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		kitfoxfugit(at)yahoo.com Guest
 
 
 
 
 
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				 Posted: Thu Jun 12, 2008 10:25 pm    Post subject: Engine and Performance Survey | 
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				Whurlybird asks:
 
 "What engine do you have mounted in what model Kitfox and how does your performance stack up?  Looking for GPH, cruise, climb, overall impression, the sorts of things you would tell your friend if he was talking about buying the same engine."
 
 Following are comments on my experience with the Rotax 912 UL, pros and cons.  Hope this helps.  Would like to see similar comments from users of other types.
 
 Model IV Speedster came with a Rotax 912 UL, with 500 hrs, has over 900 hrs on it now.  It is compact and light, supposedly weighs 132# with exhaust.
 
 It uses motorcycle oil in a dry sump, requiring it to be pulled through a certain way before startup to purge the cylinders and special knowledge and care in changing the oil to get it all out.  If overfilled, will puke out the extra.  Has an oil filter.  It is clean, leaks no oil, consumes no oil, keeps the same level from oil change to oil change.  Has coolant, calls for a special waterless kind but I use water and antifreeze.  Leaked a little for a while at one time.
 
 It burns 87 Octane car gas.  Alcohol is not a problem but it does not like lead, if burning 100LL, needs an additive.  Has dual electronic ignition.  Spark plugs are readily available and cheap, costing less than 1/10th the cost of aircraft plugs.
 
 It has 2 carbs that must be synchronized but are altitude-compensating and usually shake out carb ice.  It beat up one air cleaner against the firewall when they were mounted on the carbs and drew in air warmed by the exhaust.  Now has the carb heat box on it with a big air cleaner up front.  It has an enrichner "choke" that must be adjusted correctly and used a certain way on most, but not all, cold starts.
 
 It fires up instantly and smoothly, with instant oil pressure, but must be operated above 1800 RPM to avoid damage to the gearbox.  This can give thrust on landing without an adjustable prop.  It does not overheat (with an Ivoprop).  It runs smoothly and quietly, seems to have plenty of torque and power.  It has been extremely reliable and comforting over lots of wild country.
 
 Has a wide cruise range.  Can putt along at estimated 2 to 2 1/2 GPH, 65 MPH doors open or 75 doors shut.  Have not measured it exactly because do not fly it with full fuel when putting around, but can get 5 hours out of 12 gallons with some left.  Don't want much fuel in it when folding the wings.
 
 Experimenting with economy cruise, 4000 RPM 90 MPH, have not determined fuel burn.  Cruise for going places is 5000 RPM, 117 MPH, up to 5 GPH, about 20 MPG, plan on 300 miles, but can go 400 with a good hour's reserve. If bumpy, have to slow below 113.  Plane lacks gas cap fairings and strut fairings, has 6.00 x 6 tires, no wheel pants.
 
 Vapor locked one time I think, would not hot start after awaiting customs clearance after a long flight.  Had a broken exhaust once before I got it.  Has a weak alternator, need to economize on the electrical load and be sure battery is up to 14 volts before shutdown.  Battery needs some charge to excite alternator.
 
 Can be hand propped, but is dangerous as it starts up so fast.  Prop must not be turned backwards.
 
 Has instant throttle response, which can be a problem for the inexperienced on takeoff.  Has a vernier for small adjustments.  With springs, throttle defaults to full power when the linkage breaks, which it did on me once.  This is a good thing, unless you are taxiing through a crowd at an airshow.  Be sure to have good brakes.
 
 It requires special knowledge to operate and service.  The owner/operator must obtain the knowledge.  I do not think many A & P's are savvy to it yet.  Lockwood has a DVD and classes.
 
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		WurlyBird
 
  
  Joined: 16 May 2008 Posts: 207 Location: North Pole, Alaska
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				 Posted: Sun Jun 15, 2008 8:33 pm    Post subject: Re: Engine and Performance Survey | 
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				That is definitely a helpful testimonial.  I  would love to have that for a lot of engines.  One more question for you.  How much is an overhaul of a 912 supposed to normally cost, assuming no excessive wear or damage?
 
