129 replies to this topic

[Roger Clark]

Are you trying to wind us up Roger ? The FWMV had cylinders each of 187.5cc.

AAGR

Not really, but I can't understand why 6s, 8s and 12s were so much better than the FPF if 350cc is the optimum cylinder size.

[D-Type]

I hadn't heard of Pomeroy saying that 350cc was the optimum cylinder size but before 1914 when h was most active, the majority of racing cars had cylinders very much larger than that. After the war, during which the advantages of an 8-cylinder engine had been learned, the competitive cars of the 3litre 1921 Grand Prix formula did have cylinders close to that size. Fiat's engine for the first year of the 2-litre formula was a six and therefore very close as was the 1923 Sunbeam which had certain similarities. After that, the 8-cylinder engine became dominant for the next 60 years; superchargers may have affected any calculations for a lot of that time.

I thought I'd read it was Pomeroy - it certainly pre-dates Duckworth

Not really, but I can't understand why 6s, 8s and 12s were so much better than the FPF if 350cc is the optimum cylinder size.

And the FVA of a few years later seems to have been better than all the 6s, 8s and 12s - or was F2 at the time limited to 4 cylinders?

[AAGR]

I thought I'd read it was Pomeroy - it certainly pre-dates Duckworth


And the FVA of a few years later seems to have been better than all the 6s, 8s and 12s - or was F2 at the time limited to 4 cylinders?

No - Ferrari used the Dino V6 engine in F2, which is one reason why the Fiat Dino was put on sale ....

[arttidesco]

Micheal Olivers book on the Lotus 49 throws some interesting light on the short comings of the Weslake V12, he quotes Dan Gurney

"By dint of tenacity and excellence they (Weslake) were making a competitive engine with old fashioned machinery. In fact, the cylinder block was made on some old Royal Navy World War 1 machinery that was purchased almost as scrap, and which was turned into something that had weight and the rigidity so that they could make accurate machinings !"

"We had lots of passion but not much money."

Dan also points out that the DFV had a superior oil scavenge system, which I presume enhanced it's reliability over the Weslake.

[Charlieman]

I seem to recall that Duckworth calculated that 350cc was the optimum size for a four-stroke cylinder. The 8 cylinders of the DFV were 375cc, which is close enough!

I always thought that the idea came from Harry Ricardo. I'd like to know the origin.

Note also that the proposition is about relatively short stroke cylinders in an automobile engine; the rule of thumb accounts for area (square-ish factors: heat loss, friction) and volume (cube-ish factors: properties of expanding fuel mixture). For a tiddly bike engine or a monster boat, the optimum size is completely different.

[Henri Greuter]

Not really, but I can't understand why 6s, 8s and 12s were so much better than the FPF if 350cc is the optimum cylinder size.

Valve area and valve activation, bore and stroke ratio perhaps?

I know, F1, F2 etc are something entirely different the Indy but I read about Ferrari's onslaught at Indy in 1952 with their V12 that was deemed to be superior to the old Offy engine except in one, vital value: Torque. Torque that the shortstroke Ferrari V12 lacked but the old longstroke fourbanger had in spades. So when coming out of the turns the Offy powered brigade passed the Ferrari's on sheer acceleration and reached their top speed much faster. Topspeeds were about comparable for the cars but the offy cars reached it quicker.

If other specifications are (far) less than ideal.... for example: even if you have the "ideal 350 cc" per cylinder, when you only have a twovalve pushrod operated head on it.....


henri

[Roger Clark]

Valve area and valve activation, bore and stroke ratio perhaps?

I know, F1, F2 etc are something entirely different the Indy but I read about Ferrari's onslaught at Indy in 1952 with their V12 that was deemed to be superior to the old Offy engine except in one, vital value: Torque. Torque that the shortstroke Ferrari V12 lacked but the old longstroke fourbanger had in spades. So when coming out of the turns the Offy powered brigade passed the Ferrari's on sheer acceleration and reached their top speed much faster. Topspeeds were about comparable for the cars but the offy cars reached it quicker.

If other specifications are (far) less than ideal.... for example: even if you have the "ideal 350 cc" per cylinder, when you only have a twovalve pushrod operated head on it.....


henri

But the Ferrari came from a road racing background where power at low engine speeds was more important than at Indianapolis. Nobody, as far as I can remember, seriously considered a 4-cylinder 4.5-litre Grand Prix engine. Not since 1914 anyway.

[Henri Greuter]

But the Ferrari came from a road racing background where power at low engine speeds was more important than at Indianapolis. Nobody, as far as I can remember, seriously considered a 4-cylinder 4.5-litre Grand Prix engine. Not since 1914 anyway.

I used the Ferrari as an example to answer the question on why the FPF despite its ideal 350 cc cylinder capacity was beaten.
My answers suggests as if the Ferrai had two valves pushrod operated but in fact it had a SOHC.

