Project EJ Civic, Building the Drivetrain


To make the car more responsive and free up some drag created by rotating mass we ditched the stock flywheel and installed ACT’s XACT Prolite flywheel.  ACT flywheels are one piece steel machined from chrome-moly forgings.  Chrome Moly is a steel alloy with a high chromium and molybdenum content.   This makes a steel alloy with nearly twice the tensile strength per weight as regular high carbon steel.  Forging is also cool as it orients the metal’s grain for best strength.  It also works the metal and refines the grain which again makes for additional strength.

At 8.8 pounds the forged chrome moly ACT Prolite flywheel is less than half the weight of the stock 18 lb part.

The ACT flywheel weighs in at 8.8 lbs, less than half the weight of the stock 18 lb part.  The Prolite flywheel is usually recommended for road racing and is lighter than ACT’s street oriented Streetlite flywheel due to its lightening slots milled around the periphery of the flywheel where they have the greatest impact on rotational inertia.

The ACT flywheel’s ring gear teeth are forged into the flywheel.  No coming loose here!  Holes milled into the flywheels perimeter reduce the rotational inertia.  The ACT flywheel can be resurfaced safely.

The flywheel is machined from a chrome-moly blank forging as a single piece.   This means that the starter ring teeth are all part of the flywheel.  No worries about anything coming loose.  After machining, the flywheel is dynamically balanced then heat treated for strength and improved hardness on the wear surfaces.  ACT says it is safe to resurface this flywheel so it should have a long service life.  The flywheel is SFI certified, a very important safety item as well.

Look at the backside contour, there is no extra material to weigh this flywheel down.

While we had everything apart, we filled our transmission with Royal Purple’s Synchromax high performance synthetic manual transmission fluid, mostly because Eric swears by this stuff.  Synchromax is formulated to improve shifting and to reduce gear noise.  It is also designed for optimum lubrication and wear resistance while being compatible with synchros.  Royal Purple’s lubes form a bond to metal parts which prevents metal to metal contact.  From the smell we think this means that the oil has a high EP additive content as it reeks way more than standard gear oil!

We used Royal Purple synchromesh transmission fluid since Eric swears that this stuff is better than anything else.

With our engine nearly complete and a fresh drivetrain, our project Civic is that much closer to tearing it up.


M Factory




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