RE: Nissan powers DeltaWing Le Mans bid

[CBR JGWRR]

Back to the DeltaWing now.

[zebedee]

Matt p said:

CBR JGWRR said:

They weren't "banned". What happened was the regulations changed to make rotary powered cars not viable to run. An effective ban.

Still the only Japanese manufacturer to win Le Mans outright.

It was underhanded how the governing body went about it. Real shame really as if they had continued racing I'm sure they would of won a hell of a lot more.

Hey ho I'm content in owning my rx7

I have a feeling that the 787B was effectively racing under a special dispensation anyway the year it won, which no-one was too fussed about because they never thought it would be a contender. Wonderful car though.

[RenesisEvo]

doogz said:

Writing they were banned is completely different, not easier.

I'm genuinely interested, where they banned, or not?

It's hard to say, but it was interesting to see the engine rules a few years ago suddenly include rotary engines again. But nothing came of it - I was hoping Mazda might make a come back. But the Dyson Mazda-Lolas never strayed from the ALMS.

The 787B wasn't especially quick compared to its rivals, but it was the quickest thing left in '91 that lasted the distance. So there's no gurantee that it could have repeated that performance - how many other races did it win? None. So it being banned seems more of a political move than necessarily preventing a good engine dominating, but we'll never know.

Secondly, I agree that the DeltaWing is good for drawing attention to efficiency and reducing the fuel used, etc. But there's no reason a 'normal' prototype couldn't be built at ~500kg and run a small engine in the same manner. Most of the current prototypes are heavily ballasted anyway, given how many started life at the old 675kg limit for what was LMP675, now LMP2. Forcing up the weight (to reduce costs, apparently) doesn't seem very efficient to me.

[mig25_foxbat2003]

I think the FIA should insist that they produce at least 100 roadgoing versions. And then refuse to allow them to pull out of the race, on pain of pain. I'd LOVE to see one of these in Tesco's carpark.

[CBR JGWRR]

doogz said:

CBR JGWRR said:

Aside from the source issues...

Writing they were banned is easier.

Writing they were banned is completely different, not easier.

I'm genuinely interested, where they banned, or not?

Banned like the Brabham fan cars, and the Chapparal 2J "sucker" cars were. Technically no, in practice yes.

Although for different reasons to the Mazda - the Chapparal 2J was because they used fans to suck air out from underneath the car, providing downforce, blocked under appendix J (I think it's J) because they were construed as movable aerodynamic devices, which aren't allowed. They used a snow mobile engine to power the fan.


Brabham adapted the idea to run the fan off the gearbox, and use the air for engine cooling (They said) as it meant that less than 50% was used for aero purposes, which was allowed.

They agreed not to race it afterwards.


The reasoning behind not allowing it was if the fans failed, then the car would go off the track, and safety wasn't exactly good back then.

Mclaren's complaints in Can Am about how the 2J would dominate the series didn't help either...


It has been a while since I looked this up, so check up on it, but that was what my research uncovered for an A-level engineering report.

[CBR JGWRR]

RenesisEvo said:

doogz said:

Writing they were banned is completely different, not easier.

I'm genuinely interested, where they banned, or not?

It's hard to say, but it was interesting to see the engine rules a few years ago suddenly include rotary engines again. But nothing came of it - I was hoping Mazda might make a come back. But the Dyson Mazda-Lolas never strayed from the ALMS.

The 787B wasn't especially quick compared to its rivals, but it was the quickest thing left in '91 that lasted the distance. So there's no gurantee that it could have repeated that performance - how many other races did it win? None. So it being banned seems more of a political move than necessarily preventing a good engine dominating, but we'll never know.

Secondly, I agree that the DeltaWing is good for drawing attention to efficiency and reducing the fuel used, etc. But there's no reason a 'normal' prototype couldn't be built at ~500kg and run a small engine in the same manner. Most of the current prototypes are heavily ballasted anyway, given how many started life at the old 675kg limit for what was LMP675, now LMP2. Forcing up the weight (to reduce costs, apparently) doesn't seem very efficient to me.

Its a technicality really.

With Le Mans, the challenge isn't just being fast enough, it's about going the distance, at 90 plus percent, as a full on sprint for 24 hours.

[CBR JGWRR]

doogz said:

Thanks. I was aware of the "fan cars"

"It's only for cooling"

"Ok. Why does the car move closer to the ground when you rev it then?"

"Errrrrrmmmm..."

Yeah. A noticable side effect.

[Chris71]

mig25_foxbat2003 said:

I think the FIA should insist that they produce at least 100 roadgoing versions. And then refuse to allow them to pull out of the race, on pain of pain. I'd LOVE to see one of these in Tesco's carpark.

