69 replies to this topic

[Alfisti]

When did the supercharger first come into vogue? I was surprised to learna few years ago that the supercharger has been around for so long... but i don't really know when. Also, which teams pioneered it and which used it best? Do you think it aded to the racing of the time or detracted from it??

I am interested in supercharging my car...but the compression ratio on the Alfa 2 litre is so bloody high that it would bneed decompressing... which = $$$$$$

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"Life will not break your heart, it'll crush it" - Henry Rollins.

[Michael M]

Supercharging was first introduced at aero engines during WWI. Due to lower air pressure at higher altitudes the engines got too less combustion air, which had been equalized by a supercharger. Daimler-Benz had been one of the most important aero-engine manufacturers in WW1 (and later also in WW2), so in the 20s they refined this system for automotive engines too. One of the pioneers was Prof. Porsche, who was technical director at Daimler-Benz from 1926-1928.

[Ray Bell]

As with many new things, the introduction of the supercharger wasn't seen in the same light as now. Today we see a forced-induction engine as a different entity to a normally aspirated engine, and there are class differentials or formulae to achieve some form of capacity distinction.
A 2-litre Grand Prix car of the mid-twenties was 2-litres, whether or not it was supercharged. Thus, supercharging was seen as a more efficient way of getting more power out of the same engine. Less technologically difficult... mechanical technology rather than combustion and gasflow technology taking precedence.
There were, of course, those who had the superchargers that could be cut in on demand, which is another story.

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Life and love are mixed with pain...

[gunner]

Was Daimler Benz the first to use Torbo charging on the ME 109?

Gunner

[Roger Clark]

The first racing cars to use superchargers were American Chadwicks from 1907. THey ran in the Vanderbilt Cup Races and the Savannah Grand Prize, proving fast, but unreliable. They later went on to win many smaller hill climbs and sprints.

In international racing,superchargers were banned from 1912 to 1922. THe first to race with superchargers after the war were Mercedes, who ran a 1.5litre car in the 1922 Targa Florio, and a 2litre in the 1923 Indianapolis 500.

At that time, the French GP was still by far the most important race of the year and the 2litre Mercedes complied with the regulations. However, German entries were not acceptable to the French at that time, so the first supercharged cars to run in a Grand Prix were the Fiats in 1923. They were by far the fastest cars in the race from damage caused by dust and stones drawn into the supercharger. Ironically, the race was won by a Sunbeam, which was a virtual copy of the previous years Fiat.

By the time of the next major race, the Italian Grand Prix, Fiat had redesigned the installation and the supercharger type (Roots instead of Wittig). This improved both power and reliability to such an extent that most of their rivals withdrew before the start.

At this time Fiat were undoubtedly the technical pacesetters in Grand Prix racing and many of their best engineers were poached by the opposition, including Vittorio Jano, who went to Alfa Romeo and bacame one of the greatest engineers in the history of racing.

By the 1924 French GP, almost all the serious competitors had superchargers. THe only exceptions were Bugatti, who thought it contravened the rules, and Delage, who thought that heir 12 cylinder engine would compensate for its absence.

All the early engines used the supercharger to pressurise the carburetter. The 1924 Sunbeam put the supercharger between the carburetter and the engine. This was a much more efficient arrangement: in unsuperchrgaed form the engine developed 102bhp, pressurising the carburetter it gave 115bhp, and compressing the mixture it gave 138bhp.

From that time until 1951 virtually all important races were won by supercharged cars.

[Ray Bell]

So the Chadwicks predated the ME109s by about 33 years?
Supercharging was so popular in the thirties that most racing MGs had pumps.. the beautiful 6-cyl 1100cc K3 among them. Bugatti's resistance didn't (couldn't) last, of course, then twin superchargers were used on the Alfas of the early thirties.
The next stage was double stage supercharging, which came in some time in the mid-thirties, compressing again the mixture after the first pump had done its job.. ultimately three-stage supercharging was used, but not by many.
The other development was the use of intercoolers, highly favoured by Miller... when did these originate, and with whom?

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Life and love are mixed with pain...

