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RV's are designed by Van Aircraft, Inc with Lycoming engines in mind.  Vans Aircraft, Inc. recommends putting a Lycoming in your RV.  On the other side of the coin, there are several RVs flying today using alternative power sources.  What I'm hoping to do with this section is present power alternatives to potential and current RV builders in an unbiased fashion.  It is my hope that in the end we will have a better informed RV community and better, more dependable engines.  dr

Words/News/etc.
  • Larry Vetterman Flight Tests (5) Different Exhaust Pipe Configurations On His RV

     

  • Assembling an ECI O-360 kit Engine
    ...from Tim Ribble.  Step by step - all in pictures.  Absolutely a MUST SEE article.  BTW, this is the same engine I have in Flash.
     
     related: www.ECI2fly.com | Traditional Engines section of the forums

     

  • Exhaust Study Results: Aerospace Welding Minneapolis, Inc.
    ...submitted by John L. Hole (employee of Aerospace Welding Minneapolis)

    We are frequently ask for valid, independent test results on the performance of exhaust systems for RV aircraft and with so many requests, it appears that it is of general interest to RV builders and owners.

    We believe the best information is found in a 16-month study conducted by the CAFÉ Foundation. It can be found there as a .pdf - http://cafefoundation.org/v2/research_reports.php the first study on the list should be the exhaust study.

    Some portions in that study relate to Aerospace Welding Minneapolis, Inc., as manufactures of
    4 INTO 1 systems, appear on #9 and #10:

    “Aerospace Welders in Minneapolis, Minnesota can provide very high quality stainless steel collectors and merges for any desired system. All systems must include slip joints or ball joints for strain relief placed both at the mouth of the collector entry as well as about half way down the headers The joints must always be secured with redundant spanning bolts, compression springs and cotter pinned castle nuts.”

    The study conclusions state, in part:

    1. Substantial negative pressure waves can be generated in tuned aircraft exhaust systems and the timing of their suction can be arranged so as to improve engine power. Such improvement should produce more power, better efficiency and a cleaner combustion chamber.
    2. The 4 into 1 collector exhaust systems appear to offer the best combination of low opening pressure, some pumping gain and good scavenging, though the crossover and Tri-Y systems can also obtain good scavenging during the overlap stroke.
    3. The addition of a suitable megaphone to the collector of a 4 into 1 exhaust system usually produces an increase in the negative pressure achieved at the exhaust valve, but at a substantial penalty in noise.
    4. The use of swiveling ball joints on the collector of a 4 into 1 exhaust system has a neglible effect on the EPG and provides an important vibration-isolation benefit to the system.
    5. The optimization of pipe geometry for the crossover, Tri-Y and 4 into 1 exhaust systems can be found by study of the EPG.

    We hope this information is helpful and invite you to call 800-597-4315 with any questions.
    fmi: http://www.awi-ami.com

     

  • Results of (3) Exhaust System Tests
    ...by RV exhaust guru Larry Vetterman

    RESULTS OF EXHAUST SYSTEM TESTS (January '07)
    I decided to conduct a comparative test of three different types of exhaust systems available for the RV’s. The 4 into 1 collector system, the standard crossover system and the 4 pipe system. Each of these systems had previously been installed and flown a minimum of 50 hours on my RV-7A. Each one of these systems are considered standard exhausts for the RV’s.

    The tests were conducted using the Flight Data System (APF 30) in the aircraft. It was my goal to measure True Airspeed, fuel burn, EGT’s, gallons per hour, percent HP, and also monitor engine smoothness with each system. It was assumed that any instrument error would be the same for each system so it was not a concern. It was not a goal to measure the different sounds or noise levels that each system produced. The results on the RV-7A, I0-360 M1B engine, 265 hrs.total time, with ECI Titan cylinders are as follows. All flights were at 8000 ft. density altitude (taken from the Flight Data System) and full throttle

    System 1: 4 into 1 collector This system required cutting a hole in the bottom cowl and bringing it out beside the nose gear. I then spent a number hours fabricating a fairing around the collector and tail pipe. I wanted a smooth fairing to get all the speed that I could.