+1

It'd be even more extreme when you consider DeltaWing is based in the US. Over here you might get someone taking their Atom or R500 down to the shops, but can you imagine one of those parked next to all the F350s and Explorers at the local Walmart? Actually, that said they're based in California, so it'd probably be wall-to-wall Priuses and Teslas. But still....

[KDIcarmad]

In 1967 this car ....





The OSI Silver Fox was intended to run at Le Mans under group F rules (I may be wrong please correct me if I am) power comes from a 1000cc Alpine race engine. It never race, as it was incorrectly taken as an asset of the company readying it to race when they went out of business. It was only return after a legal battle and missing it race engine.

Le Mans has as always had odd and different cars entered. Personal I love the look of this one. Its design is very aerodynamic, and uses air breaks. Unlike the Deltawing it did fit the race rules. Could a update of this still be entered? It would be fun! Costly, but fun...! Do any of you have a millionaire friend up for a bit of fun!

[zebedee]

RenesisEvo said:

It's hard to say, but it was interesting to see the engine rules a few years ago suddenly include rotary engines again. But nothing came of it - I was hoping Mazda might make a come back. But the Dyson Mazda-Lolas never strayed from the ALMS.

The 787B wasn't especially quick compared to its rivals, but it was the quickest thing left in '91 that lasted the distance. So there's no gurantee that it could have repeated that performance - how many other races did it win? None. So it being banned seems more of a political move than necessarily preventing a good engine dominating, but we'll never know.

Secondly, I agree that the DeltaWing is good for drawing attention to efficiency and reducing the fuel used, etc. But there's no reason a 'normal' prototype couldn't be built at ~500kg and run a small engine in the same manner. Most of the current prototypes are heavily ballasted anyway, given how many started life at the old 675kg limit for what was LMP675, now LMP2. Forcing up the weight (to reduce costs, apparently) doesn't seem very efficient to me.

Are you saying any of the current P2 chassis in WEC/Le Mans are from the 675 era? If so, which ones? The problem with 675 was the cars were just so fragile and wouldn't go the distance, so if you wanted to keep the weight down and reliability up, it cost an absolute fortune. There is no market for that in P2 racing these days.

[robmlufc]

zebedee said:

Are you saying any of the current P2 chassis in WEC/Le Mans are from the 675 era? If so, which ones? The problem with 675 was the cars were just so fragile and wouldn't go the distance, so if you wanted to keep the weight down and reliability up, it cost an absolute fortune. There is no market for that in P2 racing these days.

I'm not sure about the current ones but there was an MG675 running around in LMP2 disguise last year.

[zebedee]

robmlufc said:

I'm not sure about the current ones but there was an MG675 running around in LMP2 disguise last year.

RLR's (ex RML)? That was a much revised development of the 675 car and would have been beefed up in some pretty significant areas over the years I would have thought, enough to constitute a significant departure from the 675 ethos.

[NickyTwoHats]

BarnatosGhost said:

Interesting post. I can see the 'point' in a shape like concorde, for displaying as much of the frontal area in wing format as possible,

I think the point of for displaying as much of the frontal area in wing format as possible is that UPSIDE DOWN wings give downforce

[RenesisEvo]

zebedee said:

Are you saying any of the current P2 chassis in WEC/Le Mans are from the 675 era? If so, which ones? The problem with 675 was the cars were just so fragile and wouldn't go the distance, so if you wanted to keep the weight down and reliability up, it cost an absolute fortune. There is no market for that in P2 racing these days.

In terms of the actual tubs it's hard to be sure. For example, the Acuras and Lolas have all slowly evolved from those days - the current Lola has clear links to the MG-badged prototype from a decade ago. The Acura tubs last year were pretty much the same Courage tubs that were from the C65 of 2003 vintage. Only for this year has Wirth Research updated the tub. The evolution has been slow and limited, mostly driven by rule changes, some of which have increased costs by forcing regular changes.

I agree that things have changed, and the more robust, heavier cars are better. The DeltaWing risks having the fragility you mention because of its lightweight approach. But my point is, the DeltaWing is seemingly claiming that low weight, low power, more efficiency is a new, exciting concept for motorsport. But it really isn't - efficiency has long been the top priority in F1 and other motorsports. I say this from being/having been involved in F1 and competitive LMP cars.

[zebedee]

RenesisEvo said:

zebedee said:

Are you saying any of the current P2 chassis in WEC/Le Mans are from the 675 era? If so, which ones? The problem with 675 was the cars were just so fragile and wouldn't go the distance, so if you wanted to keep the weight down and reliability up, it cost an absolute fortune. There is no market for that in P2 racing these days.