[gunner]

Roger Clark.

How did a Wittig supercharger work?

Gunner

[desmo]

You may be able to cheaply lower your c.r. enough by using mutiple head gaskets. It's been done before.

[Michael M]

There is misunderstanding concerning aero-engines. The ME109 of course was WW2 plane, but already in WW1 aero-engines from Daimler and Benz (2 separatate companies then) used superchargers. The compressors on aero-engines had been of centrifugal type, automotive engines mostly used rotary-wing type compressors (Roots system). Centrifugal compressors are more effective, but the additional power is only available at high revs, and it comes like a "bang", whereas Roots type compressors are more smoothly, with power increase over the whole rev range. The BRM 1.5 ltr V16 e.g. used a centrifugal supercharger, this was the reason for its phenomenal power, but also for its undrivability. All these superchargers had been driven mechanically from the engine itself, so there was of course a limit of efficiency when the power needed for their operation exceeded the power they produce.

These mechanical compressors should not be mixed up with today's turbos, which are driven by the pressure of the exhaust system. Turbos are centrifugal compressors, so very often they are mixed up with centrifugal mechanical driven compressors.

[Alfisti]

I thought it might have been Mercedes.

Desmo, not a great idea to do that to Alfa engines... all alloy engine so there is a little more flex than usual... more gaskets just ask for a blown head, especially in Ozzy heat.

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"Life will not break your heart, it'll crush it" - Henry Rollins.

[Dennis David]

It's important to note America's contribution to racing with regards to supercharging and especially turbocharging. I know that when Renault re-introduced it to F1 they leaned heavily on American experience in turbocharged cars for oval racing despite the obvious difference between it and F1.

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Regards,

Dennis David
Grand Prix History

Life is racing, the rest is waiting

[Michael M]

Alfisti:
Yes, of course it was Mercedes! Up to 1926 there had been 2 companies, one was Benz & Cie. at Mannheim, the other was Daimler-Motoren-Gesellschaft at Stuttgart. The cars of Daimler had the brand "Mercedes". In 1926 both companies merged to the Daimler-Benz AG, a name which was in operation up to the recent merger with Chrysler, and the new mutual brand for all cars was "Mercedes-Benz". However, the aero-engines never wore the name "Mercedes", before the merger it was either "Daimler" or "Benz", and thereafter "Daimler-Benz" or "DB".

Dennis:
As far I know the American word "turbocharging" - at least if we talk about the period up to 1970 - does prescribe a mechanical driven centrifugal compressor. Also the famous Miller racing engines had centrifugal compressors. When Bugatti finally decided to use supercharging, they accquired a Miller racing car to study it. They took over the DOHC, but instead for a centrifugal supercharger they went for a Roots type one.
The history of the exhaust driven turbocharger as introduced by Renault to the F1 in the 70s has nothing to do with turbocharging in the American sense. The exhaust turbo was invented by Swiss Alfred Buchi in 1915, and the first turbo in an automotive engine was introduced in 1938, in a Swiss Saurer Diesel truck engine. However, the first gasoline engine with an exhaust turbo was of American fame, in 1962 the Chevrolet Corvair Monza and the Oldsmobile Jetfire had been the first passenger cars using this system. It was not fully developed and unreliable, so dropped very soon again. The next serious attempt came from Germany, in 1973 the BMW 2002 Turbo, and in 1975 the Porsche 911 Turbo. On the racetrack, the first exhaust turbo driven engine appeared in 1972 in CanAm, the all-mighty Porsche 917/10.

[Roger Clark]

MichaelM:

Bugatti copied the miller DOHC head (as you say) for the T51, but he had already usedsupercharging on later versions of the T35 and others.

Ray: two stage supercharging was first used in 1938 by both M-B and A-U on the 3 litre cars. with the unlimited capacity engines, engine efficiency wasn't so important

[Ray Bell]

Of course, as it wasn't back when there was no parity factor for supercharging in the twenties... as for Alfisti and his original question, he might be better off getting some low compression pistons...

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Life and love are mixed with pain...

