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Why were there no supercharged Grand Prix cars 1966 to 1976?


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#1 SGM

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Posted 19 March 2019 - 22:42

As far as I'm aware, supercharged 1.5 litre engines were eligible right from the start of the new 3 litre era but it took until 1977 before Renault exploited the rule. Usually in F1 after a major change in regulations there is a period of experimentation by teams until the way forward becomes clear and then all teams follow suit. This certainly happened, engine wise, during 1966 to 1968 but I am surprised no one thought of supercharging one of their 1965 1.5 litre engines, even as an interim measure, for the new formula. When you consider Alfa Romeo were claiming over 400 horsepower from their 1.5 litre Grand Prix cars in the early 1950s and the V16 BRM  (according to the dyno print out in the Karl Ludvigson BRM book) was capable of over 600 horsepower, it seems strange to me that teams didn't at least experiment with supercharging, particularly when you factor in the advances in engine technology in the meantime. After all, less than 340 horsepower was needed to win the championship in 1966 and 1967, but of course hindsight is always 20/20.

 

Obviously, the supercharger would have to have been a bespoke unit which would have been an expensive exercise and perhaps this is what turned the teams off? Or were they just gun shy after the BRM V16 problems?

 

 

Perhaps some teams did consider supercharging but it is just not well documented? 



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#2 Tim Murray

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Posted 19 March 2019 - 23:43

These earlier threads may be of interest:

1966 3 litre Formula One

Why did it take until 1977 for turbos to reach F1?

The main points emerging from those threads were:

In 1966 F1 engines had to run on pump fuel. Thus any supercharged engine would have been denied the internal engine cooling provided by the fancy alcohol brews used in the previous supercharged era. This would have considerably restricted power compared to the earlier supercharged engines.

The engines used in the 1.5-litre formula were getting toward the limits of their development by 1965 and would have had difficulty withstanding the extra stresses provided by supercharging without a significant amount of redesign and redevelopment (see DCN’s post quoted below).

All engine development over the previous fifteen years since 1951 had been on unsupercharged engines. Anyone planning a supercharged engine for 1966 would have had to relearn supercharging technology.

And, as DCN said in the latter thread above, BRM did seriously consider supercharging, but rejected the idea:


... BRM ran an investigation on a possible 1.5-litre supercharged V8 for the 3-litre Formula - half of the original V16 engine tidied up with more sensible crankshaft arrangements - but no way could they make the calculations look as promising as a true 3-litre naturally-aspirated unit. Seeking maximum revs to burn maximum fuel/air mixture, they adopted the 16-cylinder idea and packaging considerations led Tony Rudd (fatally) down the coupled-crankshaft H-layout route. A straightforward blown version of the small P56 V8 was a non-starter due to head seal (against internal pressures) and other considerations, and a supercharged engine was always going to be less fuel efficient and probably less drivable...they thought.

DCN



#3 Sisyphus

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Posted 20 March 2019 - 03:20

Tim is exactly right--the 1.5 liter engines wouldn't have been suitable as designed because they couldn't have withstood the additional BMEP that a proper turbo would have easily provided.  They were already maxed out on the amount of power they could produce and stay together for the length of a race.  The limit on power for a turbo engine is the strength of the engine--you can keep getting higher power with higher boost until it fails mechanically or thermally somewhere.

 

But the other equally valid point is that at the time suitably sized turbos didn't exist.  The available ones were too big for a 1.5 liter engine to have the kind of transient response you would have needed in F1 to be competitive with a naturally aspirated 3 liter engine.  By the late 70's, production turbos had gotten smaller plus variable nozzle turbines (for quicker response) were available to start F1 development with.  At that time, an F1 engine manufacturer wouldn't have been able to develop a suitable turbo themselves, IMHO.

 

My comments are based on having spent my career in turbos including being peripherally involved in some of the F1 work.



#4 Ray Bell

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Posted 20 March 2019 - 03:45

Superchargers also require power to drive them...

 

So the power required to equal the 3-litre naturally aspirated engines would have been more like 450hp.



#5 Henri Greuter

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Posted 20 March 2019 - 07:59

Superchargers also require power to drive them...
 
So the power required to equal the 3-litre naturally aspirated engines would have been more like 450hp.



