Hangar Flying => Hangar Flying => Topic started by: Dave in Eugene on June 04, 2005, 10:04:02 AM
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 04, 2005, 10:04:02 AM
Just wondering... for you folks flying infront of an 0-235 what RPM are you getting static? and what are you using for cruise?
3 hours after rebuild I am getting 2300 static and cruiseing above 2650 for break in... (full rich)
The book (long ez handbook) says should get 2450 minimum static rpm and I am understanding that this means that I am not developing full rated horse power for take off and that it could mean a higher cruiese (158-160 knots at 2600)... Would love you thoughts on the matter...
Dave
Title: Re: 0-235 L2c RPM
Post by: Harry A on June 05, 2005, 10:39:47 AM
Dave you don't mention whether that 2650rpm is full throttle. If both those numbers you mentioned are at full throttle then yes you may be a bit over pitched for your HP. But you mention that you are full rich, I would think you should be leaning as much as CHT allows. you will pick up RPM just from that alone on the top end.
Many Eze pilots have the "Need for Speed" and they will sacrifice takeoff power for a higher top end. You will have to determine what you are comfortable with. If you operate out of short strips or high altitudes you might want that climb performance over speed.
3 hours out of the box on a new OH do you think the engine has settled in that soon? BTW did you see CHT's that went down after 20-40 minutes on that first flight as the rings seated?
Quote from: "Dave in Eugene"
Just wondering... for you folks flying infront of an 0-235 what RPM are you getting static? and what are you using for cruise?
3 hours after rebuild I am getting 2300 static and cruiseing above 2650 for break in... (full rich)
The book (long ez handbook) says should get 2450 minimum static rpm and I am understanding that this means that I am not developing full rated horse power for take off and that it could mean a higher cruiese (158-160 knots at 2600)... Would love you thoughts on the matter...
Dave
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 05, 2005, 10:46:13 AM
harry,
I haven't pushed to full throttle...not sure why not what I am used too. I am sure I can get 2,700+ out it there...
I was watching to see if temps would settle and can't say that I really noticed big changes... #4 CHT is 385 degrees at cruise with the rest being less... I have 415 degrees on climb out but have been keeping it shallow for the break in...
Thanks for your response,
Dave
Title: O-235 rpm
Post by: Ken on June 05, 2005, 10:45:39 PM
I flew my LongEz with an O-235 C2C for 1800 hours; rpm was highly dependent on the prop, air intake system, and exhaust system. Best prop I had (of four) was from Ted Hendrickson (now Rowbear), 62/60, I think, and I routinely saw 2500 at turnup, and cruised at 3000 rpm, both full throttle. A Great American was a little less on both ends. Also rpm is affected by location and type of aircleaner (firewall plans location is a little more restrictive than the ram air type.....some question about increased tendency for carb ice with the ram air type), type of exhaust....2 in 1 plans exhaust a little more restrictive than the four pipe one from Hunt. I've since upgraded to an O-320, and still have both props. Used, but in good shape. Cheap!
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 05, 2005, 11:25:51 PM
Ken,
Thanks for the information..didn't know there were options on the intake or exhaust for that matter...learning curve still steep. Are you in K- Falls?
Dave
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 06, 2005, 07:34:35 AM
...and yes, I'd be interested in hearing more about you props. thanks Dave
Title: 0-235 L2c RPM
Post by: Snappy on June 06, 2005, 12:13:52 PM
Eric Cobb at www.ecob.net makes a good airbox. He is a good information source and flys a Long Ez. Anytime you need a mission, let me know and we can fly down to IZA and see him. He will help you alot.
Regarding your RPM/Prop. Your prop should allow you to run full throttle at your target RPM while still getting acceptable climb. And since your top speed/RPM changes with airframe clean up, everything you do will add to that combination a little.
Gary Hertzler is also very good at airframe efficency and builds a damn good prop. He also flys a very nice Vari Ez.
While you are breaking in, look over the airplane carefully to see if there are any items hanging out in the wind that you can clean up. For me, something as easy as lowering the wheel pants added 2 or 3 kts to the top speed. (this was a Hertzler suggestion)
Steve in KFalls
Title: 0-235 L2c RPM
Post by: Snappy on June 06, 2005, 12:15:32 PM
http://www.ecobb.net/index.htm
sorry for the dead link, this should work.
