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1.5 litre, turbocharged, 2 stroke F1 engine - 1974-75


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#1 Doug Nye

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Posted 03 October 2006 - 19:15

Here's a strange one.

Does anyone have any recollections of ever hearing about, reading about - or indeed (best case) of having been involved as part of a compact team of British-based engineers developing a 1.5-litre turbocharged 2-stroke Formula 1 engine as early as 1974-75?

DCN

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#2 Paul Rochdale

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Posted 03 October 2006 - 20:42

In the Donnington Motor Museum, there is on display an engine made from four or more 250cc Ariel Arrow motorcycle engines. It wasn't turbocharged and probably didn't reach 1500cc. Sorry, I'll go away........ :confused:

#3 Bonde

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Posted 03 October 2006 - 21:04

I recall some mention and seeing a cutaway of an opposed piston, twin coupled crank shafts air-cooled flat eight turbocharged two-stroke F1 project ca. 1977, but I can't for the life of me remember where I saw it, other than in some motoring journal in a library. Now, trying to recall what journal (if it was indeed a journal) and when will keep me awake all night!

#4 2F-001

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Posted 03 October 2006 - 21:06

Paul - that was six engines (making 1500cc) and found a home for a time in a Lotus 23. We've discussed it here several times in the past. Do a search for 'Rotorvic' to find more.

I have just a vague recollection of hearing mention of such a thing, Doug, but really can't remember what or where...
hopefully others can recall as it does sound intriguing.

#5 David Beard

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Posted 03 October 2006 - 21:14

Originally posted by Doug Nye
Here's a strange one.

Does anyone have any recollections of ever hearing about, reading about - or indeed (best case) of having been involved as part of a compact team of British-based engineers developing a 1.5-litre turbocharged 2-stroke Formula 1 engine as early as 1974-75?

DCN


Would a turbo 2 stroke actually work? Putting a turbine in the exhaust stream isn't exactly going to be of assistance to the extraction process, like an expansion chamber. Has there ever been a turbocharged 2 stroke? I think not.

Are you sure we shouldn't be talking about a supercharger, Doug? Mechanically driven forced
induction would have been a nice idea for a 2 stroke 1.5 F1 engine. (with very big fuel tanks though!)

#6 FerrariV12

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Posted 03 October 2006 - 21:24

I vaguely remember hearing about this sometime, somewhere, quite a while ago. Don't remember exact details, I think it was definitely supercharged though.

#7 fausto

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Posted 03 October 2006 - 21:39

I remember I read something on the Italian press, Husqvarna possibly involved

#8 Allen Brown

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Posted 03 October 2006 - 21:40

The only thing I can think of in that time frame was Richardson's 1.4-litre (FV-based?) turbo but I very much doubt that would have been 2 stroke. Sorry, I'll go away as well...

#9 Allen Brown

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Posted 03 October 2006 - 21:45

Or ... Paul Emery? A f8 turbo based on a pair of Imp engines?

Wrong period - this lunacy was mid-1960s - but I'm getting closer.

#10 Bonde

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Posted 03 October 2006 - 22:58

David,

Two stroke turbocharged diesels are used routinely for very large marine engines, so at least it works for very large, slow-revving, long-stroke engines running at more or less constant revs.

Wasn't the (Australian, IIRC) Orbital engine also a turbocharged two-stroke? I'll need to do a Google on that.

As for the engine concept I mentioned in my previous post, I'm getting more convinced now that I may be mixing memories of a number of different engines, not specifically any F1 turbocharged two-stroke.

I also recall something about a Husquarna two-stroke sometime in the mid to late 1970s, but IIRC that was for Formula 2. I think there was a small article and a photo of it installed in a March F2 chassis (782, IIRC) in Autosport.

Or maybe I'm just going senile... :

#11 Doug Nye

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Posted 03 October 2006 - 23:06

Bonde - at least I won't be alone then...

A British project - 1974-75ish... This isn't a wind-up, I'm as puzzled as anyone.

