Honda k20 block conversions
We can now machine engine blocks in-house to enable the fitment of any sized pistons from 86mm (std) to 90mm+. Block boring 86mm to 87.5mm can be performed directly into the standard Honda K20a cast-in liners
Piston sizes 87.5mm+ require the fitment of wet liners / sleeves either straight sided in conjunction with a CNC machined blockguard or alternatively all in one Darton MID ductile cast iron items can be installed.
The fitment of our 90mm pistons gives a capacity of 2188cc on a standard stroke crank and with the combination of increased compression and de-shrouded valves gives a solid 27bhp increase on the dyno.
Successful installiation of wet or Darton MID ductile cast iron liners / sleeves is dependent on accurate sizing and correct spacing which is not possible with standard bore centred machines.
All boring is performed on a new 4 axis Hurco machining centre using dedicated block jigs and torque plates. Bores are then hot-honed on a Sunnen machine to give round accurate bores which are perpendicular to the crankshaft.
Bored blocks can be combined with various stroke crankshafts to give capacity increases from 2.1 to 2.6 litres.