Steve
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 06, 2005, 02:31:02 PM
I am getting the story... full power is common... even recommended. Not what I am used to. Thanks. Hope we can meet some time and introduce our planes to one another. dave
Title: O-235
Post by: KenK on June 06, 2005, 10:39:23 PM
Dave:
I'm in Bremerton, Washinton. If you're interested in the two used props, I have two in reasonable shape, both from my O-235 C2C powered Long Ez, with a 4'" and an 8" prop extension, spinner and backplate. One of the props is a Rowbear (good prop), and the other is an older Great American, which I used for a backup when the primary prop ate a rock. Happens. If interested, you can email me at tkoskella@wavecable.com. Upgraded to an O-320 E2A, so have lots of parts sitting around gathering dust.
Ken
Title: breakin
Post by: Matt on June 07, 2005, 10:41:48 AM
To get a successful breakin, high power settings may be required. This is so because the higher power settings increase the pressure of the rings against the cylinder walls. Low power settings may cause low ring pressure, which is more likely to glaze and burnish the cylinder wall, which will keep the cylinders from ever breaking in. So, I'd run as high a power setting as your cooling system will allow. Also, fly your breakin hours early in the morning when ambient temps are at the lowest. If you are using new cylinders (from ECI, or Superior), the above seems less critical, but still a good practice...
Matt-
"I am getting the story... full power is common... even recommended. Not what I am used to. Thanks. Hope we can meet some time and introduce our planes to one another. dave"
Title: 0-235 L2c RPM
Post by: rglos on June 07, 2005, 11:28:13 AM
Hi Dave
I also have a complete overhaul on my L2C, Great American 62 x 62 with now 5 hours on it. Recommended break in was at "high" rpm for ten or more hours. I took high rpm to mean full throttle, and rich.
Outside temps lately have been 60 to 70 and oil temp runs around 180 to 210
Static Rpm has been about 2400 and full throttle just a hair above 2800 With this I'm pushing just above 140 kts indicated at 3000 ft
This is at the end of 5 hours.
I didn't take data to start but it seems to be getting better.
I hope these can be used for comparison
Rick
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 10, 2005, 12:18:54 AM
Rick,
Flew today at 5,000 full throttle full rich. Got 2650 Rpm Indicating 145 knots... I will try tomorrow (if time allows at 3,000) and see what I can get.
Amazing that we have the exact same setup.
Dave
Title: 0-235 L2c RPM
Post by: rglos on June 10, 2005, 09:15:57 AM
Hi Dave
Interesting numbers. Even more amazing. Account for variances in drag, tach error differences, airspeed indicators and a small bit to altitude, we are only 5 kts apart with the same plane, same prop, same engine and exactly the same time on the engines.
If you think about it, the spread between your high and low end RPM and mine are about the same. One of us could have a 150 rpm error in the tach.
I would imagine this is pretty typical for us Long Ez's drivers with 0-235 L2Cs
167 mph burning less than 7 gallons and hour on less than 120 Hp-not bad
Opps, almost forgot 860 lbs empty with the big Prestolite starter
Rick[/img]
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 10, 2005, 10:17:48 AM
No kidding.... Amazing...More when I have time.
I am running a digital tach... You? Wheel pants?
880 lbs i think...
.Dave
Title: 0-235 L2c RPM
Post by: Anonymous on June 13, 2005, 12:10:37 PM
The tach is asteam gage type with a sending unit.
Yes I have wheel pants but they are the original football shape type. I'm down for a couple of weeks repairing the radio & will run some flight tests when I'm up & running again. Rick
Title: static rpm
Post by: Jeffco on June 13, 2005, 05:30:05 PM
Dave I have an 235 LC2 with a Catto 3 blade. I see 2500 static and up to 2900 at full throttle at 4000 ft. No wheel pants or gear fairings so I am slow compared to most Longs, I see 135 kts indicated maybe 140 if it's a little colder outside. My brother lives in Eugene and I fly her up there once in a while. Maybe we could get together next time and compare notes.
Jeff Long ez n141 Hawthorne airport serial number 26 still going strong. 500 hours 875 lbs mt
Title: 0-235 L2c RPM
Post by: ozi ez on June 13, 2005, 06:39:10 PM
Hi
For comparison, I have and 0-235 L2c long ez with a 60 x 70 prop, ram air, 830 lbs dry. I see 2420 rpm static and cruise at 161kts at 2700 rpm at 8500 ft. climb is 1600 fpm sustained out of 2000ft when light.
regards
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 13, 2005, 06:47:32 PM
What airspeed are you using for 1600 fpm?
Dave
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 14, 2005, 06:12:09 AM
Rick,
What RPM are you getting at full rich, carb heat, idle...? mine is about 700RPM maybe I'll bring it down just a hair.
Really enjoying the airplane.
Dave
Title: 0-235 L2c RPM
Post by: ozi ez on June 14, 2005, 04:49:24 PM
Hi
1600 fpm climb at 90 kts with 60 litres of fuel aboard the pilot and no baggage, with an air temp of about 18C and the QNH of about 1020mb
Hard idle is about 760 rpm when warm and a little faster when cold.
