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#1 f1steveuk

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Posted 10 August 2014 - 12:03

I had a and interesting conversation yesterday with someone I consider to be one of THE unsung heroes of motorsport. I have always listened to what he has had to say, and he has never been anything other than accurate and informed, so I have taken the things he has told me as being, more or less, Gospel!

 

Yesterday, in answer to a question about "what ifs", he said, " yep, like the Lotus 88, most felt it was Colin having a go at authority, showing them up for making awful regulation decisions, but had it raced, it would have been bloody fantastic".

 

Really!!?? I have to say I was leaning more toward the prior, a bit like the 76, if it had worked, great, but a bit of an experiment. So this statement intrigued me. I have never seen a qoute from anyone within Lotus at that time regarding wind tunnel figures, and it's testing performance was less than impressive, but my "chum" was adamant. Sadly we ran out of time, but I will tackle him on this again as soon as I get the chance, but am I right, or have I missed something?


Edited by f1steveuk, 10 August 2014 - 14:43.


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#2 Michael Ferner

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Posted 10 August 2014 - 12:29

In theory, the concept should have worked magic, but as you I doubt it could have been made into a workable car. In any case, the hydraulics worked much better, much cheaper and more within the rules, so it's a philosophical question.

#3 Tim Murray

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Posted 10 August 2014 - 12:31

I've always believed that the basic engineering concept was sound, and if they could have sorted the teething problems before it was banned it would have been very competitive. It solved the problems introduced by the 1981 regs in a much more elegant fashion than the Brabham jacking suspension which everyone else then copied, and gave the driver a much softer ride. Check out this discussion of the car in the Technical Forum:

http://forums.autosp...06859-lotus-88/

#4 arttidesco

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Posted 10 August 2014 - 13:21

I always understood the basic problem with the 88 was that Bernie and his boys were frightened that the 88 would render everything else obsolete, reliability not withstanding, as had the 78 and 79, I could of course be mistaken by my specs being tinted with just a hint of cynicism. Let us not forget the 88 only came about after the unraced 86 had been cured of it's oil leaks and tested the basic principles,  behind the 88, to Mr Chapman's satisfaction.



#5 f1steveuk

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Posted 10 August 2014 - 14:47

As the 86 begat the 88, the 77 was really only a test bed for what was to become the 78, less the aero' of course! So it was a route Lotus had taken before. I could see the 86/88 principle working brilliantly at Indy, constant speed etc, but Monaco?



#6 kayemod

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Posted 10 August 2014 - 17:45

The 88 divided opinion within Lotus, I'd left  years before but still had one or two contacts. One told me that some thought that "The Old Man knows what he's doing" and believed in the car, ignoring the lessons a few well known past failures, and others didn't see how it could possibly work, but probably kept their opinions to themselves. With the benefit of almost 30 years hindsight, I'm still a doubter, but surely it wasn't all that impressive in testing and its brief career? The 80 was a failure from the start, but it was a while before Chapman bowed to the inevitable and scrapped it. Still a near-genius in my opinion, but ACBC did have his off-days.



#7 Nemo1965

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Posted 10 August 2014 - 18:40

As the 86 begat the 88, the 77 was really only a test bed for what was to become the 78, less the aero' of course! So it was a route Lotus had taken before. I could see the 86/88 principle working brilliantly at Indy, constant speed etc, but Monaco?

 

Well, I am not an engineer and Kayemod and other posters who either worked at Lotus or worked in F1 can better answer this question... but my thought would be that IF the 88 would work, the rub would be that it would work just as fine on slow tracks as on fast tracks. As I understand it, groundeffect cars have to have very stiff springs to keep the rideheight - and thus the position of the skirts - as constant as possible. Yes, the skirts slide up and down in the housing, but a groundeffect-car with soft springs is like a light-switch that can be moved by the wind... You want to minimise variance of ride-height to a minimum, because you don't want to screw up the venturi-effect of the aero-channels.

 

The Lotus 88 because it outer housing was in fact one giant 'skirt', could have used any spring settings in the 'inner chassis' that was deemed fit for any track, and mechanical grip did not have to be sacrificed for the ground-effect on the fast parts of the track. The chassis with the aero-channels (on both sides of the cars) move up and down with the wind, while the chassis with the mechanic parts as springs, move up and down with the shifting weight of braking and acclerating and the bumps in the road.

