This cylinder head is based on a selected second hand
injection cylinder head. These are carefully cleaned removing
all traces of coke, oil and dirt. All old bearings are
removed, threads are checked for depth and condition.
Waterways are checked for cleanliness. We then pressure test
to 70 P.S.I
The inlet port on an injection cylinder head is a lot
higher than the standard cylinder head because of the shape
required to site the injectors on a road car, so we clean out
the bottom of the port with a die grinder to allow an alloy
stuffer, designed in house, to blend in and locate without
thin edges. The cylinder head is then drilled and tapped to accommodate
two 1/4 U.N.C. Allen bolts to hold each stuffer.
We then locate the cylinder head to a jig and the valve
guide holes and valve seats are machined at precise angles and
The cylinder head is now jigged and the inlet port is
drilled and bored in its new position and angle.
The inlet manifold stud holes are now filled in and
re-drilled and tapped to 0.2" further up the cylinder
head. This enables the standard two litre inlet manifold
gasket and manifold shape to fit the modified parts.
The combustion chambers are polished, balanced and blended
into the new valve seats. The exhaust ports are gas flowed out
to relieve restriction around the valve guide area and the top
front area of the port at the head face. This process alone
takes 24 man hours and is all done personally by Andrew
Brooks, Dave's son who has 25 years experience of all the
machinery and process's involved in our business
One 6x1 mm Thread is drilled and tapped on the exhaust side
of each cam pillar to locate a splash shield for use with a
cross drilled camshaft.
The cylinder head is finished off with bronze valve guides,1.75"in
& 1.5"ex in forged stainless steel valves with single
collet grooves, allso bronze cam bearings. There is a choice of
valve springs depending on cam choice
Each cylinder head is stamped so that it is easily recognizable
in the future and can include customers own name.
The price for this service is based on an exchange head
from the customer. £100 surcharge will be levied if no
exchange head is available.
Price to this specification on application
We have now developed further modifications to this head
which includes cast welding the combustion chamber and
reshaping to further improve inlet flow. This mod also
shortens the flame path and improves combustion and power.
Price to this extra specification on application