Original Posted By: Ian Holland
Subject: Pietenpol-List: FW: Corvair Fishing>I've located a shop that has an after market distributer kit. It includes>heavier weights and three sets of springs, Light medium, heavy for the>corvair distributer. They could not tell me which of the sets would open to>full advance @ 2000 RPM. Does anbody know what tension of spring should be>used for this application? The specs I've found in al the corvairliterature>are all the same.>>Domenic> ---------->From: jmcnarry(at)techplus.com>To: Pietenpol Discussion>Subject: Re: Corvair Fishing>Date: Monday, May 10, 1999 8:06PM>>Domenic> You could set the timing plate in a locked position so that the vacuum>advance is inoperative the vac advance is only used on cars at partthrottle>for economy cruising at a lean mixture. The static timing (retarded) should>be as the corvair to ensure easy starting. The springs need to be only>strong enough to return it to statc timing at low power settings. The max>advance can be limited or changed by the pins or slots that the weightsmove>in.( alittle welding a little filing) If you can find advance curvediagrams>for a corvair at peak torque speed set the max for that. The timing won't>need to change once you have it started and the throttle set for enough>power to keep it in the air. Aircraft mags dont have advance curves just an>impulse on one mag for starting.>John Mc> -----Original Message----->From: BELLISSIMO, DOMENIC >To: Pietenpol Discussion >Date: Monday, May 10, 1999 12:41 PM>Subject: Corvair Fishing>>>>To All Flying Corvair Piet. owners,>>My current Stats:>>Engine static = 2600 RPM>>@ Full throttle in Cruise + 2600 RPM>>aircraft weight and balance is well within the envelope.>>Aircraft empty weight = 807 Lbs.>>Aircraft engine feels like it is flying with a governor on it.>>My Problem: It flies slightly tail low or in a nose high attitude like it>is>>underpowered, or you were flying in slow flight. My clinb to 800 ft.>circuit>>altitude above the ground was slow.>>timing: currently set for 14 deg. BTDC with the vacumm advance wired inone>>position. But I don't know which posion is full on or full off right now.>>The engine starts easy. I have a starter installed.>>Propeller: Home made 66X32>>This week-end the intake including the 'Y' split before the runners to the>>intake boss was replaced. The result was ...no change. Not even 1 RPM>>difference. There could only be 1 of four problems or a combination. 1.>>Fuel 2. intake system 3. Propeller 4. Timing.>>I'M next going to illiminate Timing.>>>>So here are the questions:>>>>What did y'all do to the distributer, ie weights, springs, vacuum advance>>Plate?>>Some of the literature I've read said to change the springs to 1960 model>>year, but when I looked up the specs... they were exactly the same tension>>rating.>>Should the weights be welded to full advance or otherwise.>>In what position did you lock the vacuum advance?>>What timing was it set at idle?>>What should it be at full throttle/static?>>Should I expect any improvement with timing changes?>>What RPM are y' all achieving and with what prop. pitch?>>I would appreciate your knowledgable response as soon as posible.>>Stuck with "aircraft on ground",>>Domenic>>>________________________________________________________________________________