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  _________________ James
 
Kitfox 3 / 582 / 70" IVO 2 blade GA
 
50 hrs on the 582 swapping for HKS 700E and Avid Cowl. | 
			 
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		Lynn Matteson
 
 
  Joined: 10 Jan 2006 Posts: 2778 Location: Grass Lake, Michigan
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				 Posted: Sun Jun 29, 2008 5:34 am    Post subject: Engine and Performance Survey | 
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				I read John Allen's honest evaluation of his Rotax-powered Kitfox a  
 couple of weeks ago, and thought I'd respond with my experiences with  
 my Jabiru 2200-powered Kitfox.
 
 I inserted my comments after John's with the heading:  LM:  blah,  
 blah, blah.....
 
 Lynn Matteson
 Kitfox IV Speedster
 Jabiru 2200
 Status: flying w/541 hrs
 On Jun 13, 2008, at 2:22 AM, John Allen wrote:
 
  	  | Quote: | 	 		   
 
  Whurlybird asks:
 
  "What engine do you have mounted in what model Kitfox and how does  
  your performance stack up?  Looking for GPH, cruise, climb, overall  
  impression, the sorts of things you would tell your friend if he  
  was talking about buying the same engine."
 
  Following are comments on my experience with the Rotax 912 UL, pros  
  and cons.  Hope this helps.  Would like to see similar comments  
  from users of other types.
 
  Model IV Speedster came with a Rotax 912 UL, with 500 hrs, has over  
  900 hrs on it now.  It is compact and light, supposedly weighs 132#  
  with exhaust.
 
    LM:  Model IV Speedster kit had no engine...chose new Jabiru 2200;  
 | 	  
 has over 540 hours on it now.  Supposedly weighs 132 pounds  
 complete...and doesn't need radiator, coolant, or associated  cooling  
 hoses.
  	  | Quote: | 	 		   It uses motorcycle oil in a dry sump, requiring it to be pulled  
  through a certain way before startup to purge the cylinders and  
  special knowledge and care in changing the oil to get it all out.   
  If overfilled, will puke out the extra.  Has an oil filter.  It is  
  clean, leaks no oil, consumes no oil, keeps the same level from oil  
  change to oil change.  Has coolant, calls for a special waterless  
  kind but I use water and antifreeze.  Leaked a little for a while  
  at one time.
 
    LM:  Uses aviation oil in a typical aircraft engine wet sump.  
 | 	  
 Check oil with dipstick just like your car. Has an oil filter and  
 cooler, very minor leaks, but (mine) uses about 1 oz. per hour. No  
 coolant...uses air cooling principle, similar to most certified  
 airplane engines.
  	  | Quote: | 	 		   It burns 87 Octane car gas.  Alcohol is not a problem but it does  
  not like lead, if burning 100LL, needs an additive.  Has dual  
  electronic ignition.  Spark plugs are readily available and cheap,  
  costing less than 1/10th the cost of aircraft plugs.
 
    LM:  Requires 100LL for the first 50 hrs., then 93 octane if  
 | 	  
 desired. Jabiru does not recommend using an additive for 100LL....who  
 knows why? Dual electronic ignition, using common automotive spark  
 plugs...NGK D9EA. I have had problems with my distributor rotors  
 failing, but by following their instructions of gluing to rotors on  
 (huh?), I've had no recurrence of this problem. Dist caps and rotors  
 are common automotive units, but the shafts lay horizontally, and  
 this might be why Jabiru suggests gluing rotors onto the shafts. I  
 thought this was ridiculous, so the first time I felt it necessary to  
 change rotors and caps, I used my years of automotive knowledge and  
 ignored their advice....WRONG! Follow their advice and put your ego  
 on hold, Lynn.
  	  | Quote: | 	 		   It has 2 carbs that must be synchronized but are altitude- 
  compensating and usually shake out carb ice.  It beat up one air  
  cleaner against the firewall when they were mounted on the carbs  
  and drew in air warmed by the exhaust.  Now has the carb heat box  
  on it with a big air cleaner up front.  It has an enrichner "choke"  
  that must be adjusted correctly and used a certain way on most, but  
  not all, cold starts.
 