As for a figure about what it took to power a supercharger: the Prewar Mercedes V12s superchargers took some 100 hp off the flywheel.and that left some 450 hp for axle driving duties.
I have no data on what the power consumption for the superchargers was for the more suitable for comparison 1.5 liters of Alfa Romeo (Alfetta 158&159) and of course that frightening BRM V16. Though the latter had centrifugal blowers that in general require less power)

Other then that, nothing substantial to add to all explanations. Other than perhaps bring up in memory what was likely the only time that turbos were tried in racing before 1966: the 1952 Cummins Diesel ast Indy. That was a hefty & heavy 6.6 straight 6 diesel engine. I have spoken Freddie Agabashian who drove that car and he told me that the reaction time of the engine and turbo was about 10 seconds before he got full power!

Curiousy, it was indeed in 1965 that experiments were carried out with Offenhauser Indycar engines to develop a 2.8 liter turbocharged version of it, the atmo version was a 4.2. And that with the benefit of the allowed use of methanol fuel. But it was a massive undertaking to make it work. There is one story going that a driver who made his first lap came back instantly and wondered if he had blown up the engine because of the sudden power burst, something not unusual for an engine to produce its most power ever in the last seconds for blowing up.


Though one thought: the ratio between blown and atmo in F1 was 2, while in Indycars is was 1.5 and in later years in endurance racing for atmo (likeFf1) 3 liters while blown engines were allowed 2.14 liter thus a factor 1.4. Now had this factor of 2 within F1 been lowered and got closer to the 1.4 as in endurance racing, maybe a factory would have given it a try way before Renault began experimenting in '75.

I think this very unfavorable ratio might have been of influence as well....

Edited by Henri Greuter, 20 March 2019 - 08:00.


#6 Ray Bell

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Posted 20 March 2019 - 10:59

You're probably right there, 1.4 was an across-the-board equivalency ratio in all but F1...

 

The ratio in F1 up to 1950 was 3:1, of course, while there was a provision in the 1954 F1 rules with an equivalency ratio of 3.333:1.



#7 Charlieman

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Posted 20 March 2019 - 11:40

I don't know whether it was a factor for Renault in 1975, but computer modelling of internal combustion engines took a big leap forward at that time. It would have been significant for some of the manufacturers who followed.



#8 Henri Greuter

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Posted 20 March 2019 - 11:54

I don't know whether it was a factor for Renault in 1975, but computer modelling of internal combustion engines took a big leap forward at that time. It would have been significant for some of the manufacturers who followed.


forgive me for bringing in the Offy another time ....

The original Offy had a fairly large valve angle but that angle got reduced over time. Main man behind this was veteran engine man Art Sparks who had been inspired by some thoughts on cylinder head designs in Germany. He persuaded the Drake Engineering to follow that and their designed, the fabled legendary Leo Goossen started the designs. But he died before the plans were finished and that was done by others. The resulting engine was named Drake-Goosen-Sparks or in short DGS. There was not enough money to built such engins in large numbers and then the Pat Patrick Racing team fundedn them and ad an exclusive deal on those engines, Patrick used them from 1975 on. Drake Engineering did release another version of the Offy with a slightly difrent valve angle than that of the DGS, that one was the Drake-Offy which was available for all takers. One of those won the last ever Indy 500 for a fourcyliner Offy-dynasty engine in '76. The last ever honorable finish in the 500 was in 1980 when one of the discarded Patrick built Wildcat-DGS cars finished third with Gary Bettenhausen driving.
This transision to smaller valve angles made the Offy gain a lot of power again. But other later rule changes related with boost pressure made the fourcylinders chanceless against the Cosworth DFX.

I have no idea if such events and inspirations also was used on the later F1 turbocharged engines. But maybe we are talking about the same trend.

Edited by Henri Greuter, 20 March 2019 - 12:23.


#9 Ray Bell

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Posted 20 March 2019 - 12:18

Valve angles coming in must have been a part of the move towards universal 4-valve arrangements...

This made it so much easier to close in the chamber and still have a spark plug in the middle.

By the turbo era I would think the only divergence from 4-valve was perhaps 5-valve.

#10 Henri Greuter

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Posted 20 March 2019 - 12:30

Valve angles coming in must have been a part of the move towards universal 4-valve arrangements...

This made it so much easier to close in the chamber and still have a spark plug in the middle.

By the turbo era I would think the only divergence from 4-valve was perhaps 5-valve.




