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Cylinder heads: our specialist services

Article by: Hannah in General - 24 June

As you walk through the workshop each day, you’ll always see something different to the day before. The same noises fill the space – machines turning, the hot wash steaming and tools clinking. But the work that fills the shop is always varied.

A little different to his usual work load, as I walked through this morning, Dennis was working on a French tractor cylinder head. This cylinder head had had a crack previously repaired but the first job on Dennis’ list was to pressure test. If the results were good, new valves would be fitted, the seats recut and the head re-faced.

Although not our usual mix of vehicle, the process of re-conditioning this cylinder head is Fiennes Performance’s bread and butter. But what other cylinder head services do they offer? We’d like to share with you a few of the modifications and services Fiennes Performance can carry out on the cylinder head for your engine, be it big or small!

Conversion to lead-free:  Modern fuels, with lower lead content, can burn away the valve seats allowing gases and oil to flow through. To eliminate this risk, Fiennes Performance machine out the existing seat, machining a pocket to insert, press and interference fit in a hardened seat, not susceptible to the modern fuel effects.

Gas flowing: this process involves re-profiling the chamber of the inlet and exhaust ports, increasing the surface area, also ensuring the chambers are smooth or polished, allowing the gases to flow more efficiently and thereby improving the performance of an engine.

Fitting of oversized valves: this increases the amount of air and fuel mixture drawn into the cylinder, also the flow of waste exhaust gases out of the combustion chamber enhancing the engine’s performance and efficiency.

Welding: whether it be a small area of corrosion or a crack in the cylinder head, Fiennes Performance can offer specialist welding to repair, machine as required, restore or modify to agreed specification.

These are just a few of the services we offer at Fiennes Performance, for more information visit the Specialisms page on our website or get in touch via our Contact page.