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Ground roll and climb out RPM?

Turbo69bird

Well Known Member
What should my RPM be with a 0320 160, metal sensenich prop, need to look up size and pitch still

I'm only seeing 2260 on ground roll and climb out, placard on panel,says not to exceed 2600 but I'm reading numbers more like 2750 in other threads.

Just wondering where it should be. I've got to climb out of my 2100 ft runway pretty flat to achieve 90mph and getting cyl head temps at 400 to 410 before 1000 ft which I'd like to be cooler.

Top end is pretty good in my opinion at about 178 mph at low (3500) ft altitude (don't recall rpm ) though I really haven't pushed it much. To see if it'll run faster.


I just feel like the climb out is kind of anemic compared to the 180 hp archer I flew and my friends 7a with 195 hp constant speed prop climbs out like an animal.

Thoughts?
 
2600 is the limit!

We've got a 6A with O-320 and Sensenich. On the takeoff roll, I want to see close to 2300 RPM. 2260 wouldn't scare me. Solo, I climb at close to 1000fpm. Once I feel OK about safe altitude, I like to cruise climb at 130kt indicated and the rpm will rise to almost 2500. Better cooling and visibility, too. With the extra HP that I can make with more rpm it still climbs about 7-800fpm. I can usually get 155-160 kts true in level flight at 3.5K. At that altitude, I can pretty much leave the throttle full open but dropping the nose at all will overspeed the prop.

400* CHT at pattern altitude is too high. You should do something about that. Baffle sealing, correct timing, enough fuel flow.

Careful with the prop rpm. The 70CM series on the O-320 is limited to 2600. There is apparently a nasty harmonic at about 2650 that would fail the prop if you operated there very long. Calibrate your tach and stay under the limit.

Have fun,

Ed Holyoke
 
Rpm

First step is to make sure the tach is accurate.


Don Broussard
RV9 Rebuild in Progress
57 Pacer
 
Tach is an EI unit and just had it serviced to be sure it was accurate.

So the 2260 is not really way off then I expected higher rpm on take off. Sounds like top speed it's pretty similar too. This thing will climb fine after I reach 100 it's getting up over those first set of trees that's a little daunting and as it gets hotter I'm more concerned. This was with myself at 230 and pass at 150 at about 70 degrees. I've done the washer trick and baffling seems to be sealed pretty well. Don't know what else to do for CHTs to get them down. Once I level off it's fine but there's no way I could climb at 80mph in this I'd over heat it.
If I flatten it out to get 100 mph climb I just touch 400 cht by pattern altitude. But I can't always climb out at 100 and clear obstacles.

I'm thinking of wrapping the plane and that would add another 23 lbs can't even imagine climb performance at that point. 😳

I wil say I probably keep 40 lbs baggage at all point she in time with tools etc but I'd think I'd be fine with that. This was also at 75% fuel.
 
Climb at whatever speed is necessary to clear the trees at the end of the field, but after that, accelerate to 110-120 knots. Your climb rate won't change much, but your CHT's will benefit substantially.
 
Don't worry about 400?F CHT's on climb out. Lycoming lists 500?F as max CHT. They do suggest you stay below 400?F for continuous operation.

It is not uncommon to see 425 in a Cessna or Piper on climb out.

Once you level out, your CHT's will come down.
 
Do you have the landing gear fairings installed? My -7A does not yet have them and, according to the installation instructions, could cost 20-25 HP in drag.

I have similar numbers for my 180 HP fixed pitch 3 blade Catto but with full tanks and two passengers can still get 800 FPM climb at 105 knots. CHT is fine until I start to try leaning out above 3000 ft.

Watch your EGT on take-off and try to maintain that temp while climbing via mixture control. If your CHT is still high in that realm, you have cooling/baffling issues to solve.
 
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To answer your question, if I remember correctly my initial full throttle roll is about 2160. It very quickly starts to increase with ground/air speed.
I have a ECI I0-320 with a fix pitched Catto three blade. I can hit redline at low altitude and full throttle at about 50 rich of peak. I believe I am pitched about perfect.
 
