The Engine

The Engine
The
Engine
V6 Duratec
While Ford has reaped the Duratec's benefit, it was not an original design. The primary input for the design of this
engine was Porsche, which was already developing the configuration for other purposes. Porsche sold the engineering
to Ford and Cosworth, the dominant force behind the cylinder head design. There is actually a 6.0L V-12 Duratec
configuration used in the Aston Martin, which is custom built for each vehicle by Cosworth in England
The Duratec engines have rapidly become Ford's finest engine launch in history. The engine ranked second in J.D.
Power & Associates' satisfaction survey for 1996 and boasts zero claims against oil consumption.
The Duratec 30 is a 60 degree V6.It has an aluminum block with cast iron liners, aluminum DOHC cylinder head with four valves per
cylinder, fracture-split (cracked) forged powder metal connecting rods, and a forged steel crankshaft.
There are two versions of the Duratec 30:
DAMB - Lincoln LS, Jaguar, Mazda 6 and MPV, which use direct-acting mechanical bucket (DAMB) tappets. Here the camshaft sits
directly above the valves with different thickness pucks for adjustment. Output is 232 hp.
RFF-Taurus/Sable/Escape/Tribute use roller finger followers (RFF) with the camshaft offset acting on the roller, which pivot on a
hydraulic lash compensator. Output is 208 hp.
Jaguar AJ-V6 engine/AJ-30
The Jaguar AJ-V6 engine is
a specialized version of
Ford's Duratec 25/30 V6.
One notable addition is the
use of variable valve timing,
a feature also shared with
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The Engine
Mazda's version of the
engine. It is available in 2.0
L, 2.5 L and 3.0 L
displacements.
Jaguar's AJ-V6 engine has an aluminium engine block and aluminium DOHC cylinder heads. It uses SFI fuel injection,
has 4 valves per cylinder with VVT and features fracture-split forged powder metal connecting rods and a one-piece
cast camshaft, another differentiator from the Ford and Mazda versions.
AJ30
The AJ30 is a 3.0 L (2967 cc) version and is the most common, especially considering the Duratec 30. It has an 89 mm
bore and shares the 2.5's 79.5 mm stroke. In the S-Type, it produces 240 hp and 216 ft-lb.
Amongst others this engine is used in:2000–present Jaguar S-Type, 240 hp (179 kW) and 216 ft-lb (293 N·m)
2002–present Jaguar X-Type, 231 hp (172 kW) and 209 ft-lb (283 N·m)
2009–present Jaguar XF,
240 hp (179 kW) and 221 ft-lb (300 N·m)
The Jaguar XF will debut a refined version of the AJ30 with continuously variable cam-phasing and variable geometry air
intakes to increase power and broaden the power band up to its 6800 rpm redline.
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The Engine
Esprit v6
The reason for
choosing this engine
for the Esprit is
because it seemed
to tick all the right
boxes. I was
looking for a
replacement unit
that had to meet
certain criteria in
that it needed to
be, powerful, light
and compact, but also, reliable and economical to run.
The Jaguar AJ30 is the engine I used for this conversion. Mine came from a 2001 S-Type with about 60K on it.
Due to the more traditional layout of the Jaguar being, front engine/rear wheel drive, meant this engine
being longitudinally mounted in the S-Type, as opposed to transverse mounted as in the X-Type, was designed to face
the same way as in the Esprit, (north-south) This meant the exhaust manifolds were usable as they were
both facing towards the rear, the engine mounts were roughly in the right place and the cooling system is all fed from the
front by a separate and easily removable water pump.
Also, maybe this variant could be the better choice due to Jaguar's engineering input in it's final design, and with the
inclusion of variable valve timing amongst other things.
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The Engine
These pictures
show the engine
after being cleaned
up, painted and
fitted to the Esprit's
UN1 transaxle.
This was done using
a machined alloy
adaptor plate
between the engine
and bell housing,
and a mixture
of Jaguar and Lotus clutch parts.
Another modification needed was the original Jaguar sump and oil pickup pipe had to be removed and replaced with one
from a 2.5L V6 Ford variant. This was due to clearance needed around one of the Esprit's lower chassis cross members.
Also a modified 2.5L inlet manifold was used due to height restrictions in the engine bay, and because the Jaguar
manifold was to big.
These V6's share a very similar basic engine design, this meant that both sump bolt patterns were identical and it was a
straight swap between them without any problems. The inlet manifold however did require adapter plates to be made
due to the heads being slightly different,although the inlet openings are spaced the same. The throttle opening was also
widened to help cope with the slightly larger engine capacity.
There were some other modifications needed along the way, and I shall try to cover these in more detail in the
installation section.
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The Engine
Here's the Engine in its final resting place in the back of the Esprit.
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The Engine
Duratec 35
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The Engine
The Duratec 35 (code-name Cyclone) is a new 3.5 liter V6 that will appear in 2005. It is an all-aluminum engine based
on the Duratec 30, and adds variable valve timing, a feature already found on the Jaguar AJ30 and Mazda AJ versions
of the 3.0. Its displacement can be increased to 3.8 liters, meaning a Duratec 38 could come soon after.
The aluminum block is made by Teksid in Alabama, while the heads come from Newmak in Mexico, and the crankshaft
comes from Bharat Forge of India. The engine will be assembled in Lima, Ohio
The Duratec 35 3.5-liter V6 engine is capable of pumping out an output of 265 hp (198 kW) and 250 ft•lbf (339 Nm) of
peak torque. It also offers an impressive fuel economy and low exhausts emissions.
Ford's Lima Engine Plant in Ohio is currently producing about 325,000 of the 3.5-liter Duratec 35 engine, and the plant
will be a model for Ford Motor Company’s flexible manufacturing that will allow different models and products to be
produced faster and with less cost in a single assembly line. Ford also said the Duratec 3.5 V6 engine will “power as
many as 20 percent of its vehicles by the end of the decade.
Ward’s Auto World named it as one of the 10 best engines of the year 2007 — the first time a debut engine received such
an honor. Ward’s called it a "brilliant performer" with class leading refinement.
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