[Barry Lake]

MichaelM
Do you have some references for Americans using the term turbocharger for mechanically driven superchargers?
I don't remember ever coming across this. I felt sure they had always used the term supercharge in the correct (as we know it) sense.

[Michael M]

Barry, English is not my mother language, so of course I do not feel safe. Of course the wording "supercharged" is the general term for engines not "breathing atmospherical", but the problem with this word is that it does not define the way the pressure is produced. It may be a mechanical driven supercharger (centrifugal or rotary-wing), or an exhaust driven one. This very often leads to confusion about which system is meant. I read some articles about cars using exhaust driven chargers, like i.e. the Porsche 917/10 or 30, where it is prescribed as "turbocharged" (correctly), but others use also "supercharged". In some articles about the Miller engine and some aero-engines (don't ask for details, it was somewhere in the web) the term "turbocharged" also has been used for the mechanical driven centrifugal compressor. The compression principle of both, the exhaust turbo and the centrifugal supercharger is identical, namely by using a kind of turbine, although the drive system is completely different. May be this "turbine" is the reason that sometimes also centrifugal superchargers are called "turbochargers".

However, what I wanted to say in my posting is that contrary to Dennis' opinion the exhaust turbocharging as introduced by Renault to Formula 1 was not based on American technology, their main principle was always the mechanical supercharger, mainly the centrifugal one.

Barry, which correct term do you propose for prescribing the 3 systems of increasing the inlet air pressure of combustion engines:
- mechanical driven centrifugal
- mechanical driven rotary-wing (Roots system)
- exhaust driven centrifugal?

[Alfisti]

'Fisti is getting lost

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"Life will not break your heart, it'll crush it" - Henry Rollins.

[Michael M]

Why??

[Ray Bell]

Because he's just a kid!

The Renault F1 effort of the 70s and 80s used no mechanically driven superchargers. AirResearch and KKK turbochargers are two names I can think of in relation to this era in GP racing.

how are these for names:

Positive displacement - Roots-type or vane-type supercharger
Centrifugal - mechanically driven impeller-type supercharger
Turbocharger - exhaust driven impeller-type supercharger

Of course, there will be someone who will want greater distinction, or add another type.

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Life and love are mixed with pain...

[Michael M]

Ray, that's what I said over the Renaults. The wording "their main principle ..." refers to the Americans.
The problem is that in English for all principles the word "supercharger" is used, and if one uses "turbocharger" you cannot be sure whether exhaust impeller type or mechanical impeller type is meant.
Alfisti's reaction shows that probably a lot of people do not know what "supercharging" really is, except that it increases engine power.

[Alfisti]

Crikey i am not that bad Ray you dinosaur . My mechanical knowledge is woeful for a guy so into cars. I know a Turbo works off the exhaust and a s/chargerdoesn't and a supercharger is much smoother without the violent on/off switch affect of the turbo but a turbo will create bigger numbers.

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"Life will not break your heart, it'll crush it" - Henry Rollins.

[Ray Bell]

Well, they're the basics... but watch the dinosaur bit!

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Life and love are mixed with pain...

[Barry Lake]

To my way of thinking (developed from reading a lot of books), "supercharger" always referred to mechanically driven pumps of any type providing pressure for the ingoing gases.
These could be more accurately described, if desired, by adding "Roots type", Vane type", "centrifugal" or whatever.
I only became aware of the term "turbocharger" when the exhaust driven (fans rather than pumps) came into popular use.
Come to think of it, that's not a very good description, but that's the word people chose to use.
The only confusion, I thought arose when some people began to call turbochargers "turbo-superchargers".

[KzKiwi]

The Americans were indeed trendsetters when it came to supercharging racing cars - we have already correctly mentioned the Chadwick as the first racing car to have a supercharger fitted.

However Miller ran a car at the 1927 Indy 500 with a 2 stage centrifugal supercharger that was developed by the General Electric company. At 7800 RPM it delivered 28 lbs. per sq.in. This was 12 years before MB and Auto Union introduced the 2 stage s/c to Europe.