My -6 with 0-320 b2b, 160 hp, catto 3 blade gen 3 prop weighs 1044 lbs. i take off from a grass strip with half flaps with 2200rpm static and climb to 200 ft to clear the trees at 80mph and lower the nose. I can't see over the nose at this speed. When i have a positive airspeed trend, i retract the flaps and set a 500fpm climb until the the tach reads 2450rpms. I then climb at whatever this speed is. This gives me 1000-1200 fpm depending on weight and temperature with no tendency to overheat. At 8000ft DA, i turn 2650rpms for a four way gps avg tas of 182.5mph. I think i am about 2" overpitched, but when i add the dual pmags, i think i will turn 2750rpms or so. It sounds like with your prop, it is doing fine except for the overheating. Check your baffles and carb jet size for proper fuel flow on takeoff. You could be running excessively lean even with the mixture knob full forward.
 
Climb at whatever speed is necessary to clear the trees at the end of the field, but after that, accelerate to 110-120 knots. Your climb rate won't change much, but your CHT's will benefit substantially.

110 to 120 is a pretty shallow climb out and with noise abatement procedures in effect I don't know that that sallow of a climb out would be appreciated in my area to pattern altitude.

at a 90 mph climb I'm at the end of x wind by the time I reach pattern altitude.
 
I should also include that it's typically only no 1 that is that hot the rest are usually 20 degrees cooler.

My concern was the rpm being so low as others have told me that was incorrect and pitch change was in Order.

My typical rollout is nose wheel high asap, 15 * flaps, lift off pitch for 80 as soon as I clear obstacles ( usually not by much maybe 40 ft on a 2100 ft runway with 20 ft trees immediately and 50 ft a little farther out) I'll pitch for 100 if possible climb to 1000 pull power back some and use enrgy to reach TPA of 1200. Then level out to 120 and start cooling things down.

Occasionally at full throttle in cruise I'll see higher CHT temps than I'd like but typically stays pretty cool in cruise.

This past night I had all wheel pants off for repair work so that could have been a contributor because it was worse than normal.
Over all though doesn't sound like I'm that far off from others which makes me feel a little better.

No one sells a hotter cam for these babies to wake them up huh? Could use a little more HP 😀 How about ported heads ? Actually I've been told push rod length could make some difference?

I feel like my baffling is pretty good and none of the RV guys local seem to think it's got issues w baffling
I did just shimm the mounts for better alingmeng with the cowl which I felt would help my cooling as well because the baffling is getting closer to the cowl for better sealing?


Thank you to all who have replied btw.. I very much appreciate the help.
 
If it just one cylinder gets hot, check the cht probe itself. I had one reading 50degs hot several years ago on a two stroke engine. Pull the probe out and put in a coffee can of water. Heat the can with a propane torch till boiling. You gauge should read 212degs +- 5 degs if everything is working correctly. The temp your gauge reads can be effected by the many things.

10-1 compression pistons, dual pmags and a little polishing of the ports will get you 180hp out of the 0-320. That is my plan after the panel upgrade.
 
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110 to 120 is a pretty shallow climb out and with noise abatement procedures in effect I don't know that that sallow of a climb out would be appreciated in my area to pattern altitude.

at a 90 mph climb I'm at the end of x wind by the time I reach pattern altitude.

With a FP prop, you'll get about the same climb rate at 110 knots as 90 mph. At 110 knots I see roughly 1,000 fpm.
 
I feel like my baffling is pretty good and none of the RV guys local seem to think it's got issues w baffling

3 out of 4 RV's I have ever looked at / inspected had something that could be improved on the baffles. The majority of the time when it was on an airplane with cooling problems there was a serious issue.

My point being that this mean 3 out of 4 RV owners that you get advice from will say that it is fine...... but it might not be.

Don't take anyone word for it. Do a light test.
With the hangar dark, shine a light from the upper side of the baffling to the lower side.
A good baffle installation will be one that light passes only in areas that it is passing cooling fins.
Then evaluate the baffle seals. Particularly at the front.

A total leakage area of just a couple of square inches can have a significant impact.
 
3 out of 4 RV's I have ever looked at / inspected had something that could be improved on the baffles. The majority of the time when it was on an airplane with cooling problems there was a serious issue.