Not mentioning the fact that due to the smaller valve angle the crown of the piston could be lowered and thus its (reciproking) mass

At home I have the piston of such a late Drake Offy and it's heavy and big....


I never have heard anything about f1 turbo engines with 5 valves.
The only `Fivers` I can name out ot the top of my head are F1 engines by Ferrari and Thickworth(sic ??)-Judds used by Lotus one year. And at Indy there was talk about a new version of the Alfa Romeo V8 to be introduced in 1990 that supposedly had 5 valves. But I never found out if these have been used at all.

Edited by Henri Greuter, 20 March 2019 - 12:32.


#11 Ray Bell

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Posted 20 March 2019 - 12:52

Somewhere along the line I recall that Yamaha 5-valve head designs were used on something or other...

I doubt that any turbo engines had 5-valves, but they were of the turbo era.

#12 Myhinpaa

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Posted 20 March 2019 - 13:04

Ford also encouraged Cosworth to try 5-valve heads on the DFV that Yamaha should develop during 1987.

 

It didn't go very well, it ran into all sorts of problems and Yamaha returned the finished engine very late.

When Cosworth put it on their dyno it produced even less power than their current 4-valve version.



#13 Pat Clarke

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Posted 20 March 2019 - 13:09

In Motorcycle racing, both Superbikes and Moto GP, it was clearly shown that Yamaha chased up the wrong tree with 5 valve heads.

One superbike tuner said he could raise the compression to gain torque, but then the Yammy wouldn't rev. Or lower the compression ratio so the engine would rev but lacked torque. In both cases the result was uncompetitive horsepower. 

When Yamaha went back to a 'conventional' tumble swirl 4 valve head, the torque and RPM returned and Yamaha could win races.

 

Pat



#14 Henri Greuter

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Posted 20 March 2019 - 13:46

Somewhere along the line I recall that Yamaha 5-valve head designs were used on something or other...

I doubt that any turbo engines had 5-valves, but they were of the turbo era.



Now you mentioned it, I also vaguely remember Ymaha doing something with 5 valves. No idea anymore however on what type of engine.

I forgot to mention it but that Ferrari F1 engine I remember as a `fiver` was one of the earlier V12s

#15 Michael Ferner

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Posted 20 March 2019 - 14:00

It should perhaps be remembered that Peugeot built a five valve engine in 1920 already. Didn't work then, either.

#16 ensign14

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Posted 20 March 2019 - 14:33

Haven't been any since 1976, either, have there?  Just turbocharged...



#17 Tim Murray

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Posted 20 March 2019 - 14:50

Supercharging is supercharging, whether the compression device is driven directly by the engine or by a turbine (or other mechanism, eg Comprex) in the exhaust stream.

#18 Henri Greuter

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Posted 20 March 2019 - 19:05

It should perhaps be remembered that Peugeot built a five valve engine in 1920 already. Didn't work then, either.

 

 

Can you by chance tel where I can find more info on that, please?



#19 Bloggsworth

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Posted 20 March 2019 - 19:19

Ferrari initially tried Brown Boveri & Cie's Comprex turbocharger with little success, I guess the rapidly changing expected powerband was too wide for a system which used pressure wave resonance to make it work, in addition, it was also driven by the crankshaft and absorbed engine power. Gas recirculation was also a problem.


Edited by Bloggsworth, 20 March 2019 - 19:27.


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#20 Henri Greuter

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Posted 20 March 2019 - 19:20

Allow me one thought about my `sweetheart` engine, the Novi V8 Indy.

 

Funny enough, coincidence or not, from 1952 on, blown engines (Let's phrase it in general to please our fellow poster Ensign14 .... ) disappeared from F1 for a long time. At the same time, at Indy the blown engines also went out of fashion from 1953 on with the lone exception being the Novi V8 (Centrifugally blown) and a few attempts araound 1958 by Herb Porter with a centrifugally blown Offy.

Thanks to the introduction of the blown Offies from 1966 on, initially bocht Rottsblown and turbocharged, later on only turbocharged, blown engines began to make a come back within racing again slowly. Ironically, the final year in which the Novi qualified and was raced at Indy, was 1965, the Novi engined car of 1966 failed to qualify.

 

This makes the Novi V8 literally the only link that bridges the first era of classic supercharged engines that ended in 1951 and the era of the turbo that started in 1966 by bing used in a kind of internationally important racing category worldwide within that period 1952-1965.