But I wondered if the FPF perhaps had disadvantages like a less than optimal valve size, valve activation, bore vs stroke ratio.

You're right regarding a 4.5 liter GP engine. No postwar car would be fitted with a fourbanger. Though I wonder if a Talbot had been fitted with an Offy, how would it have done?
The Talbot had a 6 but two valves and either a single cam and perhaps even only pushrods operating them. The Offy had DOHC and 4 valves per cylinder. Another case of and engine with a distinct disadvantage in numbers of cylinders but making up with more modern technology details.


The most modern kind of engine I can think of that comes close to a 4.5 liter 4 would be the rumored Ferrari 2.5 liter twocylinder. Never saw pictures of it but that must have bveen something!


Hope this straightens a few things out?


Henri

[D-Type]

How much did Ferrari manage to stretch the 3-litre 750 Monza engine? I know they produced the 3.3 litre 825, still along way short of 4.2 or 4.5 litres, but did they or anyone else successfully stretch it further?

[AAGR]

How much did Ferrari manage to stretch the 3-litre 750 Monza engine? I know they produced the 3.3 litre 825, still along way short of 4.2 or 4.5 litres, but did they or anyone else successfully stretch it further?

According to the famous Tanner/Nye tome, the 860 Monza had a 3.4-litre derivative of the same engine, but then of course my interpretation could be quite wrong....

[Spaceframe]

One point not yet addressed is whether the 3-litre formula would actually have continued, at least in the form that then existed. Without the DFV, would there have been the forcing house which drove the development of (especially) the BRM V12 and Matra V12? Even in 1969-70, with the DFV around, the early F5000s were approaching the speeds of F1 cars - without the DFV they might have exceeded them.

So, without the DFV, might the F1 capacity limit have risen? To 4.2 litres maybe? A true world formula for the first time since the 40s?

The three-liter formula was to expire at the end of 1970, so the garagistas would've had something like three seasons to find a reliable engine-supplier.

The final years of the 1,5 liter formula was seeing the rise of the kit cars - BRM, Ferrari and Honda made everything in-house, but everybody else relied on custom engines from Climax and BRM, so the situation was new, only the solutions available.

Which leads me to conclude that BRM would've been happy to sell V12s to customers, but the most popular choice among the kit car entrants would most likely have been the Repco. I can easily imagine Jack Brabham becoming a partner in such an enterprise, and I suspect it would've been quite profitable, both from a sporting and an economic point of view.

If so, no need for another formula after 1970.

If, however, neither Repco nor BRM engines had become generally available during 1968, I'm pretty sure the FIA would've considered another engine formula. Either a stop gap de facto F2, or - to my mind more likely - a formula very close to or identical with Indy. After all Eagle and Lotus were regulars at the Brickyard in those days and there'd been a steady stream of US drivers competing regularly in F1 since the late 1950s, so it might make sense to have one common formula, uniting European and US racing at the top level for the first time since (if my memory doesn't fail me) 1921.

[Bob Riebe]

IF Ford had not put its sources and money behind Cosworth another thing to consider is what would have happened at Indy.

No Ford Cosworth DFX.

Even though Henry Ford II had a snit fit with the Cosworth and racing at Indy in the seventies, had Ford not put it money to behind Cosworth they probably never would have ever had a link to go there.

Edited by Bob Riebe, 11 September 2012 - 18:52.

[D-Type]

Sorry to go OT. Was the DFX branded as "Ford" like the DFV or was it branded as "Cosworth"? ie what name was on the cam covers?

[Bob Riebe]

It was Ford until Henry told them to get the name Ford off, he caved to the Jack-asses in Washington with their attacks against Detroit in the late sixties early seventies.
It then could be Ford again when level heads again ran Ford. Especially after Ford took total control of Cosworth.

[arttidesco]

Sorry to go OT. Was the DFX branded as "Ford" like the DFV or was it branded as "Cosworth"? ie what name was on the cam covers?

I always understood the DFX initially a Parnelli Jones endeavor, before Cosworth took on a similar project with Cosworth cam covers.

IIRC Cosworth cam covers were also used by Saudia sponsored Williams on his DFV's because of the Escort CKD deal between Ford and Israel.

Cue a photo of a DFX with Ford cam covers !

[D-Type]

I always understood the DFX initially a Parnelli Jones endeavor, before Cosworth took on a similar project with Cosworth cam covers.

IIRC Cosworth cam covers were also used by Saudia sponsored Williams on his DFV's because of the Escort CKD deal between Ford and Israel.

Cue a photo of a DFX with Ford cam covers !

But only until Ford noticed!

[arttidesco]

But only until Ford noticed!

