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Ground roll and climb out RPM?

Just did an annual and compressions are 78/80 or better. Cold.

Static rpm is good for the prop I have I think I?m just heavy. Both me and the airplane. Lol
 
Block, cant wait to hear about how that Whirlwind performs!

Haven?t seen H. Block in a while on the ground or in cyber space. Hoping we?ll catch up soon now that I?m flying again and I can try that prop. I?ll keep you guys updated as I try anything new.
 
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.



I think you may be on to something w the carb. I have a 10-5009 carb that has had some work done but I feel it?s probably still lean at WOT.

Your the first person I?ve heard of that takes off with more than 10 degrees flaps. My (instructor) for transition training told me never to go above 10 deg. Anyone else use more flaps?
 
After i rebuilt my engine with 10-1 pistons, port/polish cylinders, dual pmags and rv200 cs prop, i was way too lean. I drilled the main jet to #37. It was a #42. I can climb wot to 10000ft with no overheating. Oat was 40 degs yesterday and i was climbing 2300 fpm at 90knots. My engine is putting out 180+hp now.

Check your carb jetting. They are notorious for being too lean in the vans airbox setup. I would suggest a #38 to start with. Mine is a little rich when really hot outside, but runs perfect when cooler. I would rather have the extra flow when the oat is 100 