    Density Altitude 8000 ft. OAT 23.0 F. RPM 2400 MP 21.9in.
    EGT’s #1 1270 #2 1340 #3 1277 @4 1308
    IAS 179MPH TAS 202MPH GPH 10.0GPH 71% power
    Note This RPM produced a rough engine.

    RPM 2500 MP 21.9
    EGT’s #1 1263 #2 1322 #3 1265 #4 1298
    IAS 182MPH TAS 206MPH GPH 10.6 73% power
    Note The engine was smooth at this RPM

    RPM 2600 MP 21.9
    EGT’s #1 1265 #2 1325 #3 1271 #4 1294
    IAS 186MPH TAS 210MPH GPH 10.9 76% power
    Note The engine was very smooth at this RPM

    System 2: Standard crossover for the M1B engine. No cowl modifications required.

    Density Altitude 8000 ft. OAT 8.4 F RPM 2400 MP 21.3 in.
    EGT’s #1 1294 #2 1293 #3 1249 #4 1255
    IAS 180 MPH TAS 202 MPH GPH 9.4 70% power
    Note: The OAT was somewhat lower than in Test #1. Engine was smooth at the RPM.

    RPM 2500 MP 21.3
    EGT’s #1 1305 #2 1291 #3 1250 #4 1250
    IAS 182 MPH TAS 204 MPH GPH 10.2 72% power
    Note The engine was smooth at this RPM

    RPM 2600 MP 21.3
    EGT’s #1 1309 #2 1292 #3 1260 #4 1256
    IAS 184 MPH TAS 208 MPH GPH 10.7 75% power
    Note The engine was smooth at this RPM. The flight data system oscillated between 208 and 209 MPH so I used the lower number.

    System 3: 4 pipe exhaust. No cowl modifications required.

    Density Altitude 8000 ft. OAT 32.7F. RPM 2400 MP 22.4
    EGT;s #1 1315 #2 1303 #3 1299 #4 1265
    IAS 178 MPH TAS 202 MPH GPH 9.8 71% power
    Note The engine was smooth at this RPM

    2500 RPM MP 22.4
    EGT’s #1 1315 #2 1303 #3 1299 #4 1266
    IAS 183 MPH TAS 206 MPH GPH 10.4 74% power
    Note The engine was smooth at this RPM

    2600 RPM MP 22.3
    EGT’s #1 1308 #2 1296 #3 1282 #4 1258
    IAS 186 MPH TAS 210 MPH GPH 10.9 76% power
    Note The engine was smooth at this RPM

    The outcome of this test is somewhat in line of my thinking that most exhaust systems will perform about the same at power settings at or below 75%. Fuel burn may vary according to wx conditions and leaning techniques. My assumption is the variance in manifold pressures that were indicated are due to the different OAT’s. Differences in EGT readings may be due to variations in probe locations on each system ie. The actual distance of the probes from the exhaust port.

    The factory literature for the 7A shows the top speed is 210 MPH and this test is in line with that speed. We all want to go faster, but in reality a couple more MPH’s are hard to obtain and the answer may not be in the exhaust system alone but a combination of factors. I hope this test will help in selecting the right system for your aircraft- engine combination.

    One test that I also conducted was to bring the throttle to idle during approach and landing to see if any of the systems would backfire and pop. I could not get any of the systems to do it as the fuel injection system (idle mixture) is set properly and there are no induction leaks on this engine.

    Larry Vetterman , Vetterman Exhaust Inc. (vetxaust at gwtc.net)
    related:
    Vetterman's section in Van's online store

      
       [ed. Flash uses one of Larry's 2" crossover system. dr]

       related: Traditional engines section of the VAF Forums


     

  • Vetterman Exhaust Introduce Muffler Systems for RVs
    ...from Larry Vetterman
      "Introducing new system as shipped to Vans Aircraft with 2" pipes 2" standard heat muff.  If you want mufflers contact us and you can send your 2" pipes back and we'll send you mufflers.  Currently available on the O-320 and O-360 engines on the following RVs (6/6a/7/7a/8/9/9a (no 8a))
      Call Larry Vetterman 605.745.5932  for pricing and other questions."
     

