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- FORD'S ZETEC-R; MAKING THE BEST EVEN BETTER
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-
- Ford and Cosworth were faced with a major challenge for
- 1995: to ensure the Zetec-R retained its winning ways.
- Ford's brand-new Formula One engine was the dominant force
- of the 1994 season, powering Michael Schumacher to victory
- in eight Grand Prix and making the young German the 13th
- driver in 26 years to have won the World Championship with
- Ford power.
-
- For the coming season, however, motorsport's governing
- body, the FIA, has introduced a number of significant
- changes to the Formula One technical regulations. These
- include a reduction in engine capacity, from 3.5-litres to
- 3.0 litres. It was therefore back to the drawing board for
- the engineers who had developed Ford's 1994 engine.
-
- As might be expected, the new Zetec-R has been based on
- last year's successful engine. The external appearance
- remains very similar to the 3.5-litre V8, although there
- are small, noticeable differences to allow for the new
- "stepped floor" regulations. Inside the engine, however,
- the story is quite different.
-
- The 1995 Zetec-R has a new crankshaft, connecting rods,
- pistons, cylinder liners, cylinder heads, front cover,
- valves, air-valve spring assemblies and inlet system. In
- addition, there are modifications to the cam drive
- arrangement and some of the auxiliaries, all of which are
- dictated by the need to run the engine at higher speeds.
-
- The result is a 3.0-litre V8 which will begin its racing
- life with a maximum engine speed limit of over 15,000 rpm.
- That equates to 250 revolutions per second. Despite the
- severity of the task, however, the new Zetec-R has already
- successfully completed a number of simulated race distances
- on Cosworth's transient dynamometer, running to maximum
- revs in all the gears.
-
- In terms of technical details, the 3.0-litre Zetec-R shares
- the same 75-degree vee angle and external dimensions as the
- 3.5-litre version. Internally, it incorporates titanium
- connecting rods and valves plus special alloy pistons. As
- in the previous version of the Zetec-R, ceramics are
- incorporated in the cylinder heads and a great deal of
- attention has been paid throughout the design process to
- minimising heat rejections and maximising the stiffness of
- the engine in the car.
-
- From a performance standpoint, it is not valid to compare
- the new engine with its predecessor. Since the beginning of
- the 1994 season, a number of changes have been legislated
- by the FIA to reduce vehicle performance, including the
- venting of airboxes to prevent pressurising engine air at
- high speed and the requirement to use pump fuels instead
- of special blends.
-
- The effects of these two changes alone reduced the engine
- power on fast straights by about 7 per cent, and these
- losses cannot be recovered. In addition, the reduction in
- swept volume of 14 per cent will, at constant engine speed,
- result in a 14 per cent power loss, which equates to over
- 100 horsepower in the case of a current-specification
- Formula One engine.
-
- Despite this constraint, however, by incorporating lessons
- learned from the 1994 Zetec-R program as well as from a
- number of ongoing research projects, Ford and Cosworth
- engineers have already substantially exceeded their
- performance goal of reaching 86 per cent of the power
- output of the 3.5-litre Zetec-R.
-
- In fact, the 1995-specification engine already boasts the
- highest horsepower per litre figure of any naturally
- aspirated engine the company has ever produced. Despite
- this drive for power, however, it was not the primary
- consideration of the engineers.
-
- "Peak horsepower has never been our objective," says Peter
- Gillitzer, Ford's Director of European Motorsport. "We have
- always sacrificed peak power for mid-range torque. The
- majority of European circuits respond to driveability and
- consistenfiy progressive torque. We think this will be of
- even greater importance in 1995, when all teams will suffer
- from reduced downforce."
-
- In short, then, the 1995 specification Zetec-R is already a
- better engine for a given. capacity than it was in 1994.
- That has got to be good news for the Sauber-Ford team, but
- a worrying development for the rest of the Formula One
- grid.
-
-
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- Source: PP Sauber AG
- Scan & ocr by Tero Virta
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