    LM:  Has one Bing carb, altitude compensating, carb heat box with  
 | 	  
 air cleaner. This carb is similar to the one used by Rotax, but size  
 may be different. The Jabiru likes to have a nice smooth tube  
 bringing air to the carb, with at least a 4" straight section just  
 before carb to prevent turbulence within the carb.
  	  | Quote: | 	 		   It fires up instantly and smoothly, with instant oil pressure, but  
  must be operated above 1800 RPM to avoid damage to the gearbox.   
  This can give thrust on landing without an adjustable prop.  It  
  does not overheat (with an Ivoprop).  It runs smoothly and quietly,  
  seems to have plenty of torque and power.  It has been extremely  
  reliable and comforting over lots of wild country.
 
    LM:  Starts instantly, instant oil pressure, and it is suggested  
 | 	  
 to run at 1200 rpm initially. Landing can be done at 900-950  
 rpm...suggested idle speed. No choice yet (that I'm aware of)  on  
 propellor choice. Must use wood so far as I know...(adjustable prop  
 by Sensenich is in the testing phase)
 I think that Rotax had the edge on torque and power, due to their  
 gearbox and high-revving engine, and use of 3-bladed props. But I  
 like the Jabiru philosophy of low rpm, direct-drive, simple  
 mechanics, like most certified airplane engines.
  	  | Quote: | 	 		   Has a wide cruise range.  Can putt along at estimated 2 to 2 1/2  
  GPH, 65 MPH doors open or 75 doors shut.  Have not measured it  
  exactly because do not fly it with full fuel when putting around,  
  but can get 5 hours out of 12 gallons with some left.  Don't want  
  much fuel in it when folding the wings.
 
    LM:  I can cruise from 90-105mph, using 3.8-4.1 gallons per hour,  
 | 	  
 based on how I fly my plane. I once flew a couple of back-to-back 513- 
 mile tanks, and have never put in more than 23 gallons after doing  
 so. It can climb from 1200 fpm, down to 3-400 fpm, depending on  
 conditions. Leaving Cochise Co. airport in Arizona (4186' elev.) with  
 full tanks (27 gallons) , it took me 10 minutes to climb an  
 additional 4500 feet, on a hot day with high (don't recall) density  
 altitude.
  	  | Quote: | 	 		   Experimenting with economy cruise, 4000 RPM 90 MPH, have not  
  determined fuel burn.  Cruise for going places is 5000 RPM, 117  
  MPH, up to 5 GPH, about 20 MPG, plan on 300 miles, but can go 400  
  with a good hour's reserve. If bumpy, have to slow below 113.   
  Plane lacks gas cap fairings and strut fairings, has 6.00 x 6  
  tires, no wheel pants.
 
    LM:  Have not experimented with economy fuel burn...too  
 | 	  
 boring. : )  I cruise at Jabiru's suggested 2750-2950 rpm  
 (redline=3300 rpm) 90-105mph...on last year's California trip, speed  
 was 98.4mph average, coming and going (6161 statute miles total) (at)  
 3.93gallons/hour average. Fuel burn on entire trip was 246.03  
 gallons, costing $1004.23....ain't gonna happen that cheap any time  
 soon! ($4.08/gallon avg. across the country)
 
    Oh, I almost forgot...last year I flew as slow as the slowest C150  
 on a trip east, and averaged 3.69 gal./hr. Another average shows 3.42/ 
 hr, but I can't recall the flying conditions, or how long the trip was.
 
  	  | Quote: | 	 		   Vapor locked one time I think, would not hot start after awaiting  
  customs clearance after a long flight.  Had a broken exhaust once  
  before I got it.  Has a weak alternator, need to economize on the  
  electrical load and be sure battery is up to 14 volts before  
  shutdown.  Battery needs some charge to excite alternator.
 
    LM:  I had one embarrassing incident at Oshkosh last year where  
 | 	  
 the engine did not start after taxiing for almost a mile, shutting it  
 down, and forgetting to shut off main fuel supply and engine flooded.  
 Too much cranking before realizing it was flooded caused battery to  
 go dead. Charging battery fixed it. My engine outputs 10 amps, so I  
 keep use of battery-powered devices to below 10 amps...later engines  
 have higher output from alternator.
  	  | Quote: | 	 		   Can be hand propped, but is dangerous as it starts up so fast.   
  Prop must not be turned backwards.
    LM: Jabirus cannot be hand propped (unless after-market ignition  
 | 	  
 system is installed), but prop can be turned in either direction  
 without consequence.
 
  	  | Quote: | 	 		  
  Has instant throttle response, which can be a problem for the  
  inexperienced on takeoff.  Has a vernier for small adjustments.   
  With springs, throttle defaults to full power when the linkage  
  breaks, which it did on me once.  This is a good thing, unless you  
  are taxiing through a crowd at an airshow.  Be sure to have good  
  brakes.
 