#21 Tim Murray

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Posted 20 March 2019 - 19:23

Can you by chance tel where I can find more info on that, please?


This earlier thread contains a lot of useful info, although it appears that Peugeot didn’t release many details:

1920 Peugeot type designation?

#22 Henri Greuter

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Posted 20 March 2019 - 19:30

This earlier thread contains a lot of useful info, although it appears that Peugeot didn’t release many details:

1920 Peugeot type designation?

 

Thank you Tim



#23 PayasYouRace

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Posted 20 March 2019 - 21:54

Supercharging is supercharging, whether the compression device is driven directly by the engine or by a turbine (or other mechanism, eg Comprex) in the exhaust stream.

 

Or indeed, an electric motor, as on today's F1 cars.

 

Anyway, on the subject of the thread. Weren't the supercharged Alfas of the early 50s extremely thirsty on fuel? I'm sure I've read that part of the competition in those first WDC years came from Alfas having to make pit stops for fuel while the Ferraris and others with 4.5 l NA engines could go longer. Would that have influenced the designers of the 60s?



#24 Henri Greuter

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Posted 20 March 2019 - 22:12

Or indeed, an electric motor, as on today's F1 cars.

 

Anyway, on the subject of the thread. Weren't the supercharged Alfas of the early 50s extremely thirsty on fuel? I'm sure I've read that part of the competition in those first WDC years came from Alfas having to make pit stops for fuel while the Ferraris and others with 4.5 l NA engines could go longer. Would that have influenced the designers of the 60s?

 

 

The extreme thirst of the Alfas was also caused because of them using a blend that contained a large %% of methanol. And for the same power output of an engine, it needs a larger volume on methanol than gasoline.

 

Edit:  Alfa also used extreme amounts of fuel being rushed through the cylinders as an internal coolant.  EmdEdit

 

But I think that the major reason has already been mentioned. it simply was not possible yet in '66 to make a 1.5 liter run on gasoline and turbo or a mechanic blower and produce as much power as a atmo 3 liter due to temperature issues. Intercooling was a little known art at that time and Renault made a lot of progress once they introduced those, as had Porsche on their '74 Carrrera Turbo RSR.

And even the later F1 turbo's `cheated` with the fuel rules by creating blends that were legal and had the octane ratings as required whiel the blends didn't contain hardly, if any octane at all, BMW being the culprit of that `crime`. Without those fuels the power output of the '84-86 engines would likely not have been as high as they were.


Edited by Henri Greuter, 20 March 2019 - 22:13.


#25 Vitesse2

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Posted 20 March 2019 - 22:19

By the early 50s the Alfettas were supposedly returning figures of just 1.7mpg. That was of course on 'dope' - and in comparison the 3 litre Mercedes Benz W154s had managed about 2.8mpg.

 

When the French made a (rejected) Formula proposal in 1946, they wanted to specify what was more or less 'pump fuel', which the British press reckoned would reduce the power output of the ERAs and Alfettas by at least 50bhp.



#26 Pat Clarke

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Posted 21 March 2019 - 02:01

Ferrari initially tried Brown Boveri & Cie's Comprex turbocharger with little success,

I hate to be a pedant Bloggie, but the Comprex is most assuredly not a turbocharger.

It is best described as a 'pressure wave supercharger' using physics not unlike the expansion chamber exhaust on a two stroke engine.

The 'paddle wheel' does not compress the mixture but rather, it traps the air, compressed by the exhaust pressure and some exhaust gas, in packets before delivering them to the intake system. The wheel timing is supposed to feed only air to the intake, the port closing before exhaust gas is admitted. This exhaust is then dumped

Like a two stroke scavenging system, there is a mixing of intake air and exhaust gas into the engine, kinda like unwanted exhaust gas recirculation

An interesting technical solution, but one that was shown to be unsuitable for the application.

 

You can read more here   https://www.revolvy....ve-supercharger

 

Pat



#27 Ray Bell

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Posted 21 March 2019 - 06:53

Could I suggest that intercoolers, though not fully developed at that stage, were well known in the forties?

 

I seem to recall seeing pictures of intercoolers on pre-war cars. Not that intercoolers would cool the engines or combustion chambers, rather they cooled the charge so it would expand more on firing.

 

Or so I recall reading...



