Engine efficiency, now and then

[xpensive]

With the the advent of the new 100 kg/h ( 27.8 g/s) format from 2014, does anyone have an insight as to how much the overall efficiency of the F1-engine has improved its efficiency since the beginning of the modern-day 1966 3.0 liter formula?

Any numbers presented will be welcome.

[strad]

Cosworth DFV Engine Specifications: The Cosworth DFV is a 90° V8, 4-stroke cycle, DOHC 4-valve/cylinder, even-fire, water-cooled, gasoline fuelled, race engine designed to be a stressed member of the chassis. It has 3550 parts.

The Cosworth DFV (Dual Four Valve) V8 engine for Formula One ("F1") cars was based on the FVA (Four Valve series A) development motor which was based largely on the Ford Cortina road car engine (Kent) block for Formula Two racing. The FVA and DFV were developed under the same contract from Ford, which provided the financing. The DFV shares a number of internal sizes with the FVA, which was completed first and served as the 'proof of concept' of the DFV design.

Designer(s): primarily Keith Duckworth (1933-2005) of Cosworth Engineering in 1966/1967 under contract to the Ford Motor Company (Mike Costin and Keith Duckworth were the principals in the formation of Cosworth in London, England in 1958)
First production: 1967
First Race: Dutch Grand Prix, Zandvoort, Netherlands, June 4, 1967: two entered, finished 1st (Jim Clark), DNF (Graham Hill, who was on pole).
Last Race: still active in historic and vintage racing.
Capacity: 182.6 in3 / 2993cc (to meet the 3 litre displacement limit in Formula One implemented starting in 1966)
Power: 408 brake horsepower @ 9000 rpm (debut - 1967)
439 hp (1970)
450 hp @ 10500 rpm (minimum - 1973 spec.)

465 hp (1977)

Torque: 245 ft·lb @ 8500 rpm (minimum - 1973 spec.)





Crankcase:

Description: 90° V8 crankcase and cylinders cast together in aluminum. Wet cast iron cylinder liners sealed with O-rings. Steel, coated iron, and nikasil alloy liners were also tried. Nikasil alloy liners saved 8 lb in overall engine weight, and were standard by 1983.
Weight (with clutch): 370 lb / 168 kg
Overall width: 27.0" (686 mm)
Overall length: 21.5" (545 mm)
Bore: 3.373" / 85.674 mm
Stroke: 2.555" / 64.8 mm
Bore spacing: 4.100" / 104.1 mm
Deck height: 6.505" / 165.2 mm (crankshaft centerline to deck surface)
Crankshaft height: 5.23" / 132.8 mm (crankshaft centerline to external sump bottom)
Cylinder stagger: 0.375" / 9.5 mm (left ahead of right)
Materials: Cast aluminum block and head, forged steel crank and rods (earliest DFV cranks were billet), forged aluminum pistons, cast magnesium covers.
Firing order: 1-8-3-6-4-5-2-7
Compression ratio: 11.0:1 (approx.)
Fuel: 101 octane (M.M. - motor method) minimum
Rotation: clockwise when viewing front of engine
Mounting: At the rear end of the engine are suspension attachment points, and at the other are car attachment points at the top and bottom of the engine. The top chassis mounting bolts are part of the cam cover, and have 4 to 6 bolts per cover per end. The lower mounting bolts are part of a bracket bolted to the sump assembly. The lower bolts are located 9.0 inches (22.86 cm) apart. As the engine expands when it gets hot, the mountings are made so that the sheer forces are concentrated on the bottom bolts.
Serial numbers: The block serial numbers in the early years reflected the year the engine was built as the first digit, with two more numbers to indicated the unit number for that year. For example, DFV 701 was the first DFV built in 1967 and DFV 910 was the 10th DFV built in 1969. At a later date (likely circa. 1977 after 260 DFVs had been made) Cosworth went to sequential serial numbers; e.g. DFV 400 was the 400th DFV made (for Albert Obrist/Mario Hytten around 1986/87).
Crankshaft:

Description: single plane ("flat") common throw (2 rods per crank pin, no offset), forged nitrided steel (earliest cranks were billet steel), 5 main bearing crankshaft, hollow crank pins, weight 32 lbs / 14.5 kg, thrust taken on #3 main bearing, 8 bolts on flywheel flange.
Main journal diameter: 2.3755" to 2.3750" / 60.3 mm
Rod bearing diameter: 1.9370 to 1.9375" / 49.2 mm (same as Cosworth FVA: Bearing is Cosworth part number FA0067)
Connecting rod journal diameter: 1.9375" / 1.9370"
Crankshaft: End float: 0.004" / 0.009"
Connecting rod side clearance (big end): 0.006" / 0.012"

Piston :

Description: forged aluminum, 4 valve notches. Full floating wrist pin.
Piston compression height: 1.469 / 37.3 mm
Weight: ~328 grams (with rings, without pin)
Ring width:
top: 0.0315"/0.80 mm
middle: 0.0410"/1.04 mm
oil: 0.160"/4.06 mm
Piston ring gap (all rings): 0.017" to 0.022"

Connecting rod:

Description: forged steel, H-beam, fully machined connecting rods.
Bolts: 3/8" UNF
Connecting rod length: 5.23" (132.842 mm)
Wrist Pin length: 2.500" (63.5 mm)
Wrist pin diameter: 0.812" (20.638 mm)
Wrist pin end float: 0.000" ± 0.001" (retained by clips)
Rod/Stroke ratio: 2.05

Cylinder Heads:

Description: Cast aluminum, dual over head cams (DOHC), 4 valves/cylinder. Central spark plug in pent-roof combustion chamber. Each cylinder head has a stub shaft for cam drive gear on one end. The cylinder heads are interchangeable left and right.
Fastening: 18 retaining fasteners per head - 6 surrounding each cylinder - 10 studs from block, 8 studs from head.