  • EIS User-Definable Pages
    ...sent in by Mike Schipper
    "Since I obviously had way too much free time this past weekend, I put together this interactive editor for setting up the user-definable pages on the EIS.  You still have to key in the data, but at least this is an easy way to experiment with many different layouts ahead of time.
    http://www.my9a.com/eis/
    Let me know what you think.
    Mike Schipper
    www.my9a.com

     

  • Vetterman Exhaust RV-10 Exhaust System

       Play This Audio Clip: 1min 44sec (166KB)
     

  • Oil Door
    ...sent in by Tony Partain [tpartain 'at' bendbroadband.com]
       I have a custom oil door with a hidden latch and hidden hinge system on my RV7. This is the most trick unit I have ever seen. As you can see from the pictures the fit is comparable to a custom hot rod shop! All of the aluminum parts are extruded for a very nice fit and finish. This can be purchased thru Aviax Inc advancedaviationinc.com. This is the shop that is assisting me with my plane. They have been building kit planes for about 12 years. Everything from Rans, RV's and Lancairs.
    The owner is Mike Custard. He working on several mods for the RV series. His email is mike'at'advancedaviationinc.com . Phone 541-330-5817
     Tony Partain
     Partain Transport Company (web)
     2512 NW Ordway Ave
     Bend OR 97701
     800-774-0828 watts

     

  • Turbine Thoughts From Danny King
    From: Danny King [mailto:danny.king 'at charter.net]
    ...this was kicked around in the 8 yahoo group. This is Danny's response.

    "Can you imagine cruising along in your RV burning 30 gallons an hour?"

    30 gallons an hour......OMG!

    I like the idea of a light turbine, but at today's fuel cost, it doesn't make much sense for RV pilots. I just finished a 3,000+ mile round-robin in the Doll, and I was able to get a feel for the Extended Range Tanks form Hotel Whiskey aviation, sold through Safe-Air 1. I am really pleased!

    I launched for Northern Indiana to help an RV-8 building legend, original "Short lister", and host of the yearly Oshkosh RV meetings at the theater in the woods...Don Mc Namara (N8RV) (can you believe he has that N number?) The distance from my home airport to his was just under 900 statute miles. I launched with 52 gallons on board. Three hours and 50 minutes later, I landed at Don's airport with 1 hour and 23 minutes endurance remaining! Nice tailwind!

    After a great week of RV work, and being wined and dinned by Don and his lovely wife Melinda, I started off on leg two. It was a clear and cool morning in Indiana as I flew nearly due south toward Naples, Florida and the Wing South flying community. The GPS said 1,100 statute miles.

    After established in cruise I pressed the fuel reserve button on my Electronics International fuel computer, and it said 0 with the fuel low warning light on. It uses GPS data, and will give either a plus or minus number for fuel remaining, and a low fuel warning for an hour or less endurance at destination. I had lied to the computer when I entered the fuel on board by one gallon. I entered 52 but actually had 53 gallons on board. I was amazed. On that day, I theoretically could have made a Space Shuttle One arrival at Wing South airport in Naples Florida 1,100 miles away!

    It was also 1,100 miles from Wing South to my home field (52F). The trip was almost a perfect triangle. The leg home included a three day stop at Sun-N-Fun which is 140 miles north of Naples. The flight down Destin beach in the military corridor was beautiful. A couple of F-15 Eagles took off and flew right over me. The controller called each of us as traffic for the other and we had a visual on each other. I guess the fighter boys wanted a better look at my RV-8. I loved the great look I got of the Eagles.