#28 john aston

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Posted 21 March 2019 - 07:15

The only time it might have been seriously considered was in late 65 -Dutch GP 67. After DFV 's debut such huge leaps were being made with tyres and aero , not to mention the seismic intervention of Cosworth's finest that there was already enough on every team's plate for the immediate future. Who cared about alternative power when the DFV had bhp to give away , and who cared about funding a research programme into a 2 stroke turbo diesel W9 when you could buy a box fresh DFV for £7500 ?

 

From 68 until the Renault's debut(and more like  2-3  years later) power wasn't really an issue - it didn't win many races  , cost a fortune and distracted your designers from getting the 'something for nothing' bonus from aero.  


Edited by john aston, 21 March 2019 - 09:29.


#29 Bob Riebe

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Posted 21 March 2019 - 07:29

Perhaps the fate of the Novi was on more than a few minds.



#30 Michael Ferner

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Posted 21 March 2019 - 07:59

Thanks, Tim, for sparing me the trouble to go through my archives to find info on that Peugeot failure of an engine! :)


Intercoolers were, apparently, invented by Frank Lockhart during the winter of 1926/'27. They were certainly in wide use during the last years of the 1.5-litre formula in the US.

The Novi is a good example to understand why designers were not very keen on supercharging in the sixties: too complicated, too heavy, too thirsty, too hard on tyres etc. In a 1968 book I have explaining the then current Formula One, one short half-sentence is enough to mention the supercharging option - something like "nobody in their right minds will think seriously about this option", or somesuch (from memory).

#31 Henri Greuter

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Posted 21 March 2019 - 08:48

Could I suggest that intercoolers, though not fully developed at that stage, were well known in the forties?
 
I seem to recall seeing pictures of intercoolers on pre-war cars. Not that intercoolers would cool the engines or combustion chambers, rather they cooled the charge so it would expand more on firing.
 
Or so I recall reading...

 
 

Thanks, Tim, for sparing me the trouble to go through my archives to find info on that Peugeot failure of an engine! :)


Intercoolers were, apparently, invented by Frank Lockhart during the winter of 1926/'27. They were certainly in wide use during the last years of the 1.5-litre formula in the US.

The Novi is a good example to understand why designers were not very keen on supercharging in the sixties: too complicated, too heavy, too thirsty, too hard on tyres etc. In a 1968 book I have explaining the then current Formula One, one short half-sentence is enough to mention the supercharging option - something like "nobody in their right minds will think seriously about this option", or somesuch (from memory).



The best examples I recall about intercooling being taken serious were in the mid 20's on the supercharged Millers and Duesy's of the era.
I can't recall later engines giving that serious attention too it. I think that it is fair tosay that the knowledge on that was better in the USA than within Europe at that time. But that might also have something to do with the fact that in Eurpe the Roots blowers were allmighty while in the USA for the ovals the centrifugal superchargers reigned supreme.

As much as I love the Novis, I am among the first to admit they were pieces of wrong engineering. If there was potential within the engine, it was searched for in the worng manner. Curiously enough, the Clymer yearbook of '67 contains an article on Leo Goossen in which he states that according him the Novi would be the best engine of them all if properly developed and maintained.

As for the 1968 comments, I think that it is fair to mention that such was indeed the case for the current rules, knowledge of the time and the technical abilities. Hat the handicap factor been more favourable than 2, things could have been much different.

#32 GreenMachine

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Posted 21 March 2019 - 09:57

Intercooling was featured on many WW2 aero engines.



#33 Henri Greuter

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Posted 21 March 2019 - 10:29

Intercooling was featured on many WW2 aero engines.


In the postwar US single seater racing scene there was a lot of use of aeroplane related hardware and technology. A number of chief mechanics and drivers of that early postwar era had been in the air force during the war.

Herb Porter, the chief mechanic who did work on supercharged Offies in the 50's had been working on B29 (Bomber) engines, which had turbochargers. it is said that his experience from that time helped him to give the Offy a try with turbocharger in late '65 and '66.

#34 Allan Lupton

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Posted 21 March 2019 - 10:29

 
  I think that it is fair tosay that the knowledge on that was better in the USA than within Europe at that time. But that might also have something to do with the fact that in Eurpe the Roots blowers were allmighty while in the USA for the ovals the centrifugal superchargers reigned supreme.