In terms of the actual tubs it's hard to be sure. For example, the Acuras and Lolas have all slowly evolved from those days - the current Lola has clear links to the MG-badged prototype from a decade ago. The Acura tubs last year were pretty much the same Courage tubs that were from the C65 of 2003 vintage. Only for this year has Wirth Research updated the tub. The evolution has been slow and limited, mostly driven by rule changes, some of which have increased costs by forcing regular changes.

I agree that things have changed, and the more robust, heavier cars are better. The DeltaWing risks having the fragility you mention because of its lightweight approach. But my point is, the DeltaWing is seemingly claiming that low weight, low power, more efficiency is a new, exciting concept for motorsport. But it really isn't - efficiency has long been the top priority in F1 and other motorsports. I say this from being/having been involved in F1 and competitive LMP cars.

It does risk it, but it has less car anyway, so what it does have doesn't have to be made to the lightest tolerances possible, plus the lack of initial weight means further weight savings elsewhere like suspension components, brakes etc, in theory anyway.

As to the frontal area argument, it isn't very wedge shaped and after the nose pierces the air, it looks like it is then managed under the car and around the cockpit area, so when the second 'front' hits, it does look like it has a lot less impact than the front of a typical car. It is odd watching the onboard camera though, poor Marino has to deliberately 'miss' every apex with the front of his car, must be very hard to get your head around!

[RenesisEvo]

zebedee said:

stuff

Couldn't agree more, it must take some getting used to for the driver. I think the double-headlamp set-up could be useful, especially if you point the nose-mounted ones at the opposite kerb, and the rear ones straight ahead.

[TransverseTight]

Here's an idea - about understeering - who says the front does the steering, maybe the wheels at the front are just there to stop the nose scraping the tarmac. As someone else has posted - think Segway. You can push or drag the rear wheels at different speeds to get turning force. This car is so far out the ordinary it wouldn't suprise me to find they are using some kind of active torque split across the rear wheels.

Likewise - look how long the car is - think lever. A little bit of force at the front can pull a lot of weight at the other end of the chassis into a corner. I.e think about how little force is required on a long handled torque wrench to get the hard bit (the nut) to turn.

Lastly - if there's no weight at the front of the car - (isn't ii almost 80/20 rear to front weight split?). So a massive difference compared to conventional cars. I don't know the relationship between grip and weight when the numbers change so much, but it probably isn't linear - especially given its not just the percentage difference, it will also depend on where the CoG is in relation to that distribution. Its probably just in front of the rear wheels - not half way between them. So you may find you can get away with a 85% skinnier tyre when you shift the weight distribution back 30%. Some maths guru can chip in here with some simultaneous equations.

Si
(1st post on PH ... been lurking for ages. Off to Le Mans again this year and this car has me so excited I couldn't keep quiet, LOL!).

[zebedee]

TransverseTight said:

Here's an idea - about understeering - who says the front does the steering, maybe the wheels at the front are just there to stop the nose scraping the tarmac. As someone else has posted - think Segway. You can push or drag the rear wheels at different speeds to get turning force. This car is so far out the ordinary it wouldn't suprise me to find they are using some kind of active torque split across the rear wheels.

Likewise - look how long the car is - think lever. A little bit of force at the front can pull a lot of weight at the other end of the chassis into a corner. I.e think about how little force is required on a long handled torque wrench to get the hard bit (the nut) to turn.

Lastly - if there's no weight at the front of the car - (isn't ii almost 80/20 rear to front weight split?). So a massive difference compared to conventional cars. I don't know the relationship between grip and weight when the numbers change so much, but it probably isn't linear - especially given its not just the percentage difference, it will also depend on where the CoG is in relation to that distribution. Its probably just in front of the rear wheels - not half way between them. So you may find you can get away with a 85% skinnier tyre when you shift the weight distribution back 30%. Some maths guru can chip in here with some simultaneous equations.

Si
(1st post on PH ... been lurking for ages. Off to Le Mans again this year and this car has me so excited I couldn't keep quiet, LOL!).

The front wheels do turn, you can see it happening on the in-car/on-car shots

[M@1975]

Awesome Batman FTW!

[BarnatosGhost]

NickyTwoHats said:

BarnatosGhost said:

Interesting post. I can see the 'point' in a shape like concorde, for displaying as much of the frontal area in wing format as possible,

I think the point of for displaying as much of the frontal area in wing format as possible is that UPSIDE DOWN wings give downforce

Yes, but the shape hasn't got lovely wings, upside down or otherwise, at the lateral extremities. It's got horrid draggy wheels.