    I found as much as a dollar a gallon difference in 100LL prices, and on the return flight, I used the Aux tanks to get to an airport with cheaper fuel. I filled them back up again to take advantage of the price. That's another advantage of the extended range tanks.

    The Doll has an I0360A1B6. Takeoff fuel flow can exceed 15 GPH, but cruise is below 10 GPH and at 10,000 it is below 9 GPH. On the flight out to Van's homecoming last September on Doug Reeves wing, I was burning 8.3 GPH and burned around 5 gallons less than Doug's 160hp 0320 FP each leg (now a 180hp C/S setup).

    Considering the great performance the Doll has with the 200 hp Lycosorus, I think I'll pass on the turbine upgrade!

    Danny King
    Beautiful Doll 80434
     

  • (3/29/05) Rotary Powered N19VX Flies 1 Hour Today (its first hour)
    ...sent to me by Bernie Kerr (jbker 'at' juno.com)

       Beautiful weather this morning. 60 degrees , dry , light wind. Took 2 good data points I think. If the data holds up tonight when I scrub it, it appears that I am flowing a lot more air by the radiator than the lycoming puts over the fins. If that is true, than you would think the radiator should work fine. The 13B supposedly cools a higher percentage of the total with the oil cooler. The hot side oil cooler temps are only 220 max. The highest coolant temp was 210 when I climbed WOT from sea level to 3K. The test this morning was with the cowl flap clamped open. The stagation pressure minus the static in the radiator air intake was 6 in of water at 2600 feet and 101 knots indicated. It measured the same at 5K and 115 knots.
       Might fly again this pm with cowl flap closed if I get a nap.
    Test flew and UL( an Odessy that has some major work done on it) today and took a passenger up in it.
    Bernie Kerr, RV9A rotary, N19VX.
     

  • Simple Lycoming Engine Stand
    sent in by Mike Snook [mike at mikesplayground dot net]
       I finally got around to posting pictures of how I adapted an automotive engine stand to hold a Lycoming aircraft engine.
       I’ve seen this topic discussed MANY times on various discussion boards with no apparent solution so I thought the world might be interested in how I solved this problem.
    Here’s a link to the pics
    --Mike

     
  • RV Engine Clinic Report at Mattituck, Long Island,NY
    ...pictures and text sent in by Vern Darley [vern at mindspring.com]

    Twenty mostly RV'ers gathered this weekend at the world-famous Mattituck Engine Overhaul facility on Long Island. Engine guru Mahlon Russell hosted the free TMX 360 sessions.

    A TMX -360 engine was assembled. The group was shown techniques Mattituck has learned in over a sixty years of working on aircraft engines. The group contained a number of professional A&Ps/AI's. All commented on how much they had learned and how worthwhile the day was.

    As the engine was assembled, staff showed us various 'gotchas' that could make even the assembly of a new engine from brand new parts produce numerous life-shortening errors. We were shown various assembly problems that are common place, especially with gear assemblies, pushrods, lifter clearances, and bearing installs.

    Mahlon was a great host and provided breakfast and lunch for the group. Afterwards, a number of us were given a private tour of the Mattituck antique auto museum on site at the airport. Of course, the tour of the Mattituck engine shops was most impressive. It culminated with running a TMX 360 in the fully-instrumented test stand.

    Later a number of us went to a seaside restaurant for what was the best session of the day: learning about aircraft engines as we sat around a fine meal feasting on Mahlon and John's combined 55 years aircraft engine experience.

    Mahlon plans on hosting another free seminar in March. I urge you to attend if you have any questions about engines. Mahlon's phone number is 800 624-6680 ext 305.