 

I could be wrong...



#8 2F-001

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Posted 10 August 2014 - 19:02

Following on from Tim's points (and Nemo's too) it also overcame the 'problems' created by the Monaco '69 rule-change (which set the pattern for every winged, stiffly-sprung racing car since) by putting the downforce back where it belonged - on the unsprung parts (the uprights) instead of applying through the springs which then have to have very high rates.

Given time for development, I've always thought it could have been very good. Sure, it didn't shine on its few brief runs, but presumably there were previously unknown problems of installation and 'packaging' and who knows what other new car issues it may have had - but is there a fundamental reason it couldn't have worked?

As for it only being really effective at constant speeds such as on ovals, as Nemo asks, why? Yes, venturi-induced down force is speed dependent, but surely the principle of the 88 is at least as good as any regular 'ground effects' car and possibly better: the downforce is applied directly where it's needed, the driver and drivetrain get an easier ride and there is more scope to tune mechanical grip too, freed from the necessity of huge spring rates.

One of my favourite cars, to be honest (up there with 2E, 2F etc…).

#9 Nemo1965

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Posted 10 August 2014 - 19:09

One of my favourite cars, to be honest (up there with 2E, 2F etc…).

 

Dito. Sigh...

 

240_jdjd.jpg



#10 2F-001

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Posted 10 August 2014 - 19:16

I've heard it suggested that Colin Chapman's enthusiasm to fight the 88's case was further blunted by the thought that the emerging unity and strength of the constructors was too important to long-term prosperity to risk jeopardising for a possible shorter-term technical advantage.
Does anyone have thoughts on that?

#11 ensign14

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Posted 10 August 2014 - 19:55

At the time, Lotus had financial difficulties, David Thieme was running out of money, the DeLorean was just starting its ill-fated production and Chapman was working on boats and planes as well.  I think the fight over the 88 was a scrap too far, especially as both FISA and FOCA were stitching him up over it, and its legality depended on a certain interpretation of the rules.  He could fight one, but not two.



#12 Doug Nye

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Posted 10 August 2014 - 20:04

I'd go along with that...

 

DCN



#13 kayemod

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Posted 10 August 2014 - 21:59

At the time, Lotus had financial difficulties...

 

There was never a time when they didn't, and that affected an awful lot of what they did. I don't think that Lotus was ever really profitable during Chapman's time, though in later years sponsors paid for the racing, hence the relevance of the shaky Essex funding. Somewhat OT, but Financial director Fred Bushell was the man who kept the company proper more or less afloat for many years, he was guilty as charged over the DeLorean mess, but it was sad that Chapman's loyal lieutenant was the only one to be banged up for it. Fred could have written one hell of a book had he been so inclined, because I don't think that the full story has ever been revealed.

 

On the general point Ensign made, my impression is that the whole thing was just getting too much for Chapman, he had more going on than he was able to handle, it was all coming at him from all sides.



#14 Henri Greuter

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Posted 11 August 2014 - 07:20

I must look it up but exactly where it was written down but I remember that Heinz Prüller wrote in his Grand prix story '81 a comment that one of the lotus drivers that year was oredered to tell that the 88 was fantastic but that the truth was that the car scared the hell out of him and was difficult to drive.

 

Henri

 

Edit: I must add to this that I think that had the time, money and efforts to sort it out properly been available, it may have been interesting to see.

Other inventions that initially didn't work at all have become a mjor succes second time out or after an development process. Think about the 1986 Brabham that `donated its principles to the 1988 mcLaren. or, Even within Lotus themselves: Active Suspension.

 

Henri


Edited by Henri Greuter, 11 August 2014 - 07:41.