Roots blowers are/were inefficient but common as they have a simpler speed characteristic than centrifugal, so are more suitable for the road racing duty. The centrifugal gives higher supercharge but is more suitable for constant speed duty, such as aviation or oval racing. BRM showed why centrifugal and road racing don't mix.

What isn't obvious is why the various positive displacement true superchargers (those which actually compress, such as Zoller, Cozette, Powerplus, etc.) found little favour except in small engines.

 

Intercooling was featured on many WW2 aero engines.

Yes and in that context it referred to a cooler between stages of a two-stage supercharger - the cooler between supercharger and engine was an aftercooler. In the simpler world of cars that latter has become "intercooler".



#35 GreenMachine

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Posted 21 March 2019 - 10:34

Thanks Henri :blush: Allan, I had forgotten that detail :up:


Edited by GreenMachine, 21 March 2019 - 21:36.


#36 Charlieman

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Posted 21 March 2019 - 11:52

I think we have to consider the technical and sporting factors which inspired the rules for 1966. The 1.5 litre cars are stunning achievements but the engine is highly stressed. Tyres had improved considerably and teams had started to experiment with 4WD. Nobody anticipated that tyres would improve so much or that wings would be "discovered" The rules were opened up for bigger, lower stressed engines which would generate enough power to make conventional F1 designs tricky to drive. Other categories had bigger engines making more noise. The rule makers would have recognised that Ferrari and others would build highly stressed multi cylinder engines, and that their cost and complexity would make simpler designs attractive and competitive (To finish first, first you must finish). When did the rule makers provide an equivalence formula for turbine engines?

 

I have no idea how the factor of two was conceived for compressed aspiration engines. Were the rule makers picking a number based on past practice and performance?

 

The first few years of the 3 litre F1 rule period were technically fascinating. The first two driver championships were won with a comparatively simple V8, and cars using stretched 1.5 litre engines were surprisingly competitive. 4WD experiments boomed, but slicks and wings changed everything. The DFV engine arrived at the right time to exploit the latter developments. Colin Chapman and Lotus raced turbine engine cars, and that challenges the assumption that a V8 (or V12 or H16) were good enough.



#37 Charlieman

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Posted 21 March 2019 - 12:41

We also have to look at the German racing car experiments with turbochargers. I'll skip the Can-Am Porsche 917 other than to remark that the development team created a turbo engine car which was drivable on road circuits. To me, the big thing was when Porsche raced a turbo 911 Carrera in prototype categories in preparation for the Group 4/5/6 rule changes. After showing that it worked, Porsche used the knowledge to build the 934, 935 and 936 where the factor of 1.4 applied for turbos. They used the technologies which made turbo engines successful in F1 -- intercoolers and twin turbos -- with a few others (e.g. electron beam welded cylinder heads to avoid gasket failure). The only mistake Porsche made was to assume that a factor of two made F1 turbo engines uncompetitive.

 

BMW were another early turbo adopter for GT racing. Sadly I have read little about the technology.

 

A question about twin turbos in F1. Sequential or banked on a Vee engine?

---

When Renault started their F1 turbo engine project they would have known about prototype and GT racing. Renault knew a lot about F2 racing. They could not have known that the Lotus 78 wing car and later ground effects cars would be so significant. I wonder what might have happened if Renault had pulled the plug in 1978, announcing that Porsche's predictions were right.

 

This evening, lift your glass to Jean-Pierre Jabouille -- the first winner in a turbo engine car, in a Renault at the the French GP. It was a great moment. But TV cameras and the eyes of viewers were on that remarkable battle for second place.



#38 Cavalier53

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Posted 21 March 2019 - 20:51

Returning to Formula 1, of course there was the DB 750 cc FWD that started the non-WDC Grand Prix de Pau in 1955:

https://forums.autos...harged-f1-cars/

Its' Roots blown Panhard boxer may not have been exceptionally powerful, but it pulled little weight. One finished, a mere 18 laps down from the winning 250F that covered 110 laps. Could it turn up in Pau this year - I might....

with all the arguments already posted above, fuel consumption and thus starting weight must have been a major consideration for anybody seriously contemplating any form of supercharging. Did not Chris Amon mention the terrible handicap of the starting fuel weight when he was driving for Matra, in one of his last interviews?