My point being that this mean 3 out of 4 RV owners that you get advice from will say that it is fine...... but it might not be.

Don't take anyone word for it. Do a light test.
With the hangar dark, shine a light from the upper side of the baffling to the lower side.
A good baffle installation will be one that light passes only in areas that it is passing cooling fins.
Then evaluate the baffle seals. Particularly at the front.

A total leakage area of just a couple of square inches can have a significant impact.

I'll try the light test and see what I get, I don't have a hangar so I'll have to wait til I can borrow one for a little while.
 
With a FP prop, you'll get about the same climb rate at 110 knots as 90 mph. At 110 knots I see roughly 1,000 fpm.

As it is I rotate get about 10 ft up and level out as long as I can to get the speed up before climbing out. I'm Not going to reach 100mph most times before the end of the runway / trees, never mind 110 knots and to stay in the pattern (and climb like I do in the 180 archer)I'd only degrade the speed not pick up speed.or I'd be on downwind by the time I reached that speed and pattern altitude ) If I was climbing straight out maybe, but as I said it'd be a very shallow climb out til I reached those speeds.
 
As it is I rotate get about 10 ft up and level out as long as I can to get the speed up before climbing out. I'm Not going to reach 100mph most times before the end of the runway / trees, never mind 110 knots and to stay in the pattern (and climb like I do in the 180 archer)I'd only degrade the speed not pick up speed.or I'd be on downwind by the time I reached that speed and pattern altitude ) If I was climbing straight out maybe, but as I said it'd be a very shallow climb out til I reached those speeds.

The idea is to climb at VX until you clear the obstacles, then VY or higher (say 110 knots) afterwards for cooling.
 
RV6A performance

Hi Turbo69bird, RV's with lower HP engines are sensitive to weight. Sounds like you are over Van's recommended Gross weight as loaded. I do notice the difference with another person and full tanks over just me (180 pounds)and low tanks. Numbers for my plane are 1050 Emtpy weight. Stock O-320 engine with Sensenich 79 inch pitch Propeller. Full throttle static RPM is about 2250. Top speed is 190mph at 2600rpm down low (1500Feet). Prop can be oversped at almost any altitude. This rpm (2250) will not increase after takeoff until you lower the nose but the plane should continue to accelerate. Look up Vans numbers for Climb and speed numbers, you should be close.
Daverv6A
 
As it is I rotate get about 10 ft up and level out as long as I can to get the speed up before climbing out.

Intuitively this sounds like a good idea but it isn't good technique with your plane and won't produce max climb performance.

Initial climb immediately after liftoff should be 85-90 kts, then when well clear of obstacles allow the plane to accelerate to ~115 kts while continuing the climb. This will result in good climb performance and keep the engine cool.

My plane is a RV-6, O-320, Sens 80". Loading the plane with passenger and fuel results is a very different flight from solo but the same climb technique should be used.
 
A Few Comments on Technique and Equipment

Ten to fifteen degrees of flaps will help you get "unstuck" faster and so will raising the nose as soon as you're able. However, raising it more than a couple of inches above the grass will detract from your performance. Also, 10 feet is far too high to take advantage of ground effect. I don't have a "6", but the speeds you're using don't sound appropriate for Vx and Vy. Too slow also detracts from performance. Your aircraft with an O320 and FP prop should out-perform a Cherokee 180.
Finally, you might also check your tire pressure (45-50 psi) and the ground clearance of your gear fairings.
Terry, CFI
RV9A N323TP
 
0 360 Fp Prop

I had an RV 6 a with 0-320 Lyc and a Sensenich coarse pitch ,wood prop.
My climbs sound very similar, but # 1 & 2, very easily went above 400 deg F after lift off and climb at 90kts. My fuel flow was ok and baffles were ok, so as others have suggested ,I lowered the nose to 120 kts and found temps improved with altitude.
I had the plane for 8 years and it was ok. As I needed better climb on my short strip, I built RV7a 180 hp and constant speed prop. This is safer for me, especially when hot weather and full load.
 
Appreciate the info guess it's doing what it should for the current set up. A little recent reading made me think k a catto prop might help somewhat.
 
