Piston Services

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

H T Howard & Co offer various services relating to piston machining and re-manufacturing so whether you are rebuilding a standard engine and re-using the original components or performance tuning a modified engine and require specialist machining services we have the machinery and experience to help you with the job in hand.

Crown Machining

 From combustion bowl machining and re-profiling for high performance and turbo applications to simple piston crown topping for diesel engines, H T Howard offer a range of machining solutions for your engine.

 Valve Pockets

Where required, H T Howard have the capacity to machine valve pockets into piston crowns as part of high lift camshaft and similar conversions.


At H T Howard we are able to check and correct the balance of pistons to more accurate tolerances than is usual with off the shelf products.  Even manufacturers of “performance” pistons use relatively wide tolerances which can be improved on resulting in smoother running engines which are under less stress.

 Ring Gaps

Many aftermarket pistons are supplied with ring packs that require the end gaps to be set depending on the severity of the application.  Higher performance engines, particularly those with turbochargers or superchargers fitted will require increased ring gaps as well as those engines running on non-standard fuels.  Higher performance engines create more heat which in turn means greater expansion within the upper cylinder components including the piston rings.  As cylinder temperatures rise the ring end gaps and groove clearances will reduce and if set too tightly will result in ring binding and ultimately seizure.  H T Howard offer a service to individually set the ring end gaps to the exact specification required for your application which means your engine will perform efficiently and create more power.


H T Howard offer a complete piston ring fitting service and ensure that all ring grooves are correctly cleaned before new rings are fitted.  If required, piston ring end gaps can also be checked and adjusted as necessary.  As part of this service ring groove and piston skirt wear can also be checked.  Additionally, and where practical, we are also able to remove and refit the pistons onto their connecting rods and check for small end bush wear as well as a number of other piston and con-rod related problems.


All pistons have a wrist pin or gudgeon pin which fits through both the piston and connecting rod and which links them together.

There are three main methods used for attaching these pins to their respective connecting rods utilising circlips, pinch bolts and friction or press fitting.

H T Howard we have specialist equipment including jigs and fixtures to enable us to carry out any piston fitting operation.

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