To quote my beloved Delsaux Francorchamps 1948-1960 (the book, I hasten to add) on the 1951 Alfa:
- 320 liter triple tanks
- the Alfetta now produces 425 HP, accompanied by a 50 % increase in fuel consumption
I still have to work out the actual consumption for comparison in the BRM fuel consumption thread.

Bottom line: it is not just HP numbers that make an engine a race winner. Capable engineers must have realized in 1966, well before I did.

#39 Lee Nicolle

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Posted 21 March 2019 - 23:25

Could I suggest that intercoolers, though not fully developed at that stage, were well known in the forties?

 

I seem to recall seeing pictures of intercoolers on pre-war cars. Not that intercoolers would cool the engines or combustion chambers, rather they cooled the charge so it would expand more on firing.

 

Or so I recall reading...

WW2 plane engines used air to air and air to coolant variants. Both s/c and turbo which the Yanks preferred.

Though that was ofcourse to give the engines atmospheric ability, eg ground level and 30000 feet the same available power.

As well as short term, take off power for heavily laden bombers.

I read recently that 617 Lancasters with the 10 ton bomb weighed about the same as the bomb.And accounts of the period had 617 Lancs extremely modified both in the frame and engines. 

Though with those bombs hanging out the bottom needed the power to get off the ground and defeat the drag at altitude.


Edited by Lee Nicolle, 21 March 2019 - 23:36.


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#40 Lee Nicolle

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Posted 21 March 2019 - 23:41

Returning to Formula 1, of course there was the DB 750 cc FWD that started the non-WDC Grand Prix de Pau in 1955:

https://forums.autos...harged-f1-cars/

Its' Roots blown Panhard boxer may not have been exceptionally powerful, but it pulled little weight. One finished, a mere 18 laps down from the winning 250F that covered 110 laps. Could it turn up in Pau this year - I might....

with all the arguments already posted above, fuel consumption and thus starting weight must have been a major consideration for anybody seriously contemplating any form of supercharging. Did not Chris Amon mention the terrible handicap of the starting fuel weight when he was driving for Matra, in one of his last interviews?

To quote my beloved Delsaux Francorchamps 1948-1960 (the book, I hasten to add) on the 1951 Alfa:
- 320 liter triple tanks
- the Alfetta now produces 425 HP, accompanied by a 50 % increase in fuel consumption
I still have to work out the actual consumption for comparison in the BRM fuel consumption thread.

Bottom line: it is not just HP numbers that make an engine a race winner. Capable engineers must have realized in 1966, well before I did.

The telephone number turbo horsepower is generally far less useable. A lack of driveability generally coupled with lack of reliability.

Better these days of course.

Tough our lamented current F1s with turbo 1500s with then electric motors as well.  Heavy and for all the money spent slow.



#41 Bloggsworth

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Posted 22 March 2019 - 14:33

I hate to be a pedant Bloggie, but the Comprex is most assuredly not a turbocharger.

It is best described as a 'pressure wave supercharger' using physics not unlike the expansion chamber exhaust on a two stroke engine.

The 'paddle wheel' does not compress the mixture but rather, it traps the air, compressed by the exhaust pressure and some exhaust gas, in packets before delivering them to the intake system. The wheel timing is supposed to feed only air to the intake, the port closing before exhaust gas is admitted. This exhaust is then dumped

Like a two stroke scavenging system, there is a mixing of intake air and exhaust gas into the engine, kinda like unwanted exhaust gas recirculation

An interesting technical solution, but one that was shown to be unsuitable for the application.

 

You can read more here   https://www.revolvy....ve-supercharger

 

Pat

 

Maybe I'm going mad, but I think I said that....



#42 Tom Glowacki

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Posted 22 March 2019 - 16:23

On a more mundane level; Coventry Climax was out of racing, nothing was going to keep Ferrari from racing a 3 litre V-12, and BRM thought they had a better idea.  Unless some newcomer came in with a turbo, there was nobody to do it.  Weslake, McLaren and Repco had neither the resources nor the inclination and Maserati thought they had an off the shelf answer.



#43 Michael Ferner

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Posted 22 March 2019 - 20:54

Oh, haven't we recently learned how easy it would have been to be a second Cosworth on the grid? Surely, that must be valid for a second Renault (and ten years earlier), too!