Ram air helped by about 50 rpm static and the prop added about 15 kts over the BT 62 x 66 climb prop.
Title: 0-235 L2c RPM
Post by: Anonymous on June 16, 2005, 05:06:44 PM
Hey Dave
At Idle I'm seeing about 850 rpm, full rich, no carb heat. This is too much as it keeps pushing me down the runway. I had it set to 650 on the old engine but I will leave it for now untill I get few hours on the engine.
I don't think it will hold 650 right now & I'm not going to chance it just yet.
Boy the numbers were a little surprising on the Cato prop and 160 Kts @ 8,500 ft. My rewiring of the radio is done now so I will try to get some more numbers for you.
Rick
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 16, 2005, 06:49:01 PM
Wow...nice prop... Isn't there a waiting list for those? congrats on your radio...nice to have stuff working,
My next task is rain proofing my plane. i have a big gap in the front of the canopy and want to keep water out of my panel.
Dave
Title: 0-235 L2c RPM
Post by: rglos on June 19, 2005, 04:42:13 PM
Dave
Opps, sorry !
I did not mean to imply that I had the catto Prop. Nice thought though.
Radio works, intercom works, all new wiring etc.
I'm off next week and will redo some of these numbers.
Can't see how you get 161 Kts out of a O-235 But If our friend in Europe says so then OK
Rick
Title: 0-235 L2c RPM
Post by: ozi ez on June 20, 2005, 12:51:22 AM
Dear gentlemen,
I know that 161 kts out of an 0-235 sounds a bit unlikely, but it turns out to be true. Let me tell you how it happened.
Originally I had a B&T 62 x 66 prop that gave about 143 kts at 2700 rpm but i noticed that by allowing the engine to rev out through 2850 rpms and higher only about 5 extra knots was available. This is not what you would necessarily expect as the 100 rpm from 2600 to 2700rpm gave just over a 10 kt increase in speed. Something fishy going on here!
Taking the prop off and measuring the pitch at 4 inch intervals radially showed a pitch that varied somewhat erratically from 75 inches at the root through 65 inches at 2/3 rds radius to about 55 inches at the tip. A bit of calculation showed that at 2700 rpm and 143 kts, the tips were flying at -12degrees incidence. This tends to explain why my long Ez wouldnt go any faster, as at higher rpms the tips were starting to oppose the rest of the prop.
At this point a good friend stepped in with a loan of a "Henry"prop from his own soon to be finished Long EZ. Measuring this prop showed a consistent 68-71" pich at all stations, so a copy was made for experimental purposes. Initially at full diameter of 63" my engine bogged down at about 2200 rpm static and wouldnt get much past 2600 rpm at any altitude. Not good, but the airspeed was 153 kts! Worth persevering with.....
Then followed a number of sessions of reducing the diameter by 1" at a time, fining the tip profile and rebalancing, until the static rpms came up to 2370 and the airspeed was at 157 kts at 2650 rpms. At this, it was till a little difficult to get to 2700 rpms at 8500 ft.
The next fix was a home brew ram air system that increased static rpms to 2420. Now I can get to 2800rpm at altitude anytime! Some selective polishing and aerodynamic tweaks have yielded the extra knot or so to give me 161 kts at 8500 feet at 2700 rpms, though from habit, i do cruise at 2650 rpms and 158 kts at 8500 feet, generally.
best regards
Carolyn
Title: 0-235 L2c RPM
Post by: Dan Patch on June 20, 2005, 11:53:06 AM
Carolyn,
Nice report! This is the kind of useful information on what you measured, conclusions drawn, modifications made, and the results of those modifications that really helps others determine what might be checked on their planes, and the degree of potential improvement. :D
Title: 0-235 L2c RPM
Post by: rglos on June 20, 2005, 12:23:51 PM
Carolyn,
Great report and very useful.
I'd bet a bunch of your fellow EZ drivers are really thinking hard including me.
Thanks again
Rick
Title: cruise rpm and props
Post by: strider on June 23, 2005, 08:12:41 PM
Man, our little VariEze must be so draggy! We recently had a very good mechanic go over our O-235 L2C during our Condition Inspection, and it is now running better than ever. Our climb prop is a Culver 60 x 65, and it was turning 2,800 rpm at 8,000 ft, with speed of 130 kts. Static rpm was 2,500.
So I put our Culver 60 X 67 cruise prop on the plane. Static rpm is 2,400, and top end is not 2,700 at 140 kts. No wheel pants quite yet, recently installed the TE Fences and Vorts. Nose wheel-well is made for a nosewheel door that we do not use. And I think the engine has too much right-thrust. You can easily see the engine angle with the plane parked, and it always turns right (yawing) while cruising.