    LM: My Jabiru also has instant throttle response, but the  
 | 	  
 instructions call for a slow push on throttle for best result. I  
 tweaked my carb to get instant response. Similar Bing carb, so spring  
 defaults to full throttle...spring can be removed, but this is not  
 good if you are flying and linkage breaks and you want to get home.  
 Better to have throttle go wide open and control speed with mag switch.
 
  	  | Quote: | 	 		   It requires special knowledge to operate and service.  The owner/ 
  operator must obtain the knowledge.  I do not think many A & P's  
  are savvy to it yet.  Lockwood has a DVD and classes.
 
    LM: No particular special knowledge required for the Jabiru. No  
 | 	  
 special precautions about rotating prop, no special precautions about  
 checking oil, no special coolants required...pretty much standard  
 engine knowledge will get you through.
 
  |  | - The Matronics Kitfox-List Email Forum - |  |   |  Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
 
  http://www.matronics.com/Navigator?Kitfox-List |  
  |  
 
 
 
 
  _________________ Lynn
 
Kitfox IV-Jabiru 2200
 
N369LM | 
			 
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		Fox5flyer Guest
 
 
 
 
 
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				 Posted: Sun Jun 29, 2008 2:49 pm    Post subject: Engine and Performance Survey | 
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				DM:  Great-pure fact-report guys.   Excellent.  I'll add mine because there are quite a few Subaru powered  Foxes on this list and someone might be interested.
  First, it's a 100hp EA81 normally aspirated  Subaru with NSI conversion mounted on a S5 Kitfox.  The Dyno graph that  came with it indicated 112hp, but I have no idea which is correct.  The  manager of NSI is no longer around and the company was reclaimed by the owner  (Maxwell) who stopped production of the EA81 package preferring to only produce  the larger, higher hp, and heavier Soobs like the EJ22, 25, etc. which  sort of makes me an orphan for factory support.  However, most of the  engine parts are standard off the shelf.   For a reduction unit it  uses a very robust  NSI produced gear drive using a sprag clutch that  works very well.  However, it also is no longer factory supported and  getting parts for it will be a much bigger challenge, especially  as time goes on.  All ancillary parts like motor mount, radiator, etc were  very well made.
  see below...
   
   
  From: Lynn  Matteson <lynnmatt(at)jps.net>
 Sent: Sunday, June 29, 2008 8:32:06  AM
 Subject: Re: Engine and Performance Survey
 -->  Kitfox-List message posted by: Lynn Matteson <lynnmatt(at)jps.net (lynnmatt(at)jps.net)>
 
 I read John Allen's honest evaluation  of his Rotax-powered Kitfox a  
 couple of weeks ago, and thought I'd  respond with my experiences with  
 my Jabiru 2200-powered  Kitfox.
 
 I inserted my comments after John's with the heading:   LM:  blah,  
 blah, blah.....
 
 Lynn Matteson
 Kitfox IV  Speedster
 Jabiru 2200
 Status: flying w/541 hrs
 On Jun 13, 2008,  at 2:22 AM, John Allen wrote:
 
  	  | Quote: | 	 		   --> Kitfox-List message posted by:  John Allen <kitfoxfugit(at)yahoo.com (kitfoxfugit(at)yahoo.com)>
 
  Whurlybird asks:
 
  "What engine do you  have mounted in what model Kitfox and how does  
  your performance  stack up?  Looking for GPH, cruise, climb, overall  
   impression, the sorts of things you would tell your friend if he  
   was talking about buying the same engine."
 
  Following are  comments on my experience with the Rotax 912 UL, pros  
  and  cons.  Hope this helps.  Would like to see similar comments   
  from users of other types.
 
  Model IV Speedster came with  a Rotax 912 UL, with 500 hrs, has over  
  900 hrs on it now.   It is compact and light, supposedly weighs 132#  
  with  exhaust.
 
   LM:  Model IV Speedster kit had no  engine...chose new Jabiru 2200;  
 | 	  
 has over 540 hours on it now.   Supposedly weighs 132 pounds  
 complete...and doesn't need radiator,  coolant, or associated  cooling  
 hoses.
   