#15 f1steveuk

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Posted 11 August 2014 - 09:30

I cannot recall the air speed needed to get the outer body down against it's stops, but I do recall Chapman on the TV showing the principle by kneeling on the body to push it down, and, although reasonably easy, it did require a bit of effort, so my comment regarding Monaco was directed at the very slow corners, where the outer body may well have popped up, but then again, those are the corners your less likely to require full on ground effect! It was suggested to me there may have been a lock down mechanism to prevent this, but that would be for someone on the inside to confirm. I have seen drawings, produced by another team that had a similar concept, in which the monocoque and side pods were "normal, and the entire upper bodywork, side pod tops and sides, were one big moulding, mounted down on to soft springs, that in essence did the same as the 86/88, in that forward speed pushed the entire top down, so the sides rubbed the ground. The reason given to me for the reason to stop development was the sheer wieght of the one piece body, then weeks later out comes the 86! My friend worked on this earlier version, obviously for a different team,and it was the figures generated as a wind tunnel model, that makes him feel the 86/88 WOULD have worked. As he said, "when we saw what Colin had done, it did what we were thinking, but better, and much lighter. We just looked and thought, bugger, so we started work again, only for the jumped up reason to ban it".  Those last nine words said a lot to me.

 

Of course, wind tunnel theory, and on track practise don't always mean the same thing.....................................


Edited by f1steveuk, 11 August 2014 - 11:43.


#16 Michael Ferner

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Posted 11 August 2014 - 10:13

I'm not sure I understand the part about the "jumped up reason", but the Lotus 86/88 was illegal if ever a car was! The bullshit about primary and secondary chassis was just smoke screen; there was just one chassis, and (illegal) moveable areodynamic devices fitted (illegally) to the unsprung parts of the car. If Chapman really thought he could get away with this, then he was a few screws short of a hardware store - which I don't think he was, not for a minute. So, what was it REALLY all about?

#17 f1steveuk

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Posted 11 August 2014 - 11:02

As I said in the original post, some thought it was ACBC having a dig at the rule makers. Bloody expensive way of making a point though!



#18 kayemod

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Posted 11 August 2014 - 11:30

As I said in the original post, some thought it was ACBC having a dig at the rule makers. Bloody expensive way of making a point though!

 

Not all that expensive, the 88 was based on the 87, and reportedly it only took something like 12 hours work to convert an illegal 88 into a legal 87. I still think that if Chapman's "twin chassis" idea had real merit, then the car would have shown a lot better in testing and the small amount of running it managed at GPs. Other ground-breaking cars have impressed right out of the box, but the Lotus 88 never did.



#19 PeterElleray

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Posted 11 August 2014 - 11:34

I've been reading this thread with interest, and i have to admit that the 88 has always puzzled me, on many different levels.

 

I think i am right in saying that the original concept was designed with sliding skirts in mind, and then rejigged with vestigial fixed skirts before the car first ran, after the resolution of the 1980/81 fisa/foca wars..

 

As a fixed skirt machine the only way i could see it working was if the secondary - or was it primary - chassis , anyway, the sprung bodywork, was softly sprung and effectively just sat on the track by the time the car reached the end of the pitlane and stayed there.

 

In other words the opposite of what some press reports of the time were claiming as quotes from Lotus personnel - smoke and mirrors or the press getting the wrong end of the stick?

 

That being the case the aerodynamic centre of pressure - and hence aero balance - would have been pretty much fixed through the 'flight envelope' of the car, unless there was significant separation in the tunnels, which i am assuming there was not.

 

But the conventional car underneath would still have been transferring weight backwards and forwards as it braked and accelerated.

 

These days you design a tunnel car to have an aerodynamic centre of pressure that moves in sympathy with this transfer so that, for instance as you brake and throw weight forwards you also move the aero forwards .

 

One of the secrets to having a car that the drivers think is well balanced is how much of this you build in and at what point you limit the shift in aero.

 

Too much and the car will be 'on the nose', too little and it 'wont have any downforce'. What they mean is it wont have the downforce where they can make use of it.

 

But the 88 wouldn't have had any of that, so i'm not too sure how it would have felt to deAngelis and Mansell and others who drove it out on the limit.  The car has been raced in Historics in recent years so maybe somebody from there can add some insight?

 

Anyway, it does make me wonder if the concept isn't actually fundamentally flawed - perhaps unless you add in active ride?  We know that was coming, it was later painted as the 'answer' to the banning of the 88 concept, i wonder if it wasn't perhaps another part of the same package?

 

On a different note, the party line at the time was that the 87 was designed as a failsafe in case the 88 didnt work, whereas i have it on fairly good authority that the 87 came first (as you might expect from its type number) and that the 88 was then given the go ahead after the 86 test car was felt to be showing some promise.