Ten to fifteen degrees of flaps will help you get "unstuck" faster and so will raising the nose as soon as you're able. However, raising it more than a couple of inches above the grass will detract from your performance. Also, 10 feet is far too high to take advantage of ground effect. I don't have a "6", but the speeds you're using don't sound appropriate for Vx and Vy. Too slow also detracts from performance. Your aircraft with an O320 and FP prop should out-perform a Cherokee 180.
Finally, you might also check your tire pressure (45-50 psi) and the ground clearance of your gear fairings.
Terry, CFI
RV9A N323TP


The archer 180 I fly will out climb (initially) this RV6 like a helicopter compared to butterfly. Lol

Once it's (RV) at 100 mph or better that's a different story, but the archer I can pitch up and hold at vy all day long without it getting hot and it klimbs out nicely. Love my 6 and it does a lot of things wonderfully, but climbing out isn't one of them. I do take off with the flap setting recommended by many on vaf set with my Angle finder and marked.

Plain and simple this 6 needs to be moving fast to climb out well.
 
The archer 180 I fly will out climb (initially) this RV6 like a helicopter compared to butterfly. Lol

Once it's (RV) at 100 mph or better that's a different story, but the archer I can pitch up and hold at vy all day long without it getting hot and it klimbs out nicely. Love my 6 and it does a lot of things wonderfully, but climbing out isn't one of them. I do take off with the flap setting recommended by many on vaf set with my Angle finder and marked.

Plain and simple this 6 needs to be moving fast to climb out well.

Climbing well can mean a lot of different things.....

Flying my 180 fixed pitch RV-6A solo I see initial climb rates (down near sea level) of 1800+ FPM. I would call that climbing well.

A 180 HP RV-6(A) with a properly matched propeller, at its worst, will out climb a Piper Archer on its best day.
Sure, it does it at a higher airspeed but it also accelerates to that speed in the same amount of time it takes the Cherokee to get to Vy so it doesn't matter (BTW, most people climb at 120 or so... it only gives up a small amount of climb rate but does help cooling).
 
HP

Aircraft Speciality has a stage 3 cam grind that will wake that engine up. Couple that with a good port and polish job on the heads and finish it off with 9.5/1 pistons and you should be good to go. However, you may have to ditch that metal prop after making all these changes and go with a Catto. I'm not a fan of 10:1 and higher compression if engine longevity is a consideration.
Good luck with your RV!


I

No one sells a hotter cam for these babies to wake them up huh? Could use a little more HP 😀 How about ported heads ? Actually I've been told push rod length could make some difference?

I feel like my baffling is pretty good and none of the RV guys local seem to think it's got issues w baffling
I did just shimm the mounts for better alingmeng with the cowl which I felt would help my cooling as well because the baffling is getting closer to the cowl for better sealing?


Thank you to all who have replied btw.. I very much appreciate the help.
 
Y'know, everything is a compromise with a fixed pitch prop. I have a 6A with 160hp engine and 80" sensenich, I get around 2250 rpm on the runway and can overspeed the prop (over 2600rpm) at low level flat out, I don't know by how much, I am not brave enough to find out. Climb rate at max weight is around 1100fpm, but at 110kt+. I also have a low pitch wooden prop, it will turn 2350 on the runway and climb really strongly. It is also 10kt slower (at 2700rpm) than the Sensenich at 2600. But the engine will rev to 2900rpm and the airplane will be doing 10kt faster than the Sensenich at 2600.

I have tried several wooden props, so far the Sensenich is the best compromise for the flying I do, most of the time. Better clmib performance is always available if you are willing to trade cruise speed. The folks who have posted have reflected my experience - take-off and climb in these airplanes changes a lot with weight, and climb rate is constant over a wide speed range, but CHTs reduce with a higher climb speed. I tend to accelerate balancing on the main wheels, lift off at around 60kt, start agentle climb immediately aiming for an initial climb speed as low as 80kt (90mph) to clear trees, then accelerate to normal climb speed. The only silver bullet is a constant speed prop. By all means try a Catto prop, but don't expect a significant change in performance at both ends of the envelope.
Pete
 
Ok so an update, my prop is a 70cm 79 pitch Don’t know if anyone reworked it.