  DM:   The NSI package is, compared to Jab and 912, heavy as are most  Subarus.  Mine, with motor mount, hoses, radiator, and everything it takes  to make it run was 232 pounds.  I know this because I weighed it  myself on a large platform scale.  This requires balance considerations and  I chose to mount a 28amp AGM battery in the back and use a large Maule Tundra  tailwheel with 2" extended spring.  No further weight was needed in the  tail.  It's very difficult to build a light Kitfox using any Subaru, yet  it's an option that can be considered.
  
  	  | Quote: | 	 		   It uses motorcycle oil in a dry sump, requiring it to be  pulled  
  through a certain way before startup to purge the  cylinders and  
  special knowledge and care in changing the oil to  get it all out.  
  If overfilled, will puke out the extra.  Has  an oil filter.  It is  
  clean, leaks no oil, consumes no oil,  keeps the same level from oil  
  change to oil change.  Has  coolant, calls for a special waterless  
  kind but I use water and  antifreeze.  Leaked a little for a while  
  at one  time.
 
   LM:  Uses aviation oil in a typical aircraft engine  wet sump.  
 | 	  
 Check oil with dipstick just like your car. Has an oil  filter and  
 cooler, very minor leaks, but (mine) uses about 1 oz. per  hour. No  
 coolant...uses air cooling principle, similar to most  certified  
 airplane engines.
   
  DM:  Uses any normal automotive oil.   I use Castrol GTX 20w50 and a NAPA filter and it needs no oil cooler for  cooling.  No engine leaks after 377+ hours, however it uses about a pint  over 20 hours.  Requires normal automotive coolant for aluminum  engines.  Changing oil is very simple.
 
 
  	  | Quote: | 	 		   It burns  87 Octane car gas.  Alcohol is not a problem but it does  
  not  like lead, if burning 100LL, needs an additive.  Has dual  
   electronic ignition.  Spark plugs are readily available and cheap,   
  costing less than 1/10th the cost of aircraft plugs.
 
    LM:  Requires 100LL for the first 50 hrs., then 93 octane if   
 | 	  
 desired. Jabiru does not recommend using an additive for 100LL....who   
 knows why? Dual electronic ignition, using common automotive spark   
 plugs...NGK D9EA. I have had problems with my distributor rotors   
 failing, but by following their instructions of gluing to rotors on   
 (huh?), I've had no recurrence of this problem. Dist caps and rotors   
 are common automotive units, but the shafts lay horizontally, and   
 this might be why Jabiru suggests gluing rotors onto the shafts. I   
 thought this was ridiculous, so the first time I felt it necessary to   
 change rotors and caps, I used my years of automotive knowledge and   
 ignored their advice....WRONG! Follow their advice and put your ego   
 on hold, Lynn.
   
  DM:  Will burn pretty much any gas, but  the compression is bumped up a bit so I use premium.  I don't know if  alcohol is being used in my area, but if it is I've seen no performance or  economy differences.  It uses dual electronic ignitions by Electromotive,  but they go through coil joiners to a single standard spark plug per  cylinder.  One of my coil joiners went bad where I would get a miss, but  the airplane was still flyable and it was a simple replacement.   
  	  | Quote: | 	 		   It has 2 carbs that must be synchronized but are  altitude- 
  compensating and usually shake out carb ice.  It beat up  one air  
  cleaner against the firewall when they were mounted on  the carbs  
  and drew in air warmed by the exhaust.  Now has  the carb heat box  
  on it with a big air cleaner up front.  It  has an enrichner "choke"  
  that must be adjusted correctly and used  a certain way on most, but  
  not all, cold  starts.
 
   LM:  Has one Bing carb, altitude compensating,  carb heat box with  
 | 	  
 air cleaner. This carb is similar to the one used  by Rotax, but size  
 may be different. The Jabiru likes to have a nice  smooth tube  
 bringing air to the carb, with at least a 4" straight  section just  
 before carb to prevent turbulence within the carb.
   