DCN

#12 RacingCompagniet

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Posted 04 October 2006 - 06:50

Originally posted by Bonde
David,


I also recall something about a Husquarna two-stroke sometime in the mid to late 1970s, but IIRC that was for Formula 2. I think there was a small article and a photo of it installed in a March F2 chassis (782, IIRC) in Autosport.

:



You are right about the Husqvarna-based F2 engine. Someone in Sweden got the idea of connecting five Husqvarna 400 cc two-stroke motocross engines by chain-drive and then installing it in March chassis. I don´t think they ever managed to get a functioning transmission, so it never ran.

#13 2F-001

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Posted 04 October 2006 - 06:55

Originally posted by David Beard
Has there ever been a turbocharged 2 stroke? I think not. Are you sure we shouldn't be talking about a supercharger...

There are examples of forced-induction 2-stroke diesels, I believe; are these always supercharged then David (eg: the Ecurie Ecosse transporter) rather than turbine-assisted?

#14 RTH

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Posted 04 October 2006 - 07:02

Originally posted by David Beard


Would a turbo 2 stroke actually work? Putting a turbine in the exhaust stream isn't exactly going to be of assistance to the extraction process, like an expansion chamber. Has there ever been a turbocharged 2 stroke? I think not.


My thoughts as well David.

What has prompted this question Doug, has someone definitely said this was tested are there any more fragments of information to go on ?

#15 Doug Nye

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Posted 04 October 2006 - 07:34

Fragmentary recollection by a friend of a once celebrated pre-war engineer, now long-since deceased. This would have been a project in the twilight of his career. I don't want to offer too much since I'm seeking genuine recollection. If anyone should emerge with a jigsaw piece which fits the two others we now have, then we'd be 'off to the races'. I hope this makes a whacky kind of sense? I just don't want to prompt falsehoods. But I do want to get to the bottom of the story - is it fact, or fable?

DCN

#16 Sharman

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Posted 04 October 2006 - 10:26

Bedford produced a 2 stroke turbo diesel in the 60s for use in coaches and trucks, can't recall details but I travelled in one, a coach I mean, many times on the way to away rugby fixtures (which probably explains why I can't remember details)

#17 gary76

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Posted 04 October 2006 - 12:07

Three two-stroke cycle engines I recall:
1) The Treen 'Excalibur' X configuation proposal about 1968
2) A turbocharged 750cc opposed piston engine proposal by some students at Cambridge University about 1958.
3) Phil Vincent (of Vincent Motorcyle fame) was involved with a novel two-stroke cycle engine in the 1970's. Also Phil Irving made some racing car engine proposals about the same period but I can find no trace of them or recall whether or not they turned into 'metal'!
Maybe somebody will remember.
Also at the risk of opening this discussion to a much wider field: the two-stroke cycle engine responds extremely well to the application of turbocharging, recall the Foden Mk7 truck engine and several others.
Gary

#18 Allan Lupton

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Posted 04 October 2006 - 12:12

Originally posted by David Beard


Would a turbo 2 stroke actually work? Putting a turbine in the exhaust stream isn't exactly going to be of assistance to the extraction process, like an expansion chamber. Has there ever been a turbocharged 2 stroke? I think not.


Don't forget that not all two-strokes are the Day-cycle as in strimmers and BSA Bantams! Anyway, they require some back-pressure to work properly.

A twin-piston two-stroke (other than the Trojan) requires external pumping of some sort, and in the case of the Vintage Fiat racing engine, the Commer TS series and many others, a roots blower was used. A turbocharger can easily provide that pumping. As this isn't the technical forum, I won't provide the full explanation. :D

#19 David Beard

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Posted 04 October 2006 - 12:48

Originally posted by Allan Lupton


As this isn't the technical forum, I won't provide the full explanation. :D


But please do...I'm sure those that aren't interested won't read this thread anyway.

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#20 ace woodington

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Posted 04 October 2006 - 14:27

I recall something about a two stroke F1 engine. I think it was only a theory by Paul Emery????

I will do some more research but I feel it was first muted in the mid to late 60's

ace

#21 Bonde

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Posted 04 October 2006 - 14:28

Apologies to Doug about the derailing - but it seems to me the Orbital engine wasn't turbocharged after all, but supercharged.