Seems like it's the slowest EZ flying ...
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 25, 2005, 10:03:29 AM
Ever gotten scared on take-off?
The other day I took off with a 165lb friend in the back and 25 gallons of fuel. I way about 175. I think we ate 2,800 feet of runway on a 3,500 runway. altitulde 535 ASL and temps in the 70's.
Makes me real thoughtful about High hot heavy and humid.. Also makes me thoughtful of an 0-320!
i would appreciate experiences and thoughts.
Thanks,
Dave
Title: 0-235 L2c RPM
Post by: aaronh on June 25, 2005, 02:12:54 PM
I've had one take off that gave me a pretty good scare... off meadowlake field. It was not the warmest of days.. around 55 deg. I had about 1/4 tanks and a pretty light pax at ~130lbs. Meadowlake is at 6800' with 6000' of runway. PLENTY for a moderately loaded longez w/235!
I had a stiff cross wind. Nearly at 20knotts. It was also not consistent. I have found the ez to handle pretty well in x-winds overall so.. full throttle I was rolling. Not very straight though. full left pedal... hmm not enough even over 30mph... hair of brake.. ok I'm straight again. I found myself having to ride the left brake quite a bit. Every time I tried to get off of it I'd have to get back on harder to pull the plane back straight. A bit over mid field I thought about aborting but I had 70mph... another 5-8 and I'm flying. That last 8mph took FOREVER! I burned up 3/4 or more of a 6k' field that day. If I had to abort I'm not sure I wouldn't have been in weeds at the end. Now think if it was hot with more fuel and a heavy pax.... ugly ... real ugly.
I absolutely love my EZ, but a short field performer it is not! It is horribly underpowered at high density alts. And add to a high alt takeoff having to use a brake in strong x-winds..... the long in longEZ is for loooooooong takeoffs.
I'm a bit more conservative after that takeoff. If the x-wind has me too hard on a brake to stay straight, I'll make mid-field my abort point. iI I'm not lifting off by then, time to pull that throttle and use both brakes.
Title: 0-235 L2c RPM
Post by: rglos on June 27, 2005, 08:04:06 AM
The weight, altitude and passenger is not unusual. Should have gotten off better.
Tire pressure, winds down the runway and lift off speed are among many factors. Try this when your by yourself. Pull the nose off gently at 55 kts (it reduces ground friction a little less than a third)
I tried this and it works but I have to admit that normally I pull back at about 60 to 70 kts.
Rick
Title: 0-235 L2c RPM
Post by: Dave in Eugene on June 27, 2005, 09:07:51 AM
interestering. I realize that there was a good cross when I had my "raised awareness" take-off. So I was on my left brake some on initiation.... I am sure that that added to the condition.
Has anyone noticed major differences after an 0-320 conversion?
Dave
Title: 0-235 L2c RPM
Post by: rglos on July 01, 2005, 12:00:17 PM
OK guys
I just got a confirmation from my earlier posts to Dave.
Last night it was 91 degrees, west wind at 15. I took of at 7:30 pm.
I took it up to 3000 msl, trimed out and ran the throttle full foward.
I was pushing 143 kts indicated at 2750 rpm. I took off the CHT probes a few years back so I can't tell what the CHT was. Oil pressure was pegged at over 90 psi and oil temp waas running about 210 degrees. When I stopped pushing it, and dropped down to 120 Kts the Oil temp dropped down to 200.
The engine still has less than 10 hours on it.
This has been a long running post but I would be interested in comparison data or break in tips.
Title: 0-235 L2c RPM
Post by: Anonymous on July 01, 2005, 12:49:26 PM
90 psi oil pressure sounds way to high to me. Have you made any adjustments to it? I would expect 50 - 60????
RPM at max throttle sounds a little low, but this is more a personnel preference. I used to run at 2900rpm.
The oil temp sounds like it may be dialed in, just a tiny high but acceptable.
Waiter
Title: 0-235 L2c RPM
Post by: rglos on July 01, 2005, 05:20:30 PM
Thanks Waiter
Meanwhile I found my Lycoming Operators Manual I bought 20 years ago.
Oil Pressure on all Models Except L2C & N2C
Max Min Idle 90 60 25
Models L2C & N2C
Max Min Idle 90 60 15
Start & Warm-up 100 Start & Warm-up N2C 115
Oil temp
Above 60F Desired Max 180F 245F 0 to 60F 170F 245F
Below 0F 160F 245F
Rick
Title: 0-235 L2c RPM
Post by: rglos on August 01, 2005, 08:12:50 AM