  DM:  The NSI Soob has one Ellison throttle  body fuel injector that requires a fuel pump for takeoff, but not cruise.   Very simple and works well and on the plus side you can talk on the phone to the  guy who builds it.  Has carb heat, but never needed it.  Also has the  capability to lean just like an O200 so one can set it up for good  economy.  It can be a bit of a problem starting in cold weather (below 30f)  due to a very light flywheel and the type of ignition modules it uses.  IMO  this is it's weakest trait.  Different ignition modules would probably cure  the problem.
  
  	  | Quote: | 	 		   It fires up instantly and smoothly, with instant oil pressure,  but  
  must be operated above 1800 RPM to avoid damage to the  gearbox.  
  This can give thrust on landing without an adjustable  prop.  It  
  does not overheat (with an Ivoprop).  It runs  smoothly and quietly,  
  seems to have plenty of torque and  power.  It has been extremely  
  reliable and comforting over  lots of wild country.
 
   LM:  Starts instantly, instant oil  pressure, and it is suggested  
 | 	  
 to run at 1200 rpm initially. Landing  can be done at 900-950  
 rpm...suggested idle speed. No choice yet (that  I'm aware of)  on  
 propellor choice. Must use wood so far as I  know...(adjustable prop  
 by Sensenich is in the testing phase)
 I  think that Rotax had the edge on torque and power, due to their   
 gearbox and high-revving engine, and use of 3-bladed props. But I   
 like the Jabiru philosophy of low rpm, direct-drive, simple   
 mechanics, like most certified airplane engines.
   
  DM:  Starts right up in decent weather,  but not cold--see above.  Idles at 2000rpm to minimize tortional pulses  from the prop, but can be idled down briefly to 1400 for landing.  Takeoff  rpm is about 5400.   Again, this is a heavy package with the S5  already being much heavier than the IV, but the higher wing loading gives a  slightly smoother ride in the bumps.
 
 
  	  | Quote: | 	 		   Has a wide  cruise range.  Can putt along at estimated 2 to 2 1/2  
  GPH,  65 MPH doors open or 75 doors shut.  Have not measured it  
   exactly because do not fly it with full fuel when putting around,  
   but can get 5 hours out of 12 gallons with some left.  Don't want   
  much fuel in it when folding the wings.
 
   LM:  I  can cruise from 90-105mph, using 3.8-4.1 gallons per hour,  
 | 	  
 based on  how I fly my plane. I once flew a couple of back-to-back 513- 
 mile tanks,  and have never put in more than 23 gallons after doing  
 so. It can  climb from 1200 fpm, down to 3-400 fpm, depending on  
 conditions.  Leaving Cochise Co. airport in Arizona (4186' elev.) with  
 full tanks  (27 gallons) , it took me 10 minutes to climb an  
 additional 4500 feet,  on a hot day with high (don't recall) density  
 altitude.
   
  DM:  Can cruise from 75 to 110mph.   Economy cruise where I primary keep it is about 105mph at 3.8gph.  I don't  know how fast it will go because I've never attempted it, but it will easily  cruise 115, but at the expense of higher fuel burn.  Climbout is anywhere  between 750 on a hot day to 1200 on a cool day with good conditions.  These  numbers change with weight, obviously. but my numbers are with full tanks and  just me at 175lbs and nearly sea level.  I've never cruised any higher than  7.5, but never needed to either.  Endurance would be about the same as the  Jab or 912.
  
 
  	  | Quote: | 	 		   Experimenting with economy cruise, 4000 RPM 90 MPH, have  not  
  determined fuel burn.  Cruise for going places is 5000  RPM, 117  
  MPH, up to 5 GPH, about 20 MPG, plan on 300 miles, but  can go 400  
  with a good hour's reserve. If bumpy, have to slow  below 113.  
  Plane lacks gas cap fairings and strut fairings, has  6.00 x 6  
  tires, no wheel pants.
 
   LM:  Have  not experimented with economy fuel burn...too  
 | 	  
 boring. : )  I  cruise at Jabiru's suggested 2750-2950 rpm  
 (redline=3300 rpm)  90-105mph...on last year's California trip, speed  
 was 98.4mph average,  coming and going (6161 statute miles total) (at)  
 3.93gallons/hour  average. Fuel burn on entire trip was 246.03  
 gallons, costing  $1004.23....ain't gonna happen that cheap any time  
 soon! ($4.08/gallon  avg. across the country)
   
  DM:  I always economy cruise because  I'm cheap.  Generally at about 3900rpm, 22"mp, and about 105mph or a  little faster with 3.8 to 4gph fuel burn.  Part of the good cruise speed is  due to the NSI electric pitch prop (more below) and lots of fairings  including wheel pants.  My strip is grass and relatively short, but there  are no problems with either takeoff or landing  performance.
 
