Capri V6 conversion (3.0 X30XE)
Capri has been the recipient of a variety of engines over
the years. More recently, the Granada Scorpio 2.9 engine swap
has become common place. However, these engines are becoming
hard to find in good order (with according prices). Therefore
this owner decided to use a Vauxhall V6 as the basis for conversion.
Normally found in 2.5 litre form, this engine is actually
a 3.0 from an Omega. These cars are rear wheel drive to start
with, so can often be found with manual gearboxes as standard.
the following details will be useful to other owners contemplating
such a conversion...
3.0 Vauxhall V6 produces 210bhp, so performance is on a par
with the Cosworth. Engines are much cheaper to start with,
and availability of spares is no problem as they were also
fitted to Vectras, Calibras and Cavaliers.
The car was
converted to run with power steering at the same time as the
engine conversion, therefore the Vauxhall power steering pump
was retained and used with the Ford steering rack. The air
conditioning pump was no longer needed, and to save space
a Calibra steering pump and drivebelt are fitted.
were a pair of engine mounts (custom made, but bolting to
the original Capri crossmember). The Omega sump and oil pickup
pipe were replaced with Calibra items - this meant only slight
modification to the crossmember was required :
To make way
for the V6 cylinder configuration (and power steering pump)
the battery box was recessed into the inner wing area - this
is a common modification on Capris. The radiator was upgraded
to an Astra TD item.
propshaft was made from the original Capri and Omega items.
The gear stick exit is in the original Capri location (effected
by shortening the change mechanism). However the tunnel did
have to be raised slightly to clear the larger gearbox. With
carpets back in the car you are unable to tell however.
To mate the
propshaft to the rear of the gearbox, the adaptor plate shown
below was machined:
of the Vauxhall conversion - very cheap running costs. The
cam belt and water pump being renewed.
To give clearance
under the bonnet, the plenum chamber was removed and rotated
through 180 degrees (such that the throttle butterflies face
the rear of the car). Luckily the inlet manifolds are symmetrical.
ECU uses the original 60-2 trigger wheel (mounted inside the
block, on the crank), and the original coolant sensor. The
restrictive air flow sensor was replaced with a Vauxhall MAP
sensor, and ignition is controlled via wasted spark with the
original Omega coil pack.
fan is controlled thermostatically by the ECU. The idle speed
is also maintained at all temperatures by closed loop control
(ie. the ECU will speed up / slow down the engine if it is
too slow / fast).
mapping with a wideband lambda sensor, the engine is now run
with a narrow band sensor just to keep an eye on economy figures.
The car now has double the original power that the 2.0 Pinto
provided, and gives 25mpg - the Pinto managed only 26.
Below - rolling
road plot from Z Cars in East Yorkshire. 238 bhp with the
only modifications being free-flow exhausts, K&N filters
and Canems ECU. (Click for a larger view). We were also testing
a prototype LPG system on the same day - hence the two lower
readings 'Test2' and 'Test3'.