    In a few days I hope to have more pix uploaded on www.FalconRV.com

    Vern Darley
    Falcon


     
  • Old Dog Gets New Trick by Mike Toews
    Just finished converting the O-320-A2B to an AIO-320-A2B in my RV4.
    Read article (with pictures)

     
  • Power Chart
    from Wes Ragle" <WRagle at Howellinst.com>
    "Hey Doug,
    ...discussing 75% power. A friend of mine came across the attached (MS Word document) power chart which might answer some of their questions....
    Later,
    Wes (RV-6A)
     
  • Honda's Aircraft Engine
    from Don Hull...
    10/7/03 - These are photos I made on July 31, at Airventure 2003 of Honda's Aircraft Engine currently in development. When I asked the Honda representative about availability and cost, he indicated they were in 'market feasibility' studies. Their testing has included flying a Cessna 337 push-pull twin with one Honda engine and one stock Continental engine. Stay tuned. BTW, the numbers refer to my photo file system.
    See pictures
     
  • 'Lycoming' Yahoo Group (mailing list) 
  • Wood vs Metal Fixed Pitch vs Constant Speed Propellers by Martin Sutter
  • High cylinder head temperatures during take off and climb by John Foy
  • How I Lost 1.5 Qts of Oil in 15 Minutes by Kyle Boatright 
  • Hartzell / Whirlwind Prop Comparison by Randy Levold

  • Alternator Failures
    ...a recent post on the VAF Yahoo Group

    I've had four alternator failures on three different airplanes. In 3 out of the 4 cases, there were ways to see it coming, but those ways were not displayed on the instrument panel.

    None of the airplanes had ammeters -- I've never found those particularly useful -- but all had voltmeters that told me the alternator was no longer producing electricity.

    Case one, over Texas near El Paso...voltmeter suddenly says 12.5 meaning we're on battery voltage, not alternator, which would have been 13.8-14.2. Turned off the non-essential electric stuff and kept going for 1.4 hours. Problem was short in internal windings...not predictable.

    Case two, near home, same scenario. Check all the wires (there's only 3) and found the field wire broken inside ring terminal boot...poor crimp and no strain relief. Coulda found it on actual inspection, but no prior indication in cockpit.

    Case three, same airplane, days of fluctuating between battery voltage and alternator voltage unpredictably. All connections fine, field switch checked fine, belt tension fine, alternator checked on bench. Finally found that the output wire was breaking strand by strand inside terminal connector boot. Replaced orginal six or seven strand wire (bought from Boeing Surplus with no real knowledge...cheap and sort of looked right for the job) with alternator lead from Vans catalog. Solved problem. Cockpit indication could, with some experience, helped pinpoint problem.

    Case four, over the mountains of Idaho, getting late, hour from destination. Blip, no alternator. Action same as case one, but more nervous cause it was getting dark and needed lights. Wire terminal on field wire broke, leaving ring under nut, but letting wire fall off. Another possible inspection find, but no prior indication in cockpit.

    So, 3 out of 4 caused by wiring/connector problems, and those problems caused by ignorance of proper wiring technique or lack of careful looking when cowl was off. Now have alternator connected with properly stripped, crimped and supported wires of the correct type.  So far, so good

    When the wire breaks, you usually aren't going to get a warning. In most flying alternator failure is no big deal...you've usually got more electrons in the battery than you have fuel in the tank. In airplanes with big electric requirements, or vital electric instruments, or electronic ignitions it might be more exciting.


     
  • Carb vs Fuel Injection
    posted in the VAF Yahoo Group by Stein Bruch (http://groups.yahoo.com/group/vansairforce/)

    I've been reading this thread with interest, and noticed that lots of advice has come from people not yet flying...So...here's my 2 cents. And YES, I do have some experience in this area. Here's my setip. I have BOTH carb and FI...

    RV6 - AEIO-360 (Inverted) with Bendix Injection
    RV6 - O-320 with Marvel Carb.

    FI....First, let's get all this "icing" stuff out of the way. Number one, no one in their right mind is going to mount a filter downstream of the servo in an RV, so that debate can quit. The Bendix units are not prone to icing, but the filter is still prone to collecting snow/ice, so an "alternate air source" should still be installed.

    Second, it's a mechanical system that is constant flow, injecting fuel into the intake ports aimed at the intake valve in all 4 cylinders at the same time.

