Porsche Engine Machining

Call us for expert advice and a quotation for your engine machining requirements.

H T Howard offer a range of machining services specifically tailored to repair Porsche engine components.

These unique high performance engines require some dedicated machining operations which can differ from those methods used to repair more conventional engines.

Porsche 356/912 Head Gasket Recess Machining 

Many Porsche and VW air cooled engines rely on thin rings fitted into a recess in the cylinder heads between the head and barrel to maintain the head gasket seal.

Following any head gasket failure it is good practice to machine the cylinder head sealing faces to correct any distortion and prevent further problems developing. In extreme cases this becomes absolutely essential in order to avoid premature failure of the new gasket seal as the sealing face will have become distorted and damaged.

During the machining operation, each surface is accurately machined to an equal depth ensuring that the finished job sits squarely on the parent liners. In turn, each pair of cylinder heads has all sealing surfaces machined equally to maintain compression ratios between all cylinders.

It is also possible to enlarge the recesses to accept oversize cylinder barrels used in high performance and race engine applications.

Porsche 356/912 Valve Guide Replacement

Many cylinder heads we now see from these vehicles have unfortunately suffered sub standard repairs over the preceding years.  The area most often affected is the valve guides which have often been poorly fitted into housings which are worn or distorted following a previous failure often caused by the original guides becoming loose during service.

H T Howard are able to offer a service to rectify these problems by machining out the damaged guide housings and fitting oversize valve guides.

The valve seats can then be machined to correct any alignment issues in the conventional way on our Serdi 100 valve seat machining centre.

Porsche 911 (Air Cooled) Head Gasket Recess Machining

As with the 356/912 above, H T Howard are able to machine damaged head gasket sealing faces on any of the air cooled boxer engine range.

Using a dedicated jig to ensure total accuracy and in conjunction with our BERCO AC650M each head is individually machined to maintain both alignment of the camshaft carrier assembly and equal compression ratio between all cylinders.

We have also carried out machining operations to allow fitment of oversize cylinder liners for high performance and race engine applications.

Porsche 911 (Air Cooled) Valve Guide Replacement

Once again in common with the 356/912 above, many 911 air cooled cylinder heads have also suffered poor repairs in the past.  H T Howard offer the same service for machining damaged valve guide housings and replacement oversize valve guides and where no previous damage exists we are also able to offer a standard replacement service.

As an alternative to full replacement, Porsche cylinder heads are suitable for repair using our bronze valve guide sleeving system.

Following any work involving valve guide repair, cylinder heads will need to have their valve seats machined utilising our Serdi 100 machining centre.

Porsche 911 (Air Cooled) Crankcase Machining

Early air cooled Porsche 911 engines can be uprated and given a capacity increase by fitting larger cylinder barrels and matching pistons.  This conversion necessitates enlargement of the crankcase apertures which the cylinder liners fit into.  At H T Howard we carry out this machining operation using our BERCO AC650M boring machine.

Porsche 996/997 Cylinder Block – Liner Conversion

Porsche water cooled boxer engines have cylinder bores where the pistons run directly in the aluminium of the cylinder block itself.  When damage occurs, H T Howard can machine out the damaged cylinder bores and fit replacement cast iron liners for a cost effective repair.

Call us for expert advice and a quotation for your engine machining requirements.