 

A lot more to this story than meets the eye...

 

Peter



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#20 f1steveuk

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Posted 11 August 2014 - 11:46

My list of questions just got longer Peter!!



#21 kayemod

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Posted 11 August 2014 - 12:07


On a different note, the party line at the time was that the 87 was designed as a failsafe in case the 88 didnt work, whereas i have it on fairly good authority that the 87 came first (as you might expect from its type number) and that the 88 was then given the go ahead after the 86 test car was felt to be showing some promise.

 

A lot more to this story than meets the eye...

 

Peter

 

Only hearsay, but my information was that the 87 & 88 design and build progressed in parallel from the outset, hence the ease of conversion from one to the other, but I'm sure that Peter gets it right with his final comment.



#22 PeterElleray

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Posted 11 August 2014 - 12:42

Quite possible that they did.

 

I think the way it was explained to me was that nothing on the 88 was designed in such a way as  to preclude a conventional car being produced from the same 'kit of bits' -  in which case they would have had to run in parallel, at least as far as design was concerned.

 

Either that tells us quite a lot about how confident Chapman was that the 88 would or would not be accepted, or it tells us how smart the team around him were in second guessing the outcome and planning ahead without the boss necessarily having the full picture! 

 

I think -but am not sure - that there may have been two or even three strands progressing in parallel - carbon chassis / sprung bodywork / and maybe early studies on active.

 

Out of those came the types 87,87B, 88,88B, 91,and 92. There is a very strong argument for describing all those cars as being of the same generic type, built around common tubs. (As were the 94 Renaults!)

 

It would probably have been more accurate if i had said that the 87 wasn't an afterthought, in other words the conventional car was in the pot from the start.

 

It seems clear that not too much of the 87 kit existed at the time the first 88 ran, because Lotus missed one race (Imola) and ran 81's at a second (Zolder, where Mansell was 3rd in one) before two 87's appeared at Monaco.

 

Those cars were built around different chassis to the 88 that was practiced in Brazil and Long Beach.

 

Chassis intended as 88's had the cutouts for the sprung body ladder framework, later 87's didn't. From memory those cars , or maybe one of them, did have the 88 cutouts in the tub. I have all this documented somewhere and can add or correct to that later if interested.

 

When the infamous mass conversion from 88's back to 87's took place overnight at Silverstone between practice days for the GP in July i think the logistics were influenced to some degree by this.

 

I have never really thought of the 87 and 88 as different cars.

 

Peter



#23 Nemo1965

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Posted 11 August 2014 - 12:47

Regarding the remark of Henry: I thought also that one of the Lotus drivers confided, later, that the 88 was rather dangerous and unpredictable. I already looked it up in GP Story 1981, but I can't find it in there. My guess it was either mentioned in an interview with Elio de Angelis in 1983 in GPI, or in an interview with Nigel Mansell.

 

Kaymod, I always had the impression that Chapman sort of felt more 'distant' from the F1 fraternity after especially the FOCA/FISA-war in 1980. I know he had his minds of other things outside F1, more than ever perhaps, (the whole De Lorean-saga, for example). I also remember some vague rumblings from Ken Tyrrel or some other old hand in F1 that stated that Essex's David Thieme was leading Chapman away from his roots into the world of showbusiness, or comments of that effect...

 

I am not saying that he build the 88 as a kind of archersfingers to the F1-fraternity, but in the case of the 88 there really seems to be some defiance on Chapmans side that I can't remember having read about earlier in his career...



#24 PeterElleray

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Posted 11 August 2014 - 13:21

 I thought also that one of the Lotus drivers confided, later, that the 88 was rather dangerous and unpredictable.

 

We're in 126C2 territory here...

 

Can we just settle for 'unpredictable' until we can find a decent, substantiated quote.

 

Unpredictable i can live with... If its 'dangerous' somebody better pull that 88B out of historics.

 

Peter



#25 f1steveuk

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Posted 11 August 2014 - 13:29

So, if the 86 begat the 88, what were the differences? And if the 88 was "heavily" based on the 86, why the 87 (if you understand my drift!?).