   Oh, I almost forgot...last year I flew as  slow as the slowest C150  
 on a trip east, and averaged 3.69 gal./hr.  Another average shows 3.42/ 
 hr, but I can't recall the flying conditions, or  how long the trip was.
 
  	  | Quote: | 	 		   Vapor locked one time I think, would not hot  start after awaiting  
  customs clearance after a long flight.   Had a broken exhaust once  
  before I got it.  Has a weak  alternator, need to economize on the  
  electrical load and be sure  battery is up to 14 volts before  
  shutdown.  Battery needs  some charge to excite alternator.
 
   LM:  I had one  embarrassing incident at Oshkosh last year where  
 | 	  
 the engine did not  start after taxiing for almost a mile, shutting it  
 down, and  forgetting to shut off main fuel supply and engine flooded.  
 Too much  cranking before realizing it was flooded caused battery to  
 go dead.  Charging battery fixed it. My engine outputs 10 amps, so I  
 keep use of  battery-powered devices to below 10 amps...later engines  
 have higher  output from alternator.
   
  DM:  As with most engines, the Soob can  also have vapor lock problems if left in hot sun with hot engine and attempting  to start after about 30 minutes of heat soak.  It always starts though,  just not very quick.  I usually try to point it into the breeze and open  the oil inspection door open.  It needs a good quality fuel valve because  the fuel needs to be shut down to kill the engine and left off until restart,  per manufacturer's instructions.  Good 50amp Nippon Denso alternator.   
 
 
  	  | Quote: | 	 		   Can be hand propped, but is dangerous as it starts  up so fast.  
  Prop must not be turned backwards.
   LM:  Jabirus cannot be hand propped (unless after-market ignition  
 | 	  
 system is  installed), but prop can be turned in either direction  
 without  consequence.
   
  DM:  Due to the sprag clutch in the prop, it cannot be hand  propped.  It will just freewheel spin.  The prop is an electrically  cockpit adjustable (CAP) and works great.  I pitch for max performance  takeoff and after 500 feet I add pitch for cruise climb and when reaching  altitude add more pitch for cruise then set up throttle, mixture, and  pitch for best mp and cruise economy.  The prop adds some complexity,  but well worth it and once it's gotten used to becomes second nature.   Again, the prop is no longer factory supported so some day I may have a problem  finding parts.
  
 
  	  | Quote: | 	 		  
  Has instant throttle response, which can be a problem  for the  
  inexperienced on takeoff.  Has a vernier for small  adjustments.  
  With springs, throttle defaults to full power when  the linkage  
  breaks, which it did on me once.  This is a good  thing, unless you  
  are taxiing through a crowd at an  airshow.  Be sure to have good  
  brakes.
 
   LM:  My Jabiru also has instant throttle response, but the  
 | 	  
 instructions  call for a slow push on throttle for best result. I  
 tweaked my carb to  get instant response. Similar Bing carb, so spring  
 defaults to full  throttle...spring can be removed, but this is not  
 good if you are  flying and linkage breaks and you want to get home.  
 Better to have  throttle go wide open and control speed with mag switch.
   
  DM:   My throttle response is good  throughout its range and I operate it much like the Jabiru mainly to be easy on  the engine.  
  Overall, it's a good package and gives good  service.  Subarus are known for their rugged reliability which is a plus,  but each different engine builder sets them up differently so it's difficult to  compare.  Stratus has a good rep.  
  However, I probably wouldn't do it again, even  if NSI was still supporting it.  I would probably go with the ubiquitous  and simple O200, or possibly a 912S if I could find one for the right  price.  I would definitely go for the extra bucks and get a cockpit  adjustable prop.  
  If money is a big issue, the Subaru can be a  good choice, but lacks the "big factory" type support.  Many people convert  their own.
   
  Deke Morisse
 Mikado Michigan
 S5/Subaru/CAP  377+ TT
 "The aim of an argument or discussion should not be victory, but  progress."
 - Joseph Joubert
   
  
  
   
   
  
  
    [quote][b]
 
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