Perhaps one of the greatest advances in supercharging efficiency was the introduction of the intercooler, to improve volumetric efficiency by reducing the temperature of the incoming mixture. I am unsure as to exact dates but my notes mention that Frank Lockhart, another American, was the pioneer in this field Circa 1927. I am not sure if this was at Indy or on his LSR car. Can anyone assist?

[Roger Clark]

I believe that Chadwick built engines with three stage centrifugal superchargers before the first world war! He made the superchargd model for sale to the general public with a guaranteed speed of over 100mph. I don't know whether this was a road or a racing car.

Fiat fitted a crude intercooler to their late 1923 cars.

Earlier in this thread, Gunnar asked about the Wittig supercharger. It was a vane type compressor, each vane running in slots in an eccentric rotor, with it tip running against the inside of the casing. Part of the casing was hinged so that it could be swung aside,in which case the pump ceased to have positive delivery. (Pomeroy)

[KzKiwi]

Eric,
Tell me more about the intercooler fitted to the 1923 Fiat. Race details and the like?

[Roger Clark]

Regarding the Fiat intercoolers, all I can say is that they fitted them for the 1923 Italian GP when they changed from Wittig to Roots type superchargers. I would assume, but can't confirm, that they also used them for the 1924 French GP, but after that Fiat withdrew from serious racing.

[karlcars]

Not to pick too much at a nit, two-stage supercharging of Grand Prix cars was introduced in 1939, not 1938, by both Mercedes-Benz and Auto Union. The benefit that it brought was greater efficiency, in that less power was required to drive the two blowers to get the same boost as a single blower. Interestingly, Porsche designed built the experimental setup that showed the advantages of the 2-stage system, acting as consultants to Daimler-Benz.

The Indy car mentioned with the two-stage centrifugal blower was a formidable machine, the Detroit Special, financed and driven by Cliff Durant. It was based on a Miller front-drive but was not strictly a 'Miller' project. As I recall it developed more than 300 bhp from 1.5 litres.

I cover supercharging in quite a lot of detail in my new book, 'Classic Grand Prix Cars' (plug).

[gunner]

Did the Novi use a single or two stage centrifugal blower? It was one of the most powerful engines used at Indy for many years.

Gunner

[Roger Clark]

Weren't there also thermodynmic advantages; two superchargars in series being better than two in parallel as used by Alfa on the Tipo B and others.

Towards the end of the 80's, Honda were apparantly working on 2-stage turbocharging, aiming for 1500bhp in race conditions.

[Darren]

Yes, it was meant to avoid lag and still provide high boost. Hitachi were working on electrically-driven turbos to get around the problem, but I don't know how far they got.

[Ray Bell]

Why not go for something driven by braking energy? Logically, that's when the turbo isn't being fed its steady diet of hot air...

[Wolf]

I always wandered why no 4 strokes (as far as I know) never used pistons for charging (as most 2 stroke engines do- otherwise they would have to use either mechanical or turbo chargers). I guess in that manner some rules could be bent (since all the pressure increase is made by air-flow through the engine).
By the way Alfisti, if you used any kind of charger I suppose you would have to modify cooling circuit (lest you perchance considerably shortened life of your engine- even if it endured higher pressure, higher temperature of expansion cycle would reduce the strength od cylinders)

[Don Capps]

Just for the record, there was no such thing as a "Me 109." There was the Bf 109, which was the designation given to it by the Messerschmitt folks. There, I feel better...

Just looking at the articles mostly from Motor Age and Motor (the American magazine, not the British one...) that Floyd Clymer compiled for his history of the Indy 500 to 1941, the chapters covering the 1923-onward period when supercharging arrived, makes interesting reading. It is different to read the contemporary accounts versus those of the historians looking at things in retrospect.

There was a good article published somewhere in the mid-60's about the supercharging of racing cars and had a nice bit of background concerning it. Cannot remember the source to save my life...

[Roger Clark]

Wolf,

In about 1912, Hispano-Suiza built a racing engine with piston supercharger. It had two small pistons on the main crankshaft, providong air under pessure to the main cylinders. It was intended for the coupe de l'Auto, a sort of voiturette race of thetime. The engine failed on test (nothing to do with the supercharger) and was not raced in that form. It would have been the first supercharged car to apear in European racing.