 

As hard as I try, I cannot reconcile how, once the aero chassis was down, and pressing the wheels down with it, that simple suspension movement might have broken the sealing strip from the track surface, defeating the object. I mean, surely, the aero chassis would have had to be down without any give against the suspenion arms, so if they were deflected upward, the aero chassis would lift.



#26 Charlieman

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Posted 11 August 2014 - 13:31

Not all that expensive, the 88 was based on the 87, and reportedly it only took something like 12 hours work to convert an illegal 88 into a legal 87.

Err that's 12 hours of mechanic time. We have to assume that Lotus designed and fabricated one and a half F1 models that winter. If you add in the opportunity cost (eg testing a car that never raced) when the grid was strong, that's expensive.



#27 Charlieman

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Posted 11 August 2014 - 13:45

As hard as I try, I cannot reconcile how, once the aero chassis was down, and pressing the wheels down with it, that simple suspension movement might have broken the sealing strip from the track surface, defeating the object. I mean, surely, the aero chassis would have had to be down without any give against the suspenion arms, so if they were deflected upward, the aero chassis would lift.

I follow your argument, Steve. If you apply similar logic to sliding skirts or active suspension, riding the kerbs reduced downforce but that driving technique worked. Some things just work when they shouldn't. Presumably there would have been some bumps and kerbs to avoid in a Lotus 88.



#28 PeterElleray

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Posted 11 August 2014 - 13:55

So, if the 86 begat the 88, what were the differences? And if the 88 was "heavily" based on the 86, why the 87 (if you understand my drift!?).

 

As hard as I try, I cannot reconcile how, once the aero chassis was down, and pressing the wheels down with it, that simple suspension movement might have broken the sealing strip from the track surface, defeating the object. I mean, surely, the aero chassis would have had to be down without any give against the suspenion arms, so if they were deflected upward, the aero chassis would lift.

The 86 was built around a 79/80/81 era aluminium tub  - i'm not sure which one. The rest of the mechanical assembly was from that generation also. If you have a good look at an 87-91 generation car you will see that a lot of the smaller parts (pedals, some suspension parts etc) are machined rather than fabricated, and completely different, almost a step change in design.

 

The sprung chassis on the 86 is very similar in detail to that used on the 88 - as you might expect, and is almost identical in concept..

 

The sprung body was suspended at the front from the rocker arms on small pullrods with gas struts at the bottom of the rods connecting to the sides of the structure, and a third memeber traingulating it to the bottom of the upright - quite complicated and a compleeling reason to argue that this was not bodywork but a chassis in its own right... There was a similar system at the rear.

 

If the spring rate of the struts was sufficient to allow the lower edge of the body sides, which carried rubbing strips,  to contact with the ground then you have a seal.

 

In the interview that has survived with Chapman conducted for Anglia TV in the summer of 81 he pushes the body down easily  with his knee, nearly giving the whole game away!

 

If there is some travel left in the gas struts then the rockers could move up as a wheel moved into bump and take up that travel without lifting the body - if the download from the underbody was greater than the load transmitted through the pullrod

 

So within limits i think you could accommodate bumps or low kerbs - but then none of the ground effect cars of that era could really deal with them very effectively.

 

I'm not too sure how well the system would have coped with cresting a brow that fell away - like Paddock Hill bend.

 

As to why the 87 - see my post above.

 

Peter



#29 f1steveuk

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Posted 11 August 2014 - 14:02

Interesting, I am begining to see my friends point. His conviction as to how good it would have been remains the puzzle!

 

At 6:36 on this, is the "knee press" though it seems quite firm to me.

 



#30 Nemo1965

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Posted 11 August 2014 - 14:05

We're in 126C2 territory here...

 

Can we just settle for 'unpredictable' until we can find a decent, substantiated quote.

 

Unpredictable i can live with... If its 'dangerous' somebody better pull that 88B out of historics.

 

Peter

 

 

I was referring to Henri's comment about one of the Lotus-drivers not particularly fond of the 88, and I remember that 'dangerous' was one of the words that said driver used. I hope that someone else can come up with the goods. I am not being paid to post, so I won't make writing real, journalistic work... I already find it rather silly from myself that I've ploughed through two books for this thread! :rotfl:



#31 Charlieman

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Posted 11 August 2014 - 14:06

That being the case the aerodynamic centre of pressure - and hence aero balance - would have been pretty much fixed through the 'flight envelope' of the car, unless there was significant separation in the tunnels, which i am assuming there was not.

