]

Impossible to comment until it turns a wheel of course, I think Reliant Robin is deeply imbedded in peoples brains when they think of a 3 wheel layout (yes I know it has 4).

I would be concerned for the rear wheels "sticking out", needing a driver to constantly be aware of it and that's easier said than done I think especially when "diving up the inside"...

Also I still see a lot of frontal area that 300hp has to still push, I don't think it will be as fast as they believe - that reminds me of the Tyrell P34 6 wheeler when they kind of forgot about the big rear wheels

The Tyrell P34 was not an effort to reduce frontal area.
The idea where to get better front end grip and better braking, and as such it where an excellent idea, pushing the rules to the limit.. Not stupid and overlooking obvious "terminal" flaws, like the delta..

And the flaw with the delta is off course the inherent lack of stability in a three wheel configuration, and as stipulated, it is impossible to quantify without knowledge of the exact CG of the contraption.
One can however with certainty say that it is a lot less stable than a four wheel car with same CG.

To be honest i think they made a screwy loadset in their simulation and simply forgot to include excitations of any sort (if they didn´t just use the rFactor mod as "simulation" :-)

R

Edited by REN_AF1, 11 June 2011 - 17:02.

[Ali_G]

The Tyrell P34 was not an effort to reduce frontal area.
The idea where to get better front end grip and better braking, and as such it where an excellent idea, pushing the rules to the limit.. Not stupid and overlooking obvious "terminal" flaws, like the delta..

And the flaw with the delta is off course the inherent lack of stability in a three wheel configuration, and as stipulated, it is impossible to quantify without knowledge of the exact CG of the contraption.
One can however with certainty say that it is a lot less stable than a four wheel car with same CG.

To be honest i think they made a screwy loadset in their simulation and simply forgot to include excitations of any sort (if they didn´t just use the rFactor mod as "simulation" :-)

R

I can't imagine that the front will be too stable under braking. What will it be like when turning in under braking.

[Ross Stonefeld]

The Tyrell P34 was not an effort to reduce frontal area.
The idea where to get better front end grip and better braking, and as such it where an excellent idea, pushing the rules to the limit.. Not stupid and overlooking obvious "terminal" flaws, like the delta..

And the flaw with the delta is off course the inherent lack of stability in a three wheel configuration, and as stipulated, it is impossible to quantify without knowledge of the exact CG of the contraption.
One can however with certainty say that it is a lot less stable than a four wheel car with same CG.

To be honest i think they made a screwy loadset in their simulation and simply forgot to include excitations of any sort (if they didn´t just use the rFactor mod as "simulation" :-)

R

It has four tires.

[REN_AF1]

It has four tires.

So to had the Farmall B Narrow front, it also had the CG Waay back + active braking.. Heyy let´s race the fücker.. Now THATS out of the box thinking..

R

Edited by REN_AF1, 11 June 2011 - 18:15.

[Ross Stonefeld]

Well if you're going to claim the flaw in the DeltaWing is the amount of tires, make sure you count them correctly.

[REN_AF1]

Well if you're going to claim the flaw in the DeltaWing is the amount of tires, make sure you count them correctly.

Are you stringing me on :-)
I did actually say; three wheel "configuration". It´s a subtle difference i know, but its there.

Edit: Ahh now i see your point.. I meant off course compared to a conventional four wheel car, where said wheels are located along a diagonal pattern, in or near the vicinity of outermost corners of same device.
Sorry

R

Edited by REN_AF1, 11 June 2011 - 18:24.

[cheapracer]

I can't imagine that the front will be too stable under braking. What will it be like when turning in under braking.

Why not? All the braking forces are kept near the car's centerline.

I would imagine they will go for a spool drive as de-weighting the inside rear isn't going to be difficult, that spool will also help braking stability.

[Slowinfastout]

Do they have a usable Deltawing prototype yet?

I have the impression I'm supposed to endorse this thing before I actually see it run a couple of laps.. just build one already!

[cheapracer]

I have the impression I'm supposed to endorse this thing before I actually see it

Then their marketing is working!

[gruntguru]

I would imagine they will go for a spool drive as de-weighting the inside rear isn't going to be difficult, that spool will also help braking stability.

IMO that's the last thing they would do. The rear roll couple has to supply 90% of the roll resistance therefore the CG has to be waaaay back. It would be insane to run the CG high enough to unload the (only) inside tyre - that puts you squarely in Robin territory. Consequently the inside rear will always have a decent proportion of weight and you would never get the thing to turn in if you ran a spool.

Active torque split would be ideal but since its a race car hmmm. Did I hear someone say it will have active brake distribution across the rear? If so, run an open diff and use the active braking system to control torque distribution ah la electronic fiddle brake.