    Benefits to the FI....
    1.You can get a pretty good balance between all 4 cylinders and can lean the crap out of the engines accurately. That being said, it rarely happens without changing/tinkering with the various injectors to get them all balanced.
    2.Little to no worry about icing in the servo itself.
    3.No stuck needle/seat assemblies.
    4.YOU CAN FLY UPSIDE DOWN!

    Benefits of the Carb...
    1.CHEAP-Just overhauled my MA4 for around $200.00
    2.EASY Install. Van's makes a simple bracket for the cables. The FI was a pain.
    3.WAYYYYY easier starting. Since the FI injection tubes rest on top of the engine, when you shut it off hot, they flood themselves. No matter what the installation, or what fishing stories people tell you, I've never seen a FI engine start as well as a carb when hot.
    4.Very little to break. 
    5.Lower Fuel Pressure (2-5lbs vs. 25-30lbs for FI). Oh, and yes you do need a high pressure boost pump ($$$$), bypass, and high pressure engine driven pump for FI.
    6.Lower Overhaul costs. FI=$750-1000.00, Carb=$200-450.00

    In the end, it's pretty hard to justify a FI based on most peoples arguments. It's kind of like the TD/Nose Dragger, TipUP/Slider, 320/360, blah, blah, blah debates. The fact is that a carb will perform just as well, and produce nearly the same fuel flow as FI does. I've flown along side all of the above combinations and Carb vs. FI are usually within .5 gph of each other, assuming you have a good engine monitor which allows you to monitor all 4 cyl's CHT/EGT for leaning. If you can afford it and want it, buy it. 

    My first RV had FI, now my newest has a carb, because I'm cheap, and like the easy starting. That's just my 2 cents so take it for what it's worth. Drop me a note offline and I'd be happy to discuss either system.

    Here's a good hint based on one of our "local" engine gods. He has an RV4 that puts out over 230+HP, Constant Speed Prop, and he works on Lycomings for a living, is a DAR, and guess what...uses a carb.

    Cheers,
    Stein Bruch, A&P
    RV6-N664SB, IO-360 FP
    RV6-N64YU, O-320 FP


  • O-320 H2AD INSTALLATION AND SERVICE by Randal Maurer
       THE ENGINE is a cousin to the 0360E but a 160 hp version. Features are integral accessory section, external mounted oil pump and provisions to run a constant speed propeller. An oil separator is also built into the top rear of the engine. The engine mounts are also removable and can be set up for dynafocal one or two. This engine comes standard with dynafocal one mounts.
       ENGINE SET-UP AND INSTALLATION is straight forward in RV's. Install the fuel pump AC #41270 and a steel oil pressure fitting. Install the engine on Van's dynafocal one H2AD mount. The Vetterman 320 exhaust worked well on my RV-8. NOTE: Some sandcast oil sumps are larger and may interfere on the left forward corner. Vetterman has an exhaust to clear this area.
       BAFFLES: I used the 320 baffle kit. The front and rear baffle will need to be trimmed to fit. The area on the upper cowl above the fuel pump and governor pad on some models will need to be trimmed to allow running clearance.
       FUEL PUMP PLUMBING: The forward mounted fuel pump raises the question whether to plumb the fuel lines under of over the cylinders.  My decision was to install the fuel hoses over the cylinders, being it is the coolest operating side of the engine. I installed Aeroquip Teflon fuel hose rated at 450 degrees. All hoses under the cowl are fire sleeved. Some builders install two electrical pumps instead of a mechanical/electrical combination which would eliminate long fuel hose runs.
       OIL COOLING: I recommend using a nine row or larger Niagra cooler mounted on the rear baffle. Summer tests on my installation included two repeated 4000ft. climbs at 120 IAS. These tests showed oil temperature would not exceed 205 deg.
       SERVICING THE 320H: AD list on my engine is AD80-04-03 oil filter inspections and a 500hr. inspection on the D-3000 mag. The oil additive required for this engine is found in some of the Shell Oil products. (Shell Oil 15W-50 and 100W-plus) I use 100W-plus. It is a single weight mineral AD oil. It is a more cost effective oil and it has the anti-wear additive blended in. Keep dry tappet clearance within limits. Shims can be added or removed to adjust tappet clearance. High time (ie. 500hr.) inspections on lifters can be performed visually by removing the push rods and extracting the lifter with a length of safety wire. DO NOT use a magnetic tool. If any wear is found on a lifter don't despair. Engine publications indicate lifters normally fail before cam lobe damage occurs. 
       For further questions concerning my H2AD installation contact me at 620-782-3030.