 

But the conventional car underneath would still have been transferring weight backwards and forwards as it braked and accelerated.

The conventional chassis load transfers would be modest relative to aerodynamic download (25% of weight compared to say 300% of steady aero). It might provide the feel or balance that you describe.



#32 Charlieman

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Posted 11 August 2014 - 14:22

I'm not sure I understand the part about the "jumped up reason", but the Lotus 86/88 was illegal if ever a car was! 

Lawyers were never seriously involved -- at least in public. Like the Brabham fan car, the Lotus 88 can be argued to meet the letter of the regulations, but not the spirit. The car was banned in order for F1 development to avoid a blind alley; instead, F1 development went down different blind alleys. Legality is best ignored because the technology is much more interesting.



#33 PeterElleray

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Posted 11 August 2014 - 14:27

The conventional chassis load transfers would be modest relative to aerodynamic download (25% of weight compared to say 300% of steady aero). It might provide the feel or balance that you describe.

Well, 3g braking would transfer around 225kg onto the front axle in one of those cars - say 100kg per side. If the car was making its own weight again in downforce then that's only about 20kg more  on each front wheel in aero load...

 

But that's not the whole picture. A car that doesn't transfer any aero forwards as it pitches down usually feels like it lacks front downforce under braking - that's the point i was making.

 

That would have been the  inherent characteristic with a fixed underbody but to what extent it would have created a problem i'm not in a position to say. Just thinking out loud really.



#34 PeterElleray

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Posted 11 August 2014 - 14:30

I was referring to Henri's comment about one of the Lotus-drivers not particularly fond of the 88, and I remember that 'dangerous' was one of the words that said driver used. I hope that someone else can come up with the goods. I am not being paid to post, so I won't make writing real, journalistic work... I already find it rather silly from myself that I've ploughed through two books for this thread! :rotfl:

So, opening an old wound, but on topic this time, more 'pub talk' then...



#35 PeterElleray

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Posted 11 August 2014 - 14:40

Interesting, I am begining to see my friends point. His conviction as to how good it would have been remains the puzzle!

 

At 6:36 on this, is the "knee press" though it seems quite firm to me.

 

 

  Steve - believe me, thats soft ! Almost fully down under less than a mans weight.



#36 Charlieman

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Posted 11 August 2014 - 14:59

But that's not the whole picture. A car that doesn't transfer any aero forwards as it pitches down usually feels like it lacks front downforce under braking - that's the point i was making.

One of your assumptions is that Chapman sought a static centre of pressure for the Lotus 88. The previous year's ground effects cars with sliding skirts did not have static centre of pressure. If the cars worked, centre of pressure moved (a smidgeon) backwards under acceleration and forwards under braking; when aero didn't work, the cars porpoised. 

 

I'd consider the problem to be about predictable centre of pressure rather than static. I'm thinking aloud too.



#37 f1steveuk

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Posted 11 August 2014 - 15:09

  Steve - believe me, thats soft ! Almost fully down under less than a mans weight.

Fair point Peter. I have to say, the more I try and get my head around the whole concept, like fixed aero, fore and aft pitching, as well as yaw, the more I can see it working. I'm trying to work out if I know anyone who has driven one in historic, assuming they are allowed to run with the aero chassis having full movement?



#38 PeterElleray

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Posted 11 August 2014 - 16:03

One of your assumptions is that Chapman sought a static centre of pressure for the Lotus 88. The previous year's ground effects cars with sliding skirts did not have static centre of pressure. If the cars worked, centre of pressure moved (a smidgeon) backwards under acceleration and forwards under braking; when aero didn't work, the cars porpoised. 

 

I'd consider the problem to be about predictable centre of pressure rather than static. I'm thinking aloud too.

No - my assumption is the opposite - that  the 88 would have had a static centre of pressure, not that this was necessarily what  Chapman (or more likely Peter Wright) wanted to achieve.

 

I'd be very interested to know the answer to that because I don't remember too much talk about controlling the CP back in those days. 