I had no idea they ever did

[arttidesco]

Which leads me to conclude that BRM would've been happy to sell V12s to customers, but the most popular choice among the kit car entrants would most likely have been the Repco. I can easily imagine Jack Brabham becoming a partner in such an enterprise, and I suspect it would've been quite profitable, both from a sporting and an economic point of view.

Would Repco have had the capacity to supply say three team's ?

[Glengavel]

I always understood the DFX initially a Parnelli Jones endeavor, before Cosworth took on a similar project with Cosworth cam covers.

IIRC Cosworth cam covers were also used by Saudia sponsored Williams on his DFV's because of the Escort CKD deal between Ford and Israel.

Cue a photo of a DFX with Ford cam covers !

I thought it was because Williams had Leyland sponsorship - at least, that's how it was according to Autocar.

[Tim Murray]

Leyland didn't start sponsoring Williams until 1980. They were using the Cosworth cam covers well before that, for the reason given by Arttidesco, and because of Henry Ford II's publicly-expressed support for Israel.

Edited by Tim Murray, 11 September 2012 - 21:28.

[Ray Bell]

Originally posted by arttidesco
Would Repco have had the capacity to supply say three team's?

Repco, overall, were a huge organisation...

The Repco-Brabham side was small, but it was inventive and energetic. They were in 1967 supplying and maintaining engines for Brabham's F1 and Tasman efforts, for Scuderia Veloce, Leo Geoghegan and John Harvey's Gold Star cars as well as sports car engines for Bob Jane Racing Team. By the end of the year they had the following projects on the go:

1. Quad cam engines for F1.

2. Providing Frank Matich with a sports car engine as well as developing a quad-cam 5-litre engine for Can-Am use.

3. Developing an Indianapolis engine (a spin-off from the sports cars stuff, or vice versa?).

4. Trying to work out why Leo Geoghegan was having so many problems make the Repco V8 work in his Lotus 39*.

That is not the work of just one or two men, the manpower was delegated as was necessary from within the Repco organisation. Had there been no Cosworth V8 and they had overcome the lubrication problems** to be experienced by Jack and Jacky Ickx during 1968, I'm quite sure the Repco organisation could have entertained the thought of supplying two or three paying teams with F1 engines that would have been more than just competitive.

Repco were at that time expanding their international market, it would have made sense (if the opportunity was there due to the lack of other commerically available engines) to become a major engine supplier to F1.

* The 2.5 version of the Repco V8 had some inherent problems because of its short stroke and extreme stroke/rod length ratio. It ran 56° of advance to achieve its power because of the lengthy dwell period. The problems Leo Geoghegan experienced led him to put the Climax engine back in his car until they solved them, so Repco would have been very busy with these issues during 1967 and they gave him a new engine in 1968 to overcome it.

** Phil Irving has suggested that the engine required two completely separate oiling systems with different grades or types of oil for the valvegear and the bottom end. I would suggest that Jack pulled the pin on Repco, perhaps with assistance from Ford (he was to open a Ford dealership in Sydney shortly after this), and that this was the reason for Repco scaling back their efforts more than anything else. But he was tired of the unreliability problems with the 4-cam engine in 1968. The other suggestion that has been made is that the dyno testing etc was done with complete reliability using Ampol oils in Australia, Jack ran Gulf in F1. All other 4-cam engines had no similar problems.

[Tim Murray]

But he was tired of the unreliability problems with the 4-cam engine in 1968. The other suggestion that has been made is that the dyno testing etc was done with complete reliability using Ampol oils in Australia, Jack ran Gulf in F1. All other 4-cam engines had no similar problems.

I've often wondered what might have happened if that engine had been a bit more reliable. The car was obviously quick going by by the qualifying times, including Rindt's two poles. A few wins would not have been out of the question. Rindt might have stayed for '69, and a few teams might have been knocking on Repco's door looking for engines.

[Ray Bell]

Absolutely...

And those engines, the 4-cammers, were dutifully reliable in every other sphere. Matich never had problems, I think the Indy one stood up all right and subsequent users don't seem to complain.

[Catalina Park]

Had there been no Cosworth V8 and they had overcome the lubrication problems** to be experienced by Jack and Jacky Ickx during 1968...

** Phil Irving has suggested that the engine required two completely separate oiling systems with different grades or types of oil for the valvegear and the bottom end. I would suggest that Jack pulled the pin on Repco, perhaps with assistance from Ford (he was to open a Ford dealership in Sydney shortly after this), and that this was the reason for Repco scaling back their efforts more than anything else. But he was tired of the unreliability problems with the 4-cam engine in 1968. The other suggestion that has been made is that the dyno testing etc was done with complete reliability using Ampol oils in Australia, Jack ran Gulf in F1. All other 4-cam engines had no similar problems.

It was't Ickx, it was Rindt.

I would go with John Judd's story. He says that it was a harmonic problem and not an oil problem. All the other 4 cam engines were different capacity and had different harmonics.