Then there was the incredibly complex Napier Nomad two-stroke forced induction piston-cum-turbine diesel aviation engine which had an exhaust blown turbine and compressor arrangement which was also separately fueled (apart from residual exhaust flow from the piston portion of the engine), as well as being geared to the crankshaft...A fascinating compound engine.

I'll only post again in this thread if I have anything to contribute to Doug's opening post request - which I very much doubt will happen, I'm afraid.

#22 Stoatspeed

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Posted 04 October 2006 - 15:22

Maybe not that helpful, but I have a nagging memory of something like this being on ACBC's agenda shortly after the turbine experiments. Certainly Lotus was getting to the point in the mid-70s where they might have tried engineering such a concept.

From my time at Lotus, I don't recall seeing or hearing any war stories, but the "museum" area did have a few rather odd-looking piles of engine parts (including the complete 1.5 litre F1 turbo engine funded by Toyota during their time of part-ownership of the firm). Lotus also certainly dabbled with 2-strokes many times later than the period of DCN's query, and were involved with some vehicle adaptation work for Orbital under my watch .... but that's another tale!

However, with Doug's Hethel connections, I am sure this is a line he's already excluded, so I'll stop rambling!

Dave

#23 f1steveuk

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Posted 04 October 2006 - 16:22

Amherst Villiers once mentioned two projects to me. One was a development of a Percy Bradshaw engine called I think, the "Omega", a strande sort circular piston thingy. The other was a two stroke, turbo F1 engine, based loosely on the opposed cylinder arrangement of a Commer commercial engine of opposed pistons. From my addled brain I recall a flat six with a turbo mounted on top. I return home to France tomorrow, so I'll look in my papers

#24 ghinzani

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Posted 04 October 2006 - 18:44

Originally posted by f1steveuk
The other was a two stroke, turbo F1 engine, based loosely on the opposed cylinder arrangement of a Commer commercial engine of opposed pistons.


I hope it was'nt the same size as the Commer TS3, the front wheels would never have touched the ground! As mentioned previously Foden also produced a Turbo 2 stroke diesel, as did Detroit Diesel which may or may not have been the engine in the Bedford bus, given they were all part of GM. The Commer and the Foden are two of my faveourite sounding engines of all time, the follow on TS4 could have been a world beater but like so many British products of the time it was scrapped (as I recall at the behest of Cummins who had signed an engine deal with Rootes/Dodge/Karrier).

This mystery engine sounds very intrigueing anyway, a two stroke F1 - when were the rules changed to forbid such a thing? Imagine the pollution!

Also Stoatspeed what more can you tell us about the Toyota F1 engine that Lotus recieved - any dates, did it run etc?

#25 David Beard

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Posted 04 October 2006 - 18:49

Originally posted by David Beard


Would a turbo 2 stroke actually work? Putting a turbine in the exhaust stream isn't exactly going to be of assistance to the extraction process, like an expansion chamber. Has there ever been a turbocharged 2 stroke? I think not.


OK then, Beard. What about this turbo conversion kit for a 2 stroke snowmobile??

http://www.benderrac...roductTypeID=15

It seems to be possible..... :

#26 ghinzani

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Posted 04 October 2006 - 18:55

Originally posted by David Beard


OK then, Beard. What about this turbo conversion kit for a 2 stroke snowmobile??

http://www.benderrac...roductTypeID=15

It seems to be possible..... :


Thats the sort of post we like, argueing with yourself!! :clap:

#27 Stoatspeed

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Posted 04 October 2006 - 20:11

Originally posted by ghinzani
Also Stoatspeed what more can you tell us about the Toyota F1 engine that Lotus recieved - any dates, did it run etc?

Apologies for drifting off-topic, but I'll answer this!

Alas, ghinzani, I can't tell you much ... the engine was apparently designed and built by Lotus(Tony Rudd was still in charge at the time ... I've never read his book, is it in there?) for their Japanese "partners" and the display engine seemed to be an (externally) complete engine with turbos and ancillaries. However, I do not know if it ever ran (dyno or car). In this period, Lotus was running Renault and Honda turbos in F1, but I am sure that Toyota planned to take over Ketteringham Hall if it pleased them!That puts the date somewhere in the 1984 to 1987 range.