 

The early ground effect cars had a small CP migration because the effective curvature of the pod roof altered with   pitch angle, and the ratio of throat area to diffuser area changed along with changes in  ride height .

 

As you say it was small compared to what you get with a flat bottom car with diffuser

 

Your last sentence about a predictable CP migration is precisely the point i was making earlier when i talked about a controlled shift forwards under braking.

 

You have achieved the aim of making that shift predictable when the driver tells you that he can use all the downforce when turning in.

 

So, in other words - we agree!

 

Peter



#39 PeterElleray

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Posted 11 August 2014 - 16:06

Fair point Peter. I have to say, the more I try and get my head around the whole concept, like fixed aero, fore and aft pitching, as well as yaw, the more I can see it working. I'm trying to work out if I know anyone who has driven one in historic, assuming they are allowed to run with the aero chassis having full movement?

Katsu Kubota drove Classic's in 2010. What about Sean Walker? Did he drive it, or maybe test it?

 

To be honest Steve the more i think about it the more sceptical i get about it working!

 

Peter



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#40 f1steveuk

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Posted 11 August 2014 - 16:34

Ah, the joys of healthy debate!



#41 Charlieman

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Posted 11 August 2014 - 17:08

I'd be very interested to know the answer to that because I don't remember too much talk about controlling the CP back in those days. 

Think about those Ligiers which won early races in South America. Ironically, they were brilliant out of the wind tunnel and winter testing, but declined somewhat when engineers fiddled. I was a teenager at the time but I read enough in the press of the time to determine that centre of pressure was moving everywhere. Porpoising was an apt description.

 

And Ligier made similar mistakes running the team two years on the trot.



#42 PeterElleray

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Posted 11 August 2014 - 17:24

Think about those Ligiers which won early races in South America. Ironically, they were brilliant out of the wind tunnel and winter testing, but declined somewhat when engineers fiddled. I was a teenager at the time but I read enough in the press of the time to determine that centre of pressure was moving everywhere. Porpoising was an apt description.

 

And Ligier made similar mistakes running the team two years on the trot.

Interesting point - but i wonder how anyone would have known if that were the case - those cars weren't instrumented in the sense that we now take for granted.

 

I know that Lotus did some tests with pressure tappings that fed into a data logger, also Williams, and Tyrrell fed the same taps into a manometer on the car, not sure if Ligier were into that in 1979 or not? 

 

From my own experience of modern data logging it is still pretty difficult to get an accurate picture of CP shift, the best you can normally have confidence in is a straight line test which probably wouldn't yield much data about pitch sensitivity.

 

SO i am guessing that a lot of the conclusions reached were somewhat subjective.

 

Not saying that the cars weren't behaving as  described, or that they were not engineered back down the grid, but i have also read of concerns about the structural integrity of the pods themselves after a few races use, and would be very interested to know the real reason.

 

We need a qualified source very close to the action at the time.

 

The JS11 was never really back on terms with the FW07 Williams once that car was sorted until the redesign over the winter of 79/80. Its period as the class of the field predated the appearance of the FW07 Williams.

 

Peter



#43 Charlieman

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Posted 11 August 2014 - 18:43

Interesting point - but i wonder how anyone would have known if that were the case - those cars weren't instrumented in the sense that we now take for granted.

Ligier were well connected with French aerospace industry. so assume that their models were good. As you say, few car builders had portable data logging systems at the time. Everyone tried to build a better model than the opposition and prayed that it worked.

 


"...but i have also read of concerns about the structural integrity of the pods themselves after a few races use, and would be very interested to know the real reason."

This is like floppy monocoque anecdotes, the car being fixed by an amateur stitching the car together properly. In some cases, the anecdote is true but the Delage reinvention predates monocoques.

 

Creep? All of the forces are outside everything known for racing cars, until now. Stuff will break in extraordinary ways.



#44 PeterElleray

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Posted 11 August 2014 - 19:04

 

Ligier were well connected with French aerospace industry. so assume that their models were good. As you say, few car builders had portable data logging systems at the time. Everyone tried to build a better model than the opposition and prayed that it worked.

 


This is like floppy monocoque anecdotes, the car being fixed by an amateur stitching the car together properly. In some cases, the anecdote is true but the Delage reinvention predates monocoques.