[Ray Bell]

You're right, it was Rindt!

And I'd also accept that there was a fair chance there were harmonics problems, these engines would have revved higher and had different harmonic moments to the bigger ones.

However, I was quoting Phil's views...

[xj13v12]

You're right, it was Rindt!

And I'd also accept that there was a fair chance there were harmonics problems, these engines would have revved higher and had different harmonic moments to the bigger ones.

However, I was quoting Phil's views...

Definately vibration causing valve insert/bucket issues. The DFV had the same issue but overcame it quickly and rather simply. Repco's people suspected what it was but were unable to engineer a fix in time to make a difference that year. This has been much quoted when Duckworth walked past the Brabham team guys and asked if they fixed the viration using x method. They said yes but to their chagrin the research and development had by now fallen behind. It can not be over emphasised how critical this issue was. The revs used in the 3 litre engine were quite a bit higher than the 4.2 Indy or 4.8 sports car version. The Indy car didn't have to run up and down through the critical range either.
I can dig out the technical description of this from one of the books but I was sure someone wrote it in this blog long ago. the bottom line is that the engine had the balls, the BT26 chassis had the goods (same car next season with the DFV) and the drivers were more than able to win. As always the history has been written and nothing will change it.

[Ray Bell]

Even with Phil dropping ash from his eternal cigarette down the intakes...

I think we have to accept that the crew at Repco did a fantastic job and deserve more credit than just to say, "They had an engine that was good enough when everyone else was floundering."

[arttidesco]

I think we have to accept that the crew at Repco did a fantastic job and deserve more credit than just to say, "They had an engine that was good enough when everyone else was floundering."

[xj13v12]

Yes I think that's the general feeling of the discussion. Repco were within a gnat's whisker of having 3 championships in a row and but for overcoming a technical issue and some timing with the arrival of the DFV, F1 records may well read very differently today.
Except that all such hypertheticals achieve nothing but we have fun discussing them.

[rl1856]

I am late to the thread but I'll reply anyway.

Absent a DFV, everyone else looks better. So to me, the most successful would have been those who were the best of the non DFV runners in 67-68. BRM, Weslake, Honda, Ferrari and of course Repco.

Would BRM have stayed with the H-16 ? It was certainly competitive in 67, and at times was the fastest behind the 49. It certainly needed more reliability. How much was the development of the V12 caused by the immediate success of the DFV ? If the V12 was still created as a sports car engine, then adapted for F1, I think it would have been moderately successful. It took 2 years of development, a house cleaning and Tony Southgate before the BRM V12 was successful.

Weslake. At the beginning of the season, Gurney could stay with the 49, and was consistently fast in their wake. But reliability and the inherent limitations of working with Weslake would have remained.

Honda? With Surtees behind the wheel the car was competitive in 67. Would the Hond-ola have been constructed ? Probably.

Ferrari? The loss of Bandini hurt and much of 67 was a development year for the team and Amon. They would have been ready to go in 68 and likely ran the table- especially if one JYS joined the team.

Matra? The V12 program would have been more successful, of that I have no doubt. Would Ken Tyrell and JYS partnered with them ? Who knows. What is known however is that Matra's F1 program greatly benefited from information received from Tyrell/Stewart. Absent that info, how would they have progressed ?

Repco. The 4 cam 68 car was a direct result of the DFV. Unfortunately it created problems they never could solve. Absent the DFV would they have further developed the 2 cam engine ? Would they have been in a position to supply other teams ? I think the answer to both questions is YES. They would have become the most effective competition to Ferrari in 68, but probably not winning the championship. Demand from other teams for Repco engines would have provided the capital to fund a manufacturing expansion sufficient to meet demand. Repco would have supplied engines to several teams, but probably not on the scale of Cosworth. Likely Repco customers would have been Lotus, McLaren and Walker. McLaren may have stayed with BRM for 68 however. Maybe one or 2 others....but absent an alternative engine would the one or 2 others even existed ?

Interesting "What Ifs" Would Climax have been convinced to develop the Godiva ? Maybe yes, maybe no. Would the engine have been competitive punched out to 3L, converted to gasoline and injection, and maybe 4 valve heads ? Who knows. More likely that they would have developed a new engine. But would they have even gotten involved ? Probably not, given the state of Jaguar in the late 60's-70's. I think we may have had turbo engines earlier than '77...possibly by 70 or 71.

69 Grid would have consisted of Repco Brabham / Ferrari / BRM / Matra / Mclaren / Walker / Lotus...or not much different than reality. Results would have Brabham and Ferrari fighting for the title, with occasional wins by the others.

Drivers benefiting: Ickx, Amon, Brabham, Rindt. Drivers most affected: JYS.

Just my thoughts.

Best,

Ross