During my tenure (94/95), the "museum" was basically a corner of one of the workshops with a few interesting cars and engines lying there - we would proudly walk visitors through the derelict engineering artifacts and reel off half-known facts to impress them! I don't think there were any factual info panels there at all.
For a long time, the Etna and M200 concept cars were there, together with a Cortina (ACBC's own?), Elan, Carlton, assorted James Bond memorabilia .... The other engines included the V12 Lotus built for Cadillac (origianlly shown in the 1988 Voyage show car) and the modular air-cooled boxer light aircraft engine which was one of ACBC's last pet projects before he "died" ;) (prop driven from the camshaft to get 2:1 reduction :eek: ). It was more of a graveyard at the time, but I have heard that it has now been organized into a real museum as part of the revamp of the Hethel buildings - has anyone got knowledge of this?

Anyway, let's get back on topic and see if we can help Doug ...

Dave

#28 Doug Nye

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Posted 05 October 2006 - 11:47

No, no Dave - these digressions are far more interesting. :cat:

DCN

#29 Stoatspeed

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Posted 05 October 2006 - 13:30

Much obliged, Sir Doug!
... so while we are so far off topic, do you have any inside scoop on the mystery of the embryonic early 80s Toyota/Lotus engine, since you have had the honor of being acquainted with the principal suspects?

#30 Doug Nye

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Posted 05 October 2006 - 16:52

Yes, somewhere I have pretty much chapter and verse on that Toyota turbo engine. Tony Rudd was terribly proud of it, and described it as the 1500 horsepower engine and believed it should have beaten everything.

DCN

#31 T54

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Posted 05 October 2006 - 19:37

Doug,
Giancarlo Morbidelli built but I believe never completed a V6 2-liter 2-stroke for his buddies at Ferrari for F2 use, I was told. This incomplete engine is on display in the Mordidelli museum in Pesaro. I saw the engine in 1989 and it had rotary induction, seghmented exhaust valves on top of the combustion chambers run by belts. Very inventive, but F2 died too soon to be replaced by F3000.
Hope that helps... ?
Regards,

T54 :wave:

#32 Stoatspeed

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Posted 05 October 2006 - 21:07

Originally posted by Doug Nye
Yes, somewhere I have pretty much chapter and verse on that Toyota turbo engine. Tony Rudd was terribly proud of it, and described it as the 1500 horsepower engine and believed it should have beaten everything.

DCN


Published? If not, are there plans? If Tony claimed horsepower is even close, then it would have been a winner (in the right chassis!), but maybe they were "Bourne Horse Power" units -- not quite available YET, but they'll be along any race now!! Unless, of course, the Nye files contain dyno test data ... tease us some more, Doug!

#33 ace woodington

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Posted 07 October 2006 - 13:02

I knew I had heard of this idea somewhere!

Goto www.forix.com/8w/emspec.html

It is mentioned as an idea. I was working for a short time for Jeremy Delmar Morgan who drove with Paul in am Imp at some continental races in the 60's, and I am sure the idea was discussed at that time. Ace

#34 Stoatspeed

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Posted 09 October 2006 - 15:25

See, I knew ACBC was involved somewhere! :cool: (even if he's only mentioned on the same page in a totally removed context ... : ).
Sounds like we need a Paul Emery expert to dig for the truth here ... or was this a different project from the one Doug is chasing? Allen picked up the Emery Imp theory in post #9, but we passed over it quickly ... any more to add, Allen?
Dave

#35 allen1942

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Posted 16 May 2013 - 08:45

Much obliged, Sir Doug!
... so while we are so far off topic, do you have any inside scoop on the mystery of the embryonic early 80s Toyota/Lotus engine, since you have had the honor of being acquainted with the principal suspects?