I see between 2150and 2200 on the runway. And today I pitched it for 100 mph it climbed out at 700ft per minute. This was a light rainy day at about 60 degrees. Two occupants approx 200 lbs each and 15 gallons fuel per tank.

I should add that compressions are all good on the engine 78/80 or better, and the engine only has approx. 250 on it smoh.
Timing has been checked as well. Thoughts on those performance numbers appreciated. (I �� think) ��
 
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Ok so an update, my prop is a 70cm 79 pitch Don’t know if anyone reworked it.

I see between 2150and 2200 on the runway. And today I pitched it for 100 mph it climbed out at 700ft per minute. This was a light rainy day at about 60 degrees. Two occupants approx 200 lbs each and 15 gallons fuel per tank.

I should add that compressions are all good on the engine 78/80 or better, and the engine only has approx. 250 on it smoh.
Timing has been checked as well. Thoughts on those performance numbers appreciated. (I �� think) ��

You took off at a few pounds over gross for the RV-6 (~1680 lbs). I would consider 700 ft/min at that weight with an O-320 turning a cruise prop to be excellent preformance. You have a good airplane.
 
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You took off at a few pounds over gross for the RV-6 (~1680 lbs). I would consider 700 ft/min at that weight with an O-320 turning a cruise prop to be excellent preformance. You have a good airplane.
200+200+(15+15)*6 = 580? My -6 is only 999lb, that would put me at 1579. I didn't see his empty weight specified?
 
200+200+(15+15)*6 = 580? My -6 is only 999lb, that would put me at 1579. I didn't see his empty weight specified?

I didn't see empty weight either so made a fudge factor guess of 1100 for the RV-6A. Our planes get heavier with age (and all the stuff we haul arround...). :)
 
You took off at a few pounds over gross for the RV-6 (~1680 lbs). I would consider 700 ft/min at that weight with an O-320 turning a cruise prop to be excellent preformance. You have a good airplane.


My weight and balance lbs

Man that?s about useless at 1680most of my buddy?s are 230 240 lbs.

My plane as I recall was 1150 empty weight but I?ll check on that. It?s got full interior and insulation behind it so I assume its heavy. I?m planning to re-scale it since I just did vinyl wrap over my paint. I did wet sand it a bit to shave some weight off the paint, but wanted the corrosion protection.

Problem is at the weight of most people I know, if I pull fuel out it gets and aft CG.so I do a dance beteween gross and aft cg. I also carry a hand held radio, two I pads a back up battery pack, my cell phone, my cover, chocks etc But I do have the carpet out 🤔

However (I feel) it still, doesn?t climb great within me alone in it. I lol get some numbers with me alone and half fuel. For comparison. It is a nice airplane just doesn?t climb like others. I?ve had people comment on it after most takeoff and landings.

I have two friends with RV7s and they climb like helicopters. As does the archer I fly.
 
My weight and balance lbs

Man that’s about useless at 1680most of my buddy’s are 230 240 lbs.

My plane as I recall was 1150 empty weight but I’ll check on that. It’s got full interior and insulation behind it so I assume its heavy. I’m planning to re-scale it since I just did vinyl wrap over my paint. I did wet sand it a bit to shave some weight off the paint, but wanted the corrosion protection.

Problem is at the weight of most people I know, if I pull fuel out it gets and aft CG.so I do a dance beteween gross and aft cg. I also carry a hand held radio, two I pads a back up battery pack, my cell phone, my cover, chocks etc But I do have the carpet out ��

However (I feel) it still, doesn’t climb great within me alone in it. I lol get some numbers with me alone and half fuel. For comparison. It is a nice airplane just doesn’t climb like others. I’ve had people comment on it after most takeoff and landings.

I have two friends with RV7s and they climb like helicopters. As does the archer I fly.

You have a very heavy RV-6A (my RV-6 hit the scales at 1010 lbs...painted). Guess your choice is to be satisfied with the performance you have or get a different airplane.....me thinks the O-320 and cruise prop are doing about all they can.
 