#44 SGM

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Posted 23 March 2019 - 07:46

My original post was aimed more towards the 1965/66 change over period and the points raised about having to run non-alcohol fuel and the fact that the then current 1.5 litre engines weren't mechanically strong enough seem to be two of the most likely reasons not to go the supercharged route at that time. If you had to build a new engine from scratch you might as well go the three litre route than waste time and money on an unknown quantity. 
 
Would water injection have been legal in 1966? This would have certainly gone a long way toward helping the power output. From memory water injection was also used in WW2 aircraft, but don't quote me.
 
Could the projected output of the three litre engines have been overly optimistic leading teams to think a blown 1.5 wouldn't have been competitive? Perhaps, going off the output of the 1.5 V8's, they thought 420 to 440 horsepower would be required? In reality, it took many years to reach that mark and in fact a blown 1.5 may have been more than competitive in hindsight.


#45 Charlieman

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Posted 23 March 2019 - 09:55

Oh, haven't we recently learned how easy it would have been to be a second Cosworth on the grid? 

Well you could always choose to have your Cosworth tweaked by Nicholson-McLaren or Hesketh or John Judd. In 1969, their first season using the DFV, Jack Brabham and Ron Tauranac added their own improvements which were adopted by Cosworth when discovered. Even the Hewland gearbox received attention by McLaren (and Lotus?). The thing about the DFV/Hewland standard package was that it provided a baseline from which improvements could be measured.

 

 

My original post was aimed more towards the 1965/66 change over period and the points raised about having to run non-alcohol fuel and the fact that the then current 1.5 litre engines weren't mechanically strong enough seem to be two of the most likely reasons not to go the supercharged route at that time. If you had to build a new engine from scratch you might as well go the three litre route than waste time and money on an unknown quantity. 
 
Would water injection have been legal in 1966? This would have certainly gone a long way toward helping the power output. From memory water injection was also used in WW2 aircraft, but don't quote me.

 

 

I think you underestimate the importance of fuel consumption at the time. The rules had changed from incredibly light 1.5 litre cars to very light 3.0 litre cars, and starting weight was heavily determined by fuel load. Whether or not water injection was permitted (and the rules were very liberal), it would have added to weight and complexity. The cars which were most successful from 1966 were those which were simple and light, including the first Lotus 49s.



#46 Ray Bell

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Posted 23 March 2019 - 10:57

Further to recollections of pictures of intercoolers...

 

Were not Millers carrying large intercoolers in the thirties?



#47 bradbury west

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Posted 23 March 2019 - 12:44

As was the Miller built Preston Tucker Special post war.
Also bear in mind the pioneering use of an exhaust turbo on the original Halford Special from the 1920s, albeit later changed for a conventional blower, the design, build and development of this car being a fascinating story in itself. We are fortunate enough to see it occasionally at Goodwood FoS.
Roger Lund

Edited by bradbury west, 23 March 2019 - 12:57.


#48 Vitesse2

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Posted 23 March 2019 - 12:57

As was the Miller built Preston Tucker Special post war.
Roger Lund

Which was actually the one remaining (of three) Gulf-Miller RE4 chassis, the other two having been wrecked.



#49 Roger Clark

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Posted 23 March 2019 - 15:58

Pomeroy, in The Grand Prix Car, Vol 2, says that the 1923 Fiats, as modified for the Italian Grand Prix, had intercoolers between the supercharger and the carburettor. I’m not aware of any endorsement of this.

#50 RCH

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Posted 25 March 2019 - 10:05

I recall being disappointed as a 16 year old that no one chose the supercharged route back in 1966. I had, sort of, worked out the reasons for it as explained here over subsequent years but still wonder whether a lightly supercharged V8 BRM or Climax would have been a better stopgap than an increase in capacity to 2 litres.

 

It's been asked why a 2:1 equivalency. It seems to me this was a mere matter of convenience, without the benefit of the thinking that has gone on here it would seem a simple answer to how to produce an engine for the new formula without the bother of building a new 3 litre unit. Maybe BRM and Climax would add superchargers to their existing units, maybe BRM would resurrect their fabled V16? We know now that these ideas weren't practical but would the FIA have been thinking that deeply in the '60's?

 

Changing the subject ever so slightly something that has always puzzled me was the Flat 16 Climax engine. Why would a down to earth English Midlands company like Coventry Climax build such a complicated unit knowing that it almost certainly would never be raced? Makes no sense to me unless they knew something, had some plan which would have made sense but disappeared with the Climax withdrawal.