Can I join in albeit late in the day, I worked at Lotus for six months as a specialist engineer on that V6 turbo over the winter of 1983 - 1984. The design was a fairly conventional V6 twin turbo, but the turbos were smaller and a twin spool, axial flow, engine driven supercharger fed them, in an attempt to eliminate turbo lag, my part being the supercharger. Unfortunately, due to other work commitments, I left before the project was completed, so didn't see the engine run, and as Lotus continued with the Renault engine, I can only assume that there were too many problems for it to be a success.

#36 Garsted

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Posted 16 May 2013 - 18:33

There are examples of forced-induction 2-stroke diesels, I believe; are these always supercharged then David (eg: the Ecurie Ecosse transporter) rather than turbine-assisted?

The Napier Deltics were supercharged two strokes (one model was turbocharged), and more recently the Wilksch Airmotive light aircraft engine http://wilksch.net/ is one such, turbocharged when in flight, but with a supercharger for starting.

Doesn't help Mr Nye with his question though.

Steve

#37 arttidesco

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Posted 16 May 2013 - 21:05

Some more details on the 2 stroke turbocharged flat six on the eighth post of this thread, hope you speak good French is good Doug :drunk:

#38 Spa65

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Posted 17 May 2013 - 18:11

I remember reading about this at the time. Whether it was in one of the motoring magazines, or some conjecture in a newspaper, I have forgotten. However I distinctly remember the proposition that Ferrari were looking at the possibility of a 1.5 litre supercharged two stroke engine (or perhaps turbocharged - can't remember) as a formula one engine.

My limited knowledge of engine design has never stopped me speculating over the years about this, though I never heard about it again until now. My naive thoughts were that a conventional two stroke should be able to extract more power for the same size of engine compared to a four stroke, though at a considerably increased fuel burn. (I had a three cylinder Suzuki GT380 motorbike that got 36mpg at 65 mph - my diesel Corsa gets nearly double that.)

So why did no-one try using a 3 litre two stroke, normally aspirated engine in F1?

#39 Spa65

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Posted 17 May 2013 - 18:23

So why did no-one try using a 3 litre two stroke, normally aspirated engine in F1?

Oops. Should have read Arttidesco's link before replying.

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#40 f1steveuk

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Posted 17 May 2013 - 18:47

I am sure Paul will be along soon to wrap this one up, and I don't want to steal his thunder

http://www.amazon.co...mherst villiers

and he tells the story better than I do!!

#41 scolbourne

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Posted 11 December 2013 - 13:55

http://www.elsberg-t...ecordbikes.html

 

This link shows a turbo-charged two stroke  50cc engine so it obviously does work.

 

 

"Enter John Buddenbaums Minarelli AM6 powered streamliner!
John Buddenbaum has set his sight on the 50cc topspeed record and broke it big time !
With current setup, a turbocharged AM6 engine fed by methanol, the Buddfab streamliner
managed a speed of 233,3km/h!"

 

N.B. a two stroke engine can be made super-charged by simply designing the case correctly as the bottom of the piston compresses the mixture in the lower engine.



#42 ray b

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Posted 11 December 2013 - 15:26

for my dad's gadabout car he proposed

''The two-cycle, air-cooled engine with direct fuel injection and turbocharger would have been mounted either in front or in back at the owner’s discretion.''

that was mid 40's

sadly the project never got beyond the first car with a MG frame and motor

 

but the idea of a turbo 2 stroke has been around a while

 

http://blog.hemmings...hantom-corsair/


Edited by ray b, 11 December 2013 - 15:55.


#43 Hawkeye

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Posted 11 December 2013 - 17:05

I'm in the throes of re-reading old 'Motorsport' mags and think that I saw some reference to Ginetta (of all people) toying with a radical engine development - I can't now locate the relevant text unfortunately............................



#44 BRG

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Posted 11 December 2013 - 19:40

I'm in the throes of re-reading old 'Motorsport' mags and think that I saw some reference to Ginetta (of all people) toying with a radical engine development - I can't now locate the relevant text unfortunately............................

Taken from the thread "Quirkiest F1 Engine Concepts" post by Tim Murray.

