Land Rover Performance Tuning - Power Plus - Land Rover cylinder heads, camshafts, SU Carb system, 2.8 engines - ACR - Automotive Component Remanufacturing Ltd
Engine Test and Development
Landrover Products and Services
  Contact Us

Performance Tuning
Remanufactured Engines
Cylinder Heads


News image to go here
All performance heads run with
lead free fuels

The Power Plus © performance tuning system has been
developed to provide owners of classic Series 11, 11a, 111
and 90 / 110 Land Rovers fitted with the 2.25 / 2.5 petrol
unit with extra power and efficiency. The system has been
used on every continent and in every situation Land Rovers
may be found. The Power Plus © system offers levels of extra
performance to suit the application and budget of each
requirement without compromising the legendary reliability
of the Land Rover 4 cylinder unit.

The Power Plus © tuning system allows the engine to produce
more torque especially in the low to mid range. This results
in faster acceleration, less gear changing and the ability to
maintain speed on gradients. This makes the Land Rover
easier and safer to drive both on and off the road.

The 2286cc petrol engine was developed for the Series
11 Land Rover, launched in 1958. It featured many common
components and dimensions to the diesel version of this
engine. This enabled Land Rover to produce both versions
of the engine with the same machine tools and production
line. As a result the petrol version was considerably over
engineered for its 115 FtLb of torque and 67 BHP.

Over the years remarkably little changed. 1980 Saw the
introduction of 5 main bearing crankshafts, and 1985 a longer
throw crank shaft raised capacity to 2495cc The petrol engine
continued in production until 1992, when Land Rover deleted
the petrol unit from its product range. The diesel version
continued in the form of the 200 and later the 300 TDI unit.
Although Land Rover no longer manufacture the 4 cylinder
engine, it is still in production in Brazil. Developed further, now
with a capacity of 2.8 litres and used in the South American built
Ford Ranger Pick up. From the engine tuners point of view the
2.25 / 2.5 engine is ideal. The cylinder head design was modern
for the 1950s and material thickness is generous, allowing the
tuner to raise compression ratios and reshape the ports to
give great increases in air flow. Manifolding and carburation
is restrictive, and camshaft profile is very mild indeed. This,
combined with an exceptionally robust design, allows massive
power gains without the risk of shortening the life or reliability
of the unit.

The cylinder head is the first thing to consider when tuning the 4 cylinder unit, as big gains can be made from this change alone.

When considering performance cylinder heads it is worth specifying 9:1 compression as this raises overall efficiency, yet is still suitable for standard (95RON) lead free fuel.

The airflow efficiency of the inlet and exhaust ports has a direct bearing on engine torque and power.  ACR have invested considerable time and resources to develop, using airflow and dynamometer test techniques, the most efficient port designs, with the highest airflow rates possible, yet retain compact port areas, vital to low speed torque and fuel efficiency.

These ultimate port profiles are, on our Stage 2.1 cylinder heads re-created (uniquely in this field) using advanced CNC machining technology on every production item we produce.  This completely eliminates all hand working of ports.  Solid bronze valve guides, and further CNC machining of valve seats all add up to produce the most advanced cylinder heads available.

All our performance heads feature solid bronze valve guides, suitable for lead free fuel. Stage 2.1 heads are specified with 9:1 compression as standard, with the choice of 8:1 or 9:1 on Stage 1 units. 9:1 units are suitable for use with regular 95RON lead free fuel. The 9:1 compression improves thermal efficiency, and is strongly recommended. It is particularly useful with LPG fuel.

All our cylinder heads are supplied built up, ready to fit and with a decoke gasket set provided. Available on an exchange or outright sale basis.

Consider the Stage 2.1 Cylinder Head if using with other Power Plus © products

Stage 1 8:1 cr +  6 BHP on standard engine

Stage 1 9:1 cr  +  6-8 BHP on standard engine

Stage 2.1 9:1 cr + 15 BHP on standard engine

Click for prices


This system is supplied in two formats, one for leaf sprung
Land Rovers and one for coil sprung vehicles. The leaf sprung
kit consists of the new intake manifold casting, HS6 SU
carburettor, K+N air filter and all fixings, gaskets and fitting
instructions. A free flow exhaust silencer is included
( also available separately ) Please specify if 88" or 109" wheel
base. The carb is ready jetted to suit, with a thicker, lean
calibration needle option available for high altitude.

Coil sprung Land Rovers have a more efficient exhaust so do
not require the silencer. They do however need a modified
exhaust manifold, so this is included instead.

For LPG fuel users we can supply the correct sized adapter
for the SU carb.

Power Plus © carb + Stage 2 Head + 30 BHP over standard.

Click for price

News image to go here
Power Plus SU Carb system for
leaf sprung models


This camshaft has been developed to improve torque output.
There is more torque at every point in the rev range.
The camshaft is manufactured from new (not a re-profile)
and has a higher rate of valve acceleration and lift.
The camshaft requires "timing in" to function correctly
(instructions included). The last of the 2.25 and 2.5 engines
will need an early 6 way chainwheel to position it correctly.
Tappets are of the roller design. If any doubt as to their
condition, we stock new heavy duty items.

Power Plus © Camshaft + SU carb + Stage 2 Head + 43 BHP
over standard.

Click for price

News image to go here
More torque at every point in the
rev range


This tubular manifold is of the 4:1 design. and connects
to the standard inter pipe. It includes fixings and gasket.
Users report a MPG improvement as well as power increase.
We can modify this to fit coil sprung models too.


This unit is based on the 5 main bearing 2.25 or the
2.5 engine. It features 95 x 97 mm bore / stroke and
is supplied as a stripped unit with the Stage 2 Head,
Power Plus
SU carb and Camshaft. Where it replace
a 3 main bearing unit the parts (Fly wheel etc.) required
to convert can be added. For customers who have already
some or all of the Power Plus © system installed on their
Land Rover, in most cases this can be re used.

Power Plus © 2.8 Stripped Engine with Stage2 Head SU carb
and Camshaft produces the following output:

177 FtLb @ 2300 RPM 117 BHP @ 4100 RPM.

Click for price


Cost effective system to replace the points in a Lucas
distributor. Useful with higher compression ratios and LPG fuel.

Click for price


This is the ultimate ignition for the Land Rover engine.
The mechanical distributor is removed and replaced with
a core plug to seal the redundant hole. The spark is provided
by a waterproof coil pack. This is controlled by a micro
processor which picks up a load signal from a manifold
mounted pressure sensor, and crank shaft speed and position
from a sensor mounted on the fly wheel housing which reads
the 36-1 teeth machined on the fly wheel. The engine
management system is user programmable to set the correct
spark timing for every load and RPM. This results in better
part throttle power and economy. The system does much
more, as it has programmable rev limit, shift light and many
otherfeatures. We provide the system pre-mapped when
specified with an engine, User mapping is possible with
a laptop computer and it is even possible to data log the
engines performance and sensor parameters whist running.

Click for price


We can build an engine or Power Plus © package to your
specification. Popular packages include the following:

3 main bearing 2.25 remanufactured unit with Stage 2 Head,
Power Plus © Camshaft, and SU carb.

Click for price

Stage 2 Head, SU carb, Power Plus © Camshaft and 4:1
Tubular Manifold.

Click for price

| News | Engine Management Systems and Dynamometer Testing | Land Rover Products and Services
V8 Performance Engines |Electronic Tansmission Control | Prices | Testimonials | Contact Us
Downloads | Links | Articles