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I did a max weight takeoff with my 160hp 0-320 rv 6 and catto 3 blade 67x70? prop a while back. The takeoff weight was 1730 lbs. This was 1064 empty weight, 245lbs pilot, 240lbs pax and 30 gallons of fuel. The density altitude was 1500ft as reported by asos and temp was 31deg C with relative humidity of 85%. We used 1 notch of flaps to approx 300 ft and WOT showed 2200 rpms. This gave us an inital climb rate of 600-700 fpm at 80-90 mph to clear the trees on a 4000 ft concrete runway. After reaching 300 ft at about mid field, flaps were retracted and established a 110mph cruise climb at 2450 rpms with 700-800 fpm climb rate. It flew very much like a cessna 172 departure profile at high weights and temps. This weight and balance solution gave us 8 gallons to burn without the aft cg limit being exceeded. We climbed to 2000ft and did a series of stick pull phugoid manuevers to check the pitch stability. The airplane respond with slow, but positive stability all the way to the aft cg limit. It did become slightly more pitch sensitive, but nothing scarey. I would not exceed the aft cg limit under any circumstances after this test. I used 5 mph higher speeds in the pattern, 95mph downwind and 85mph on final. It three point landed very nicely. The landing weight was 1675lbs with a landing cg of 76.79". Now that the new panel is installed, it is time to start planning a whirlwind c/s prop upgrade. It never ends. 😜
 
I appreciate all the answers, I?m still going to do some more testing and most importantly scale my plane to see exactly where it starts out in the weight end of things.

Thought about repitching the sensenich but if I find out it?s somethung else sticking exhaust valve , cam lobe etc then I?ll be stuck with a prop that?s not optimal. And it might just simply be that the ole girl has gotten porky over the years, lord knows the pilot and passengers have .lol.

The more o hear others numbers the more it seems fairly normal. We?ll see and I?ll update the thread.
 
By the numbers...

Jeff,

I recommend you do as you planned: a good W&B, compression check on the engine.
Additionally:
1.Try leaning slightly on takeoff roll if you haven't already.
2.If you're running mags, REM-37BY plugs are a bit hotter and I gained 50 static RPM with them on my 0-320 powered RV4. (E.I will gain you almost 100RPM)
3.Get rid of any excess weight you can (heavy battery, interior,insulation, starter, alt, unneeded junk onboard you mentioned, it all adds up) Mount the lighter battery on the firewall to help CG.
4.Consider selling rather than re-pitching your Sensy metal and purchasing a Catto or similar composite or wood climb prop. They reduce your EW, far better climb rate and smooth. (Of all Nine props I've tested over 25 years, The Sensy metal is my least favorite, 2600RPM restriction, no acro etc.)
5.Consider Electronic ignition if you haven't already as it adds performance.
6.Fly at reduced fuel loads, that helps too especially if your passenger exceeds 200lbs. *I used to have a rule in my RV4 to carry no passenger above 200lbs for CG reasons. (consider girl passengers instead...:))


The lighter they are, the better they fly....
V/R
Smokey

PS:My RVX is basically an RV6 fuselage mated to RV4 wings and tail. It weighs 945lbs empty with an 0-360J2A, (180HP de-rated Robinson R22 engine) dual E.I., 2 blade Catto lightweight starter/alt/batt 170lb Pilot.
(All my local flying is done at less than 1/2 fuel as I perform Acro and the airplane simply flies better.)
By the numbers:
Solo climb rate with half fuel 100KIAS is 1500FPM on a 95F TX summer day.Full fuel with a 120lb pax/25lbs baggage is 1000FPM (add 500FPM to both for winter temp climb numbers

PSS: We visit Telluride CO (9070' elev) every summer and I use my summer takeoff numbers there as a worst case performance scenario.
2 on board, 1/2 fuel and 25lbs of bags (I never take off full fuel/pax/bags in the mountains) 75F static RPM is 2050, takeoff 2100 leaned out and climb at 100KTS is 2250@500FPM.
 