    Submitted by: Randal Maurer
    Randal operates a repair station and has been involved in commercial aviation since 1993.

  • Engines and Props (a recent post in the RV-4 Yahoo Group)
    From: "staar" <staar_at_volcano.net> in the RV4 Yahoo Group
    Date: Sat Feb 15, 2003 9:46pm 
    Subject: Engines and Props 
    Hi Guys
       All I can say on the subject is what I had, and It worked for me. Had an IO 320 B1A, that I bought as a core for 4k. Had a friend that is an A /I go through it , cost me $3800.00, total 8800. Bought a used prop, took it to the prop shop, they had a used hub and used my blades, I paid 1k for the used prop, 1k to have it overhauled, and 1k for the used hub. With Van's prices on new C/S props, I would have gone new if it were now. I don't do a lot of Arco, I used it for cross country mostly. I could always burn at least a gallon less per hour than the 4 next to me with 160hp and a wooden prop. Solo climb I would see over 2k per min, but the best part of the prop for me was the braking. I could descend at 3k ft per min and the fixed pitched prop RV's would go through red line if they had their nose down as much as I did. This came in handy when we were over a broken layer and I wanted to get down through a hole. Other things that I liked was not having to use breaks on taxi, when you pulled the power off on final it slows down. 
       Now having said that, I have flown other RV's that have a 160 and a fixed pitch, and for handling and fun, it whips the C/S prop hands down. The simplicity is great, not much to worry about or adjust. The C/S prop makes it much heavier in pitch. (But) One other unexpected plus I got from the C/S prop was to be able to move more weight aft. I took Fred LaForge for a ride one day (he now has his own 4 flying) when he got out he said "well, it handled that good", I said, What Good? He said he is 250lbs, he didn't look it, but I thanked him for stretching my envelope. I don't remember the exact figures but I believe I could put a 200 lb passenger and 40 lbs of baggage and just be at the aft edge of the CG, not that I would do it, but it did work out on paper.
       One other thing I might mention, I changed the elevator skins to .020 It made the airplane much more stable in pitch and trimming was easier.
       A lot of building a custom plane depends on your personal mission, I have a totally different outlook on how I'm building the new one, I have assisted in building 3 others and my views have changed, that is what experience does for you.
    Fly safe, 
    Randy

An Illustrated Guide to Engine Hanging by Jim Norman and friends.

Sam Buchanan's Firewall Forward Section

Anti-vapor Lock Return by Bob Cutting - Bob_Cutting@toyota.ca  
"The pictures here might be helpful to any one trying to install the anti vapor lock return line which is essential when operating on auto gas in high temperatures, hopefully the pictures will be self explanatory."

vaporlock1.jpg (77771 bytes) vaporlock2.jpg (92434 bytes) vaporlock3.jpg (84314 bytes) vaporlock4.jpg (86691 bytes)

Jim Andrew's Engine Setup - O-360 A1A w/Sensenich 85
http://rv8a.tripod.com/engine.html

Firewall Forward Pics (from Jeff Hawkins)
"I posted some pictures in the RV-8 yahoo group list's photo section.  Also included in these photos is a picture of my carbon fiber forward baggage door." (go to the pictures)
Enjoy,
Jeff Hawkins
Atlanta, Georgia
RV-8 Finishing Kit Stuff