[Wolf]

Dear Roger,
Thanks for useful info. But those were the additional pistons, I was reffering to the engine's own pistons, and utilizing their downward movement during expansion and intake cycles. Thus would engine have it's intake air led into the oil sump (through unidirectional valve) and led out through pressure valve to the valves. This was earlier on done with fuel-gas mixture (in 2 stroke engines), but today it would be more convinient to have fuel injected after compression of the air.

[Ray Bell]

It's generally considered that getting performance out of an engine by supercharging is less stressful than by more conventional means... that the loadings are less severe on the mechanical components.
But that's not to compare with getting as much as supercharging can produce, just a bit of a hot up with a supercharger compared to getting the same performance with bigger carbies, cams, compression boosts and (more particularly) more revs.

[Wolf]

I decided to contribute on supercharging, or 'forced induction' as Americans used to say. Before mentioned Me Bf 109* on later models (from Gustav on, I belive) used MW 50 fuel injection, which is in the case of supercharging interesting in two ways. MW 50 injected methanole-water mixture with the fuel. Methanole was used not only for its good burning properties, but for a kind of supercharging. Older among us may remember methods of reducing high body temperatures (when sick) of our elders- rubbing of alcohole on your body, and this lowering of temperature by evaporation (it's not exactly evaporation but I don't know the proper term, does word Dalton ring a bell?) of methanole was used to induce more mixture into the cylinders (lower temperature- more mass in the same space at a given pressure). This sometimes led to freezing of carbs, but they solved it quickly (carb heating). Since the air at high altitudes was so thin that it was very hard to compress (I guess it leaked from supercharger), water was added for additional mass, which then enabled easier charging.
Since we are at the issue of improving a engine performance, does anyone know why BRM P56 GP car had exhaust pipes sticking so far out (it looked beautiful, but reckon it must have been more than that)? My educated guess would be that it was for the purpose of lowering exhaust pressure (operated as a kind of airbrush).

* To Don Capps: proper designation was Me Bf 109 since the project was led by Willy Messerschmitt, in intended capacity of consultant for Bayerische Flugzeugwerke (thus the Bf designation). He took over the firm in 1931. yet kept the Bf until very late in production (he probably got to lazy to write the whole thing).

[karlcars]

It's not on topic, but the reason the BRM V8 used those vertical single exhaust stacks was that it still had a 90-degree crankshaft, which would have required a tuned exhaust system of awesome complexity (see the Indy Ford V8s, which had the same kind of exhaust in the first year). Instead they just tuned each pipe to the optimum length for best torque and stuck them up in the air. Some of the Chaparrals were the same way for the same reason. When you go to a flat or 180-degree crank you can fit each bank with what amounts to a tuned four-cylinder exhaust.

The Indy Novi was centrifugally supercharged but only single-stage. An outfit called Turbodyne has perfected a turbocharger which can be electrically driven to give some remarkable benefits. See their website, I think http://www.turbodyne.com.

[Roger Clark]

Of course the Climax V8 had a linked exhaust system, except in the rare flat crank versions. The final versions of the V8 BRM adressed the problem more elegantly with the central exhausts.

[Ray Bell]

Strange that the BRM V8 is remembered for the exhaust stacks, yet it ran without them for a great deal longer than with them. They had a variety of setups, and they had two-valve and four-valve heads, from memory, with the central exhaust mentioned above being a very neat fit on their nice and skinny monocoque cars.

[Roger Clark]

I don't think the V8 BRMs ever used 4 valve heads, although they did some development work.

The BRP-BRM that Innes Ireland drove in 1964 also had vertical exhausts, but without the megaphones. It was a very nice looking car.

[Ray Bell]

Must be that I remember the mention of the development work. Just imagine transferring those heads over to the H16!

[PhilD]

Just a thought or two. I seem to remember the 3.5 litre Bentleys having had a front mounted supercharger ( direct drive from the crank I believe) but I can't recall the period from which the ran.