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Jeff,

I recommend you do as you planned: a good W&B, compression check on the engine.
Additionally:
1.Try leaning slightly on takeoff roll if you haven't already.
2.If you're running mags, REM-37BY plugs are a bit hotter and I gained 50 static RPM with them on my 0-320 powered RV4. (E.I will gain you almost 100RPM)
3.Get rid of any excess weight you can (heavy battery, interior,insulation, starter, alt, unneeded junk onboard you mentioned, it all adds up) Mount the lighter battery on the firewall to help CG.
4.Consider selling rather than re-pitching your Sensy metal and purchasing a Catto or similar composite or wood climb prop. They reduce your EW, far better climb rate and smooth. (Of all Nine props I've tested over 25 years, The Sensy metal is my least favorite, 2600RPM restriction, no acro etc.)
5.Consider Electronic ignition if you haven't already as it adds performance.
6.Fly at reduced fuel loads, that helps too especially if your passenger exceeds 200lbs. *I used to have a rule in my RV4 to carry no passenger above 200lbs for CG reasons. (consider girl passengers instead...:))


The lighter they are, the better they fly....
V/R
Smokey

PS:My RVX is basically an RV6 fuselage mated to RV4 wings and tail. It weighs 945lbs empty with an 0-360J2A, (180HP de-rated Robinson R22 engine) dual E.I., 2 blade Catto lightweight starter/alt/batt 170lb Pilot.
(All my local flying is done at less than 1/2 fuel as I perform Acro and the airplane simply flies better.)
By the numbers:
Solo climb rate with half fuel 100KIAS is 1500FPM on a 95F TX summer day.Full fuel with a 120lb pax/25lbs baggage is 1000FPM (add 500FPM to both for winter temp climb numbers

PSS: We visit Telluride CO (9070' elev) every summer and I use my summer takeoff numbers there as a worst case performance scenario.
2 on board, 1/2 fuel and 25lbs of bags (I never take off full fuel/pax/bags in the mountains) 75F static RPM is 2050, takeoff 2100 leaned out and climb at 100KTS is 2250@500FPM.



Thanks so much for the detailed info. That goes for everyone who replied. I?m hoping to scale in next week. One reason I don?t fly with reduced fuel loads is the CG and that?s also the reason I haven?t switched to a light prop.

Here?s the airplane for those of you who?d like to see it.
Www.vansrv6.com

My battery is fairly light and mounted on the floor up against the firewall. Sealed gel type.
I do t think I even know anyone under 200 lbs except girls. Lol. The wife frowns upon too many of those pax though. Lmao
I don?t know that it really climbs out much better with me alone in it. Honestly, I know it floats more on landing but in take off I don?t really notice that much. Difference.
 
One unfortunate aspect of this situation is that you have not experienced the real RV performance envelope. Because you are always flying heavy, your plane never performs as Van intended. Excess weight affects all corners of the envelope, not just climb.

A flight in a light RV would be an eye opener. :)
 
Didn?t look at much today just took my kid up for a flight but did notice that with her light weight in it pitched for 100 mph rage of climb was 1000 ft per minute. Didn?t feel like it got off the ground much quicker though. Maybe slightly but not significant.

Didn?t check my static rpm I will next time out though. Had a very short window and the focus was on taking the kid for a,ride.
 
Ground Roll And Climb Out RPM

Sounds pretty much like a cruise prop to me. Thing is and correct me if I'm wrong, you can re-pitch the prop to get a higher rpm on take off. Around these parts of the woods that's around $1200. Or you can get a Cato prop which seems to act like a variable pitch prop-high rpm on take off followed by cruise speeds in the 150 knot range. They're reasonably affordable at @ $3000.
High compression pistons will help generate more power with your prop as is.
 
Ground Roll And Climb Out RPM

Sounds pretty much like a cruise prop to me. Thing is and correct me if I'm wrong, you can re-pitch the prop to get a higher rpm on take off. Around these parts of the woods that's around $1200. Or you can get a Cato prop which seems to act like a variable pitch prop-high rpm on take off followed by cruise speeds in the 150 knot range. They're reasonably affordable at @ $3000.
High compression pistons will help generate more power with your prop as is.
It. all. costs. money.
 
Just switched my FP Sensi for the GA Sensi

I've been making annual June trips from Baton Rouge to AZ for the past 4 years. My plane is a 6A with a 160 hp 0320 that weighs about 1,030 lbs empty. Because of the high density altitudes in June I decided to make some changes to improve performance.