[Greg Locock]

Presumably you are most interested in bsfc at full power. Good luck finding that.

[Tommy Cookers]

would there be data from endurance applications of F1 engines ?

Le Mans etc Prototypes had F1 engines from late 60s till ....... ??
(and the 2.1 litre forced induction equivalence allowance that led Renault to give us turbo F1)

the last F1 turbos (in their fuel limited 'economy' versions) vs the 3.5 litre 'NA opposition
(which were not required to be economical, but related to continuing endurance applications?)


BTW ...... this is all bound up with the modern era 4 narrow angle valve design that emerged contemperaneously from Weslake and Cosworth in 1966-7

has history a verdict on which of these should be credited with this gamechanging (re)invention ??
(I assume such a verdict has emerged by now)

[strad]

Just from shear longevity and acomplishment I would say the Cosworth...Wasn't the Weslake rather finicky?
My suspision lies in cylinder turbulence and filling where Cosworth had the upper hand.
I would agree with this quote

The performance of the Cosworth DFV was remarkable in 1967 when first raced yet, after 16
years of steady improvement, it was finally over 30% better in power/weight ratio and was
sold at 34% lower price in constant money terms (excluding VAT). It was a triumph of design
followed by a triumph of development, whose 154 Championship Grand Prix victories surely
will never be beaten.

Not only did Ford receive a magnificent bargain in advertising from its initial £100,000

(£1.5M at 2008 level) but so did the customers and Cosworth also profited.
The influence of the Cosworth FVA and DFV engines has spread far and wide since their
racing days, not only in racing and sports engines but also in adoption of their general design
principles for power output for even humble production engines

[xpensive]

All of which is most informative, thanks strad, but just like someone pointed out, is there anyway of learning how the
F1-engine's efficiency has improved since then?

[SeijaKessen]

Just from shear longevity and acomplishment I would say the Cosworth...Wasn't the Weslake rather finicky?
My suspision lies in cylinder turbulence and filling where Cosworth had the upper hand.
I would agree with this quote

The performance of the Cosworth DFV was remarkable in 1967 when first raced yet, after 16
years of steady improvement, it was finally over 30% better in power/weight ratio and was
sold at 34% lower price in constant money terms (excluding VAT). It was a triumph of design
followed by a triumph of development, whose 154 Championship Grand Prix victories surely
will never be beaten.

Not only did Ford receive a magnificent bargain in advertising from its initial £100,000

(£1.5M at 2008 level) but so did the customers and Cosworth also profited.
The influence of the Cosworth FVA and DFV engines has spread far and wide since their
racing days, not only in racing and sports engines but also in adoption of their general design
principles for power output for even humble production engines

I recall something being said that the Weslake V12 actually had a design flaw that could/was not be corrected. It caused the engine to begin to lose power during the race.

[xpensive]

Harry Weslake was an old fart already back then, he couldn't get much right, not even the 1973 iteration with Ford-money was good enough for sportscars as I can recall?

[SeijaKessen]

I'm going off memory, but I think the Weslake Capri of 1972 won it's class in Le Mans, and pretty much ran the gauntlet in the Euro Touring Car Championship, only not winning 1 race.

Edit: I see you changed it to 1973. The Fords were 2nd and 3rd behind BMW. Not a total loss, but nowhere near as dominant as they were in '72 obviously.

[xpensive]

I'm talking the 3-litre prototype-class you schmuck, when the Gulf Mirage-Weslake was facing Ferrari 312 PB and Matra MS670!

[strad]

Ahh I see...I'm sorry..mis understood...I think the Weslake had a habit of burning up it's valves.

[SeijaKessen]

I'm talking the 3-litre prototype-class you schmuck, when the Gulf Mirage-Weslake was facing Ferrari 312 PB and Matra MS670!

It must be the booze talking.

I have no idea why I was even thinking of Euro Touring Cars.

Good god, it's one of those days.

But yes, the performance the Mirage with the Weslake V12, turned in at Le Mans in '73 was one for the ages.

I can't decide if abysmal even adequately describes it relative to the Cosworth.

[gato azul]

[xpensive]

Funny sportscar season that 1973, while the 12-cylinders where nowhere in F1, they ruled sportscars with Ferrari and Matra, while that Ford-sponsored Weslake V12 was a dog in John Wyer's Gulf Mirages.

Back on topic, where do we begin, how much fuel did a Cosworth kit-car carry at the time, 240 liters comes to mind?

[Tommy Cookers]

having again crashed around trying to read enough of the Roy Franklin E book 'PLAN' it seems clear to me at this moment

that the 60s reinvention of the narrow angle 4 valve was 63 onwards Shell funded research at Weslake for/with BRM (together they had discovered that BRM race winning combustion was inconsistent)
Dan Gurney signed up in 64 for a 3 litre V12 for the 66 F1
a test engine had been widely shown by 65
the 65 race winning 350cc MV Agusta was similarly a narrow angle (unlike others eg Honda)

so this must have boosted Mr Duckworth's confidence' leading to the BDA in 65 ?
at the time the general expectation was a Cosworth V 12 like the SCA (notorious for the 72 degree ign advance needed)

Weslake sold engines to DG when it was meant as research for the benefit of BRM ??


I regard all engines as BC (before Cosworth) or AC (after Cosworth) ..... I thought everyone did !!