When you say that you “turn on” the ram air induction – do you have a flap or something?  Why turn it off?

Just curious,

Michael

Guys,

Yesterday I posted a message asking you IV-P builders for the benefit of your experience as I begin construction of my IV-P kit.  So, I thought it would only be fair if I post my thoughts as I reflect back on the construction and 7 ½ years of flying my 320.  I’m sure those still building would also appreciate more of you chiming in…

Would Definitely Do Again:

·         Forward CG.  Bias your weight and balance decisions toward a forward CG.  The airplane flies better here, the factory expanded the forward limit and you will end up having a useful capacity in your baggage area:

o   MKII tail and motor mount (the MKII motor mount moves the engine 3” forward)

o   Battery on the back of the firewall (vs. in the rear of the fuselage).  Also saves a significant run of heavy gauge wire to the rear.

o   Hydraulic pump to the back of the seat.  Also makes servicing the pump much easier

·         Constant speed prop –you will want this to accommodate the wide speed range of this wonderful little bird.  Improved, take-off and cruise performance.  Also, the heavier prop will help your CG picture.

·         Tim Ong shocks on the main gear.  Wouldn’t fly w/out them

·         Lightspeed Engineering electronic ignition in place of 1 of the magnetos.  I started w/ 2 mags and when one failed and needed replacement I switched to the Plasma III model of EI.  Best modification I’ve done so far.  I now run lean-of-peak, high altitudes (mid-teens), and burn about 10% less fuel at the same TAS as before the EI.  The fuel economy of this little bird is amazing!  (typical cruise 15,000’, WOT, 2300RPM, 5.8GPH, 182KTAS).

·         Fuel injected engine (see comments about lean of peak above)

·         Remove header fuel tank and wet the wings out to the tips.  I don’t like having a liquid bomb between me and the hot engine if I ever had to put it down off-field.  Also, the header tank is a variable weight item during a flight that is off the CG, effectively limiting your CG envelope.  Finally, fuel management of the header setup is an opportunity for pilot error or for transfer pumps to fail.

·         Make front deck (where header would have been) removable with piano hinges.  This makes instrument panel maintenance a piece of cake!

·         Forward hinge canopy

·         AOA system (Jim Frantz’s system, now I think Advanced Flight Systems).  Best safety device you can buy!!

·         Tim Ong’s landing lights on the main gear

·         Ram air for induction.  I get about 1” MAP boost when I turn it on.

·         Do not install passenger side rudder pedals (unless you want to give dual instruction).  They are extra weight, complexity, friction and cost.  Also, it is nice to have some space at the end of the passenger foot well for heavy items, an extra duffle bag or spare tire/tube.

·         TruTrak autopilot.  I have the DigiFlight IIVSGV and it is AWESOME!

Probably Would Do Differently:

·         Extended wing tips.  I live in Colorado and like to fly high.  Probably not the right answer for most people.

·         Use an IO-360 engine (I have an IO-320-D1B).  You can always throttle back for economy but it would be nice to have the extra 20hp for climb.

·         Use Grove wheels – I like their bearings much better than the Timken bearings in the Matcos.

·         Would probably install a modern EFIS system (Chelton or Garmin).  At the time I built, the 6-pack was the only thing I felt comfortable with as far as reliability for IFR.

Would Not Do Again:

·         “Smooth Prime” primer.  This stuff is water based and shrunk over time.  The result is that a year after painting the plane I started to see the fiberglass cloth weave in the reflections of the paint.  Especially bad in the hangar under fluorescent lights.

I hope this is helpful and motivating to those of you still building the 320/360.  Feel free to contact me offline for additional questions or clarifications.

Cheers!

Dan Olsen

Fort Collins, CO

N320DK – 550hrs