 

Here's the story as told by Bob Walklett in Ginetta: The Inside Story:

 

 

I thought I was immune to surprises but I was always wary when Trevers would come into my office with a little grin on his face. 'What do you say we build a Formula 1 engine, Bob?' he said. 'I don't really think I am in the mood for jokes, Trev,'I replied. 'It isn't a joke,' he said: 'Ivor and I have worked out a design which is perfectly feasible. It is a 1½-litre 2-stroke engine. Current F1 rules allow for 3-litre naturally aspirated or 1½-litre blown. We could make it in-house: we have the mills, the lathes, the borers. We can turn up our own steel cranks and make the engine patterns.'

 

I suppose incredulity was written all over my face.

 

'Would you like to see the drawings?' he said. ‘I would love to see the drawings,' I replied. 'Right - I will go and get them.' I cleared a space on my desk in anticipation and Trevers laid them before me. I could see straight away that it was twelve cylinder, horizontally opposed, two crankshafts with a central drive. 'Perhaps you will explain it further,' I said, 'where are the inlet and exhaust valves? Where is the induction manifold? Where is the valve gear?' 'It doesn't have any! It is based on piston-controlled inlet and exhaust ports. Let me show you how it works.' I was intrigued. 'But there only seems to be about 50 mil throw on the cranks,' I said. 'That's right, the pistons will move about 100 mil and we shall have six firing strokes for one turn of the crank.' 'More like a turbine,' I said. 'Well, similar: we shall turbocharge it. Do you like it?' 'I think it's fantastic, but we can't possibly make it!' I answered. 'You may well be right, Bob, but do you agree we have a go, in between times, for a little light relief.' 'Light relief! You call that light relief!' I exclaimed, to which Trevers responded: 'Well, I can have a play in the evenings can't I?'

 

I was totally fascinated to watch it develop. Trevers made the patterns for the crankcase and had them cast in aluminium alloy. The steel cylinders were next. These had to be made with a special steel. When the supplier quoted, I said: 'That's reasonable for a foot.' 'The price I've given you is for one inch,' he said.

 

Obviously, it was a part-time, general-interest project and it was overtaken by other events. I don't suppose any of us expected it to be finally finished, but as an exercise in original thought and the sheer gutsiness to have a go in-house, it reflected perhaps what Ginetta was about: we were always prepared to go as far as we could - and then perhaps even a little further.


Edited by BRG, 11 December 2013 - 19:42.


#45 Rudernst

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Posted 11 December 2013 - 23:55

weeeell

 

I just have to get this out.....

 

In a two stroke engine the incoming fresh charge expells the spent/burnt charge.

biggest problem in a two stroke is the mixing of fresh and burnt gas during this process 

generally turbocharging a two stroke does not make sense because You just directly push the fresh intake charge out of the open exhaust

 

this is different in a Diesel (or a modern direct injection Otto for that matter) engine because they just draw in pure air

(which You can afford to lose partly out of the exhaust)

and inject fuel direct into the cylinder AFTER the exhaust port has closed

this explains why superchareged DIESEL engines were a commercial success.

DIESELS, but no petrol burners !!!!

btw most large sea going vessels are powered by two stroke turbocharged Diesels, nowadays

 

East German Walter Kaaden developed the so called expansion chamber exhaust,

what a stroke of genius !!!!

this is basically a trick to use reflected soundwaves to draw intake charge as far as the exhaust header and then push

it back into the cylinder before the exhaust port closes

this is a simple effective, no downside, no power sapping way of supercharging a two stroke without mechanical moving parts

just using a funny shaped bulbous exhaust

 

from the time of Kaadens invention in the very early 1960ies, soon ripped off by the Japanese with the aid of East German fugitive and later world Champion Ernst Degner, two strokes killed 4 strokes in bike racing

enjoying a 33 % power Advantage

Explanation:

you get twice as many power strokes in a two stroke compared to 4 strokes at 2/3rds efficiency = 4/3rds 

resulting in 1/3 = 33 % power advantage

this started out with the very small engines of 125 and 250 cc and slowly worked its was up the racing bike class system

reason behind that is that the smaller the cylinder the easier the scavenge process is

meaning that you can avoid unwanted mixing of fresh and burnt gas

over time, think 10 years, bike engineers learnt to apply this to ever larger engines

as more and more internal engine gas turbulence theory was understood

in 1974 a Yamaha stroke 500 cc bike beat the 4 stroke MV Agusta 500 cc bike for the first time to take the championship

and from then on until the banning of two strokes from they simply won EVERY motorbike road racing championship

