S65 4.2L Engine Rebuild

This engine includes replacement of the OEM rod bearings with high performance bearings, CarBahn Autoworks valve springs, 2mm over-sized 94mm CarBahn-CP forged pistons and head gaskets.

Connecting rod bearing and valve springs are common failure items on S65 and S85 engines. In response, CarBahn Autoworks has developed improved bearings and valve springs. This rebuild includes a valve job with new hydraulic lifters, plus timing chains, timing chain guides, timing chain tensioners and all associated seals and gaskets.

History

Steve Dinan has been building high performance and racing engines for BMW s since 1977, winning 11 racing championships including 3 prototype championships and two 24 Hours of Daytona. The same engine shop that builds the racing engines also builds the street car engines; these talented engineers, machinists, and builders have built hundreds of engines from OEM street rebuilds to full-blown racing engines.

Refer to the graphs below for the power results without catalytic converters on 100 octane race gas and using J607 (the typical aftermarket correction).

S65 4.2L Wet sump:

No cats, 100 octane unleaded, J607

Engine core acceptance parameters

Must be complete core (factory engine, from oil pan to valve cover)

• Block must have no:
  • Holes or cracks in casting
  • Holes or crack in covers
  • Bore damage that cannot be honed out
  • Thrust surface damage
  • Journal surfaces damage
  • Bolt hole damage that can’t be repaired
• Heads must have no:
  • Holes or cracks in casting
  • Holes or crack in covers
  • Thrust surface damage
  • Journal surfaces damage
  • Bolt hole damage that can’t be repaired
• Additional repair charges could apply for damaged items that are not normally changed during an overhaul and cannot be repaired or serviced
  • Valves
  • Crankshafts
  • Camshafts
  • Guides
  • ValveTronic mechanism
  • Vanos mechanism