ENGINE WORK  December, 2008


Dec 1 - finished turning inside of supercharger pulley.  I'd specced it with walls much thicker than needed.  I'll have to see how much weight that removed.  1.0 hr

  Here is the supercharger pulley.  I don't have a "before" picture of the inside, but I put this in my lathe and removed a bunch of excess material from the inside.  The walls are still plenty thick, but I didn't want to cut any deeper and take a chance on making any of the walls too thin, just to save another gram or two.

Dec 4 - took machined SC pulley & bushing to supermarket & asked them to weigh it.   They now weigh 2.45 pounds.  Before trimming, the new one, with Trantorque bushing, weighed 3 pounds, 2 ounces.  The old one weighed 1 pound, 1/2 ounce.  So, I saved some weight by turning the inside of the pulley.  Probably about half of the weight of the new pulley comes from the big steel Trantorque bushing I need to hold it onto the supercharger.   Installed new pulley onto supercharger.  It took a lot of farting around, because the pulley moves axially as the Trantorque nut is tightened, causing the pulley to move up and bind against the supercharger housing as the nut is tightened.  It moved much more than what the Trantorque manual said it should, which told me the slightly undersize shaft was requiring too much tightening.  So, after many other attempts at positioning the pulley so it wouldn't end up binding against the SC housing, I wrapped the shaft with 0.005" feeler stock and torqued the nut up to 120 ft lb, with no excess axial movement and no binding.  1.5 hr

Dec 5 - reinstall supercharger & torque mount bolt to 75 in lb.  Loc-tite and torque crank pulley to 133 ft lb.  Work on layout hookup for throttle cable.   Wasted over an hour looking for my cable clamps & components from ACS.  Also spent time thinking about how very WRONG this whole supercharger installation is.  Measured Bowden cables for reaming cable clamps to fit.  2.0 hr

Dec 9 - drill Bowden cable clamps out to #B.  Since they're made for Bowden cables, I don't understand why they don't come from ACS with the correct inside diameter.  0.5 hr

Dec 10 - cut 1" out of supercharger belt tensioning rod and weld it back together.  1.0 hr

Dec 11 - start reinstalling the supercharger tubing and adjustment rod  1.0 hr

Dec 17 - fabricate & install spacer for throttle body.  Install & adjust TB end of throttle cable.  2.0 hr

Dec 21 - fiddled with supercharger adjusting rod quite awhile.  Finally gave up on Eggenfellner's hokey method and ordered parts from The Chassis Shop to make a proper belt tension adjusting rod with left- and right-handed threads.  Worked on setting up throttle cable, cable layout, quadrant layout.  Fabricated a bracket to hold an Adel clamp to the starter, for securing the throttle cable.   Installed LT EGT probe.  Worked on quadrant end of throttle cable.  Unfortunately, the cable I ordered is long enough, but it won't be after I cut about a foot off the end of it to make the end usable.  The higher quality (lined) cable only comes with a fixed rod on the end, and all I want is just the cable.   So, placed order with ACS for longer throttle and wastegate cables.  Calculated throttle cable mount point on quadrant for desired cable travel.  8.0 hr

Dec 24 - There is lots of talk on one of the Eggenfellner sites about more people having problems with poorly machined surfaces on the Eggenfellner intake manifolds. 

Dec 29 - received ACS order for new throttle cable parts

Dec 30 - received order from The Chassis Shop for parts to make supercharger belt tension adjusting rod.

Dec 31 - last chance to get some work done this year.  Lots of bad weather lately makes for little incentive to get out to the airport.  Worked at home on welding and machining  new brackets for throttle and wastegate cables going into throttle quadrant.  3.0 hr


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