First I added Anti-splat, Lip-skid and cowl flap to add a little weight to the nose and improve cooling and safety. Then, I removed my aluminum FP Sensi and replaced it with the Composite GA Sensi. I set the pitch with the recommended number 4 gage (standard pitch). After ground testing and three short flights, here are my impressions and measurements.

1. The composite prop and hub weigh about 13.5 lbs less than the alum. prop.
2. Static RPM with the FP: 2170 rpm. With the GA prop: 2300+ rpm.
3. Initial acceleration feels much quicker.
4. I saw 1500 fpm initial climb rates and sustained rates of 1000 fpm on 90
degree day at sea level. This was with about 20 gal of gas and 250 lbs of
pilot and other stuff in the cabin. That's at least 300 fpm better than with
with the fixed prop.
5. I'm not sure about the difference in take-off run. But, I believe it's at
least 200' shorter with the new prop.
6. My top speed with both props at about 2000' is about 145 kts. This seems
to be due to the fact that I can run the new prop at 2700 rpm rather
than being limited to 2600 rpm.
7. Too soon to tell what my fuel burn will be, but it looks like I'll be running
at about 7 gph rather than 6.5+/- gph that I was getting down low with
the cruise prop.

The new prop and spinner cost me about $4000. I was able to use my old prop extension with the new prop. That's a lot of money, but much less cost and complexity than with a control pitch prop. So far, I'm very happy. And anxious to see how the upgrades work in AZ.

John
 
More Insights on Sensi GA prop

After reviewing W&B data my 6A went from 1033 lbs to 1026 lbs.

And, the CG moved from 69.3" to 70" aft of datum...

After adding Anti-splat II, Lip-Skid, Cowl Flap and changing from Sensi FP to GA prop.

The CG difference still allows for plenty of baggage and reasonably heavy PAX.

Still very pleased with improved climb and takeoff acceleration.

I experimented with a partial flap take off today. With the old prop, there was little difference between no flap and partial flap takeoffs. Taking off with partial flaps now seems to result in a noticeably shorter take off. I believe this is due to the engine getting into the best area of the power curve sooner with new prop.

John
 
BTW my prop is a 70cm6s16-0-79 sensenich metal prop 2600 max rpm range.

That’s assuming no one made any changes to it without stamping anything into it. Which sadly from what I’m told happenes quite often
 
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After reviewing W&B data my 6A went from 1033 lbs to 1026 lbs.

And, the CG moved from 69.3" to 70" aft of datum...

After adding Anti-splat II, Lip-Skid, Cowl Flap and changing from Sensi FP to GA prop.

The CG difference still allows for plenty of baggage and reasonably heavy PAX.

Still very pleased with improved climb and takeoff acceleration.

I experimented with a partial flap take off today. With the old prop, there was little difference between no flap and partial flap takeoffs. Taking off with partial flaps now seems to result in a noticeably shorter take off. I believe this is due to the engine getting into the best area of the power curve sooner with new prop.

John

This is great info because an aft CG is one of my concernes with a prop change, kind of hard to shed any weight out back.
 
Clarification

Turbo, the GA prop is about 13.5 pounds lighter. I offset about half of that weight difference by adding the Antisplat items keeping the CG shift small.

Took off from Gallup NM this afternoon. Performance was way better than when I took off from that airport at the same time last year with the old prop. The density altitude was about 2000' higher last year, but the prop made takeoff and climbout much less of a nail biter.
John
 
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jeff.i have a catto 3 blade climb prop on my 160hp 6 now you can try if you want,i picked up a whirlwind 200ga I am going to try in a couple weeks
 
Hey Howard nice to see you here.

I?d love to try that prop


My static with my prop has been 2170 the last three trips. And the last empty weight in my log books is 1096 lbs and I did the wrap since then so add approx 15 lbs to that weight.

Still trying to get my hands on scales to weight this thing.
 
I wounder if your O320 is not making full power?

You can have a metal fixed pitch prop re-pitched.

I would go through the engine and make sure compression (leak down) is good, Oil analysis is good, plugs good, air filter....
 
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