TWIN CAM ENGINE TECH MEMO
The TC-88 and TC-88B engines have a small, die cast, crank-speed gerotor style oil pump that utilizes a spring washer to preload the pump gears against the cam support plate and pump housing. The side loading from the spring washer can cause excessive friction and premature wear.

The TC-88 engine uses a dry-sump lubrication system. To perform properly, the dry sump system requires a properly sized, BALANCED SYSTEM including a scavenge pump that is capable of removing all residual oil from the crankcase at all engine speeds and conditions. Failure of the scavenge pump to perform to these requirements causes “WET SUMPING.” Instead of returning to the oil tank, the oil builds up in the crankcase and cam chest causing excessive friction/power loss and oil aeration. This can result in oil being forced out the breather, air cleaner contamination, oil leaks, loss of oil supply, lifter clatter, component wear and potential engine failure.

TC-88 engines have piston cooling jets that are designed to squirt oil on the under side of the pistons. These jets have a check valve that opens at approximately 25-28 PSI oil pressure. Without adequate pressure pump volume this pressure regulated oil flow to the jets can short circuit critical oil flow from the lifters and top end.
Twin Cam valve springs need oil for cooling. Inadequate oil flow can cause excessive valve spring temperature causing loss of spring tension resulting in noisy valve train separation and potential engine failure. Inadequate oil supply to the rocker boxes can cause excessive rocker arm bushing wear and component failure.

The Twin Cam crankshaft has machined “paddles” on the periphery of the left flywheel to provide a trigger for the crank position sensor (CPS). These paddles can whip up unscavenged oil in the crankcase, turning the oil into aerated frothing “peanut butter” that pushes its way up into the rocker boxes-out the breather, into the air cleaner and beyond!

Feuling Oil Pump Corp. has a high efficiency, billet, bolt-in replacement oil pump for the TC-88 and TC-88B engines that provides 40% more supply volume and 60% more scavenge volume than the stock TC-88 oil pump. Large diameter gerotors, aerospace materials and tolerances create a high efficiency pump without the need for a high friction spring washer. We have optimized our hydraulic roller lifters to work with the Feuling Oil Pump as a BALANCED SYSTEM.

The dyno-developed and track tested combination of FeulingComponents will allow the Twin Cam engine to provide maximum power, reliability and longevity.

The Feuling products are THE solution!