001 - Lead-free conversion
We can carry out all the required work necessary to allow your car to run on readily available lead-free fuel.
Send us your cylinder head and we shall strip off the springs, caps and spring seats.
We will remove the original guides, shot blast the cylinder head to remove the rust and corrosion.
Then we will supply and fit the new stellite hardened valve seats to the exhausts, fit our bronze valve guides with the modified tops to accept improved valve stem oil seals.
New valves are fitted. If your head is from a TB, TC or early TD then we can supply and fit the larger TF size valve at no extra cost. This will improve the breathing of the engine and allow the engine to run more smoothly.
On the side of the cylinder head is the inlet and exhaust ports. These are very poorly ported from the factory.
Included within the cost of the lead-free conversion is the advanced porting of the ports. The exhaust ports are opened up to be closer in size to the exhaust manifold and gasket. The inlet port has a large flat surface separating the ports. This massively disturbs the air flow and makes the siamese ports work less efficiently. We flow and edge the dividing section to improve the flow.
This work is not carried out purely to increase performance (although it does give an average increase of 5 bhp) but to improve the idle and drivability of the engine, particularly now that we are using a lower octane level fuel.
The Cylinder head is then re-faced to ensure it is true. Then it is thoroughly cleaned and re assemble using improved stem seal, your original springs, caps etc.
The whole process is a cylinder head overhaul and performance improvement.