 

a little later in the 1970ies,

looking at larger Motocross race bike engines You could see that 360 cc single cylinder two strokes wiped the floor with 500 cc four strokes

giving more power than actually needed

now 8 times 375 cc would have made 3 litres as per F1 limit

or go for 12 times 250 cc to arrive at 3 litres at 40 to 50 hp per pot = up to 600 BHP, goodbye DFV and Ferrari

(I kid You not, even the ROAD LEGAL fully silenced Maico 250 cc single gave 30 hp in 1978, ROAD LEGAL !!! and good for 25.000 km)

you could see that over the counter Motocross technology would yield much more power than a DFV

properly developed and IN THE LONG RUN

think 20-30 % more power at 20 % less engine weight

as had happend in racing bikes

just doing the math from what Your cheap 4.000 US-Dollar 360-400 cc Maico or KTM or YamaZuki MX bike

would  do on the rolling road round the corner

 

soon afterwards two strokes were banned in F1

call me cynic but i dont think that was pure coincidence

 

two strokes were allowed in F1 as long as they were considered smoky, nasty  and gutless

by the time they had taught Honda 4 strokes a killing lesson and forced them out of bike racing

they were banned in F1 car racing, just as a precaution.....

 

Rudolf


Edited by Rudernst, 13 December 2013 - 20:52.


#46 Ristin

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Posted 13 December 2013 - 10:05

Just to set the record straight: Mr. Kaaden is widely known as Walter, not Achim

#47 Rudernst

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Posted 13 December 2013 - 14:29

you are right

I was too reliant on my ageing memory

 

thanx for the remark

 

Rudolf



#48 Sisyphus

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Posted 13 December 2013 - 20:06

weeeell

 

I just have to get this out.....

 

In a two stroke engine the incoming fresh charge expells the spent/burnt charge.

biggest problem in a two stroke is the mixing of fresh and burnt gas during this process 

generally turbocharging a two stroke does not make sense because You just directly push the fresh intake charge out of the open exhaust

 

ONLY FOOLS (and Brits) would turbocharge a two stroke unless its direct injection

 

 

 

 

Not true, Rudolf.  Two strokes without direct injection have been successfully turbocharged because you are forgetting about the backpressure from the turbocharger turbine. 

 

With a mechanical supercharger, you do have the problem of pushing the intake charge out the exhaust but with a turbo, you can manage the delta pressure across the engine with the turbine backpressure and reach an acceptable result. 

 

Your bigger problem would be to avoid melting down your two stroke if its air cooled due to the much higher power density when you turbo it.


Edited by Sisyphus, 13 December 2013 - 20:07.


#49 Rudernst

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Posted 13 December 2013 - 20:52

well

hmmm

 

yes, sure, you can play with the turbo backpressure

that did not occur to me

that will probably be tricky to set up to work over rev range and waste gate opening

 

and You have the added advantage of an unpressurised crankcase

allowing pressure fed lubrication, plain bearings instead of roller bearings

getting rid of built up cranks 

 

I would never dream of doing that aircooled..

 

Rudolf


Edited by Rudernst, 13 December 2013 - 20:54.


#50 Rudernst

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Posted 13 December 2013 - 21:09

come to think of it

 

how would one define

 

"successfully supercharged"

or

"successfully turbocharged"

 

??

 

DKW motorbikes won the 1938 and 1939 European 250 cc title,

being two stroke supercharged

(by a pumping piston, added to the crankcase)

that is tangible success, no doubt

but with hindsight the design was shown up as a development blind alley

fiendishly complicated for a two stroke and really drinking fuel

 

or is a nondestructive dyno run allready a success ?

 

Rudolf


Edited by Rudernst, 13 December 2013 - 21:11.