An excellent book on the subject of both supercharging and turbocharging is Allan Allard's book on called Supercharging and Turbocharging (unique title) no longer in print. Lost mine. I believe he was related to the family who built the Allard car, I was a passenger in one in my teens back in the 70's most memorable.

Having built engines with both forced induction systems back in the 70's and 80's I still prefer the supercharger over the Turbo. The problem with the Supercharger was that for every 10 bhp it produced it took 3 to 4 bhp of the increase to drive the charger. The Turbo used to suffer from the dreaded Turbo lag, for those of you who have never experienced this it is really frightening to feel the power come in 5 degrees further coming out of a corner than you thought it was going to. Oops! I believe the lag problem is now cured. Lancia was at one time doing some research in to a combination of the supercharger and the turbocharger with the super being utilised at low revs and the turbo taking over when sufficent pressure had built to overcome the lag. Anyone know what happened to that idea?

[Ray Bell]

Not that idea... but another book about supercharging was written by Eldred Norman, very familiar with the subject. He double-staged the supercharging of the 1936 Maserati 6C that he rebuilt, the one he cast heads in bronze for, and in which he used the Singer rods he had to get posted from England.
He got into supercharging manufacture and wrote a handbook about it... he knew how to write, his wife was Nancy Cato, the novelist... see more about his cars in the thread 'The Cars of Eldred Norman'
The book is available from his son, Mike, at Noosaville, Qld.

[Don Capps]

* To Don Capps: proper designation was Me Bf 109 since the project was led by Willy Messerschmitt, in intended capacity of consultant for Bayerische Flugzeugwerke (thus the Bf designation). He took over the firm in 1931. yet kept the Bf until very late in production (he probably got to lazy to write the whole thing).

Sorry, doesn't fly (;) ) -- it was always the Bf 109 to the Messerschmitt folks. Only the Brits and the Yanks called it by the "Me" designator which was okay for all those designs after the Bf 110 since they were "Me" designs. It was the design office which got the credit under the German system, hence the Ta 152 development of the Fw 190 series by Dr. Tank and his design office although it was actually a Focke Wulf product. It is enough to give you headaches...

[Alfisti]

Well my next question is why aren't all engines suopercharged. What i mean is.. instead of a 3 ltr naturally aspirated engine a 2 litre supercharged.. even at mild boost would be a better option. I wonder why car manufacturers have never thought of it especially for smaller cars.

[Ray Bell]

Perhaps it would have been a feasible option in the thirties, but with technology over the past forty years it has fallen out of the bounds of probability for the average maker.
Back then some fairly popular cars had superchargers as options or standard, apart from the expensive cars like Mercedes' bigger models. There were plenty of MGs with pumps, for instance. Not sedans, however, just sporty cars.
Cost and complication are the reason.. it's less costly to just make the bore a bit bigger or the stroke a bit longer than to arrange a drive, make a pump, go through the additional tuning tests and so on.
Yes, Fiat did it, and a few others recently, but complication is the problem.

[PhilD]

Hello again,
There are some supercharged cars available for purchase, the Buick Regal is one that comes to mind. How ever the main problem with blown engines is that they tend to run extremely hot and require regular tuning. Also they like to run with the timing in advance which creates starting and idling problems.

Everything must be in perfect order for a supercharged engine to work effectively, some even use gapless pistons to prevent blow by in to the crankcase. From my own experience super/turbo chargers also like to stick bits of the cylinder head gasket to the inner wings of your vehicle.
In short there is not the demand for a vehicle of this type.

I belive that turbos are still being used extensively in diesel powered vehicles, but that's another story.

Was it Bugatti that had no cylinder head gaskets because their machining tolerances where so fine? Sadly my memory is not what it was. Perhaps some one else knows?

[Ray Bell]

I've heard that of Caterpillar... not Bugatti, I wouldn't think... but someone will know.
As for blowing the gaskets out the sides, I don't think that should be all that common if (and we're talking production engines here, remember) compression ratios and blower boost levels are kept reasonable.