 

Creep? All of the forces are outside everything known for racing cars, until now. Stuff will break in extraordinary ways.

 

I was thinking in terms of instrumenting the car itself, not the wind tunnel model - is that what you mean when you say model?

 

Things were a bit primitive at that time in the few tunnels i was aware of or used, no remotely controlled multi ride and rake struts, every change had to be done by hand and was not very repeatable, especially if using analogue spirit levels etc.

 

So very little 3 dimensional mapping was actually done in the tunnel. Others may have been more advanced, i am not sure.

 

I agree you have to be careful of the floppy monocque anecdotes, which is why i said i would like to know the real story, and hear it from someone qualified to retell it.

 

t wouldn't be the first time that nonsense has appeared in print and been passed down as fact...  ;)



#45 Charlieman

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Posted 11 August 2014 - 20:25

I was thinking in terms of instrumenting the car itself, not the wind tunnel model - is that what you mean when you say model?

I think we can define model as 1/4 scale or whatever. And then you mess it around at different angles.

 

A prototype is a full size car with wheels, but if Lotus had instruments on it in 1981... 

 

Which is where we are today.



#46 PeterElleray

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Posted 11 August 2014 - 20:34

I think we can define model as 1/4 scale or whatever. And then you mess it around at different angles.

 

A prototype is a full size car with wheels, but if Lotus had instruments on it in 1981... 

 

Which is where we are today.

Thanks - 1/4 scale would have been state of the art in 1981, but not for many years since..

 

As regards messing it about at different angles, its a relief to finally understand why i spent 5 years of my life , off and on, travelling to Switzerlands Emmen wind tunnel test facility .. :kiss:



#47 wilga1

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Posted 12 August 2014 - 00:38

I seem to recall that the legal dispute was over the word "CHASSIS".

 

What is the plural of "chassis"?

 

It is the same word for singular and plural.

 

Chapman's team was arguing that two chassis were allowed under the rule's wording.

 

The Court's came down in favour of the rules intention, rather than the black letter law.



#48 PeterElleray

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Posted 12 August 2014 - 08:16

yes that is correct. i always wondered if anyone involved at the time had ever dared to ask Chapman if, that being the case, where was the bodywork?

 

I think the party line was that there was none .

 

Ironic , in view of the ruling on intent that one of those Chapmanism's that has been passed down to us  is "Do what i mean, not what i say..."



#49 kayemod

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Posted 12 August 2014 - 08:36

yes that is correct. i always wondered if anyone involved at the time had ever dared to ask Chapman if, that being the case, where was the bodywork?

 

I think the party line was that there was none .

 

Ironic , in view of the ruling on intent that one of those Chapmanism's that has been passed down to us  is "Do what i mean, not what i say..."

 

"When I use a word," Humpty Dumpty said in rather a scornful tone, "it means just what I choose it to mean - neither more nor less".

 

"The question is", said Alice, "whether you can make words mean so many different things".

 

"The question is", said Humpty Dumpty, "which is to be master - that's all".

 

#50 f1steveuk

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Posted 12 August 2014 - 09:55

OT, but the Ligier was supposed to have an in built adjustment ( I recall a grainy black and white picture in GPI) that once noticed by other teams, quickly vanished, as the did the early season performance.

 

Even with the 88 being a Lotus, I just cannot see "Chunky" doing it to spite the "powers that be", but I could see him being fooled by wind tunnel figures, though Lotus had been burnt by the tunnel figures, and the track performance of the 80. The "other" version of this principle I alluded to, with the huge, one piece body/cover, had the rear wing attached to the rear of the gearbox, and winglets on the front of the monocoque. Then there was another set of winglets on the nose part of the body and further ones at the rear of the sidepod area (I am hoping to be allowed to reproduce this drawing), the purpose of these winglets, to push the one piece bodywork down on to the springs, so the the sides wouls, as before, seal the gap between the sides of the venturi, and the track. Now that I know this was pre Lotus 88 (and I am now very curious if it was post 86), it strikes me, that it WOULD have been legal, seperate chassis and body, as opposed to the 88. I don't think wind tunnel figures, in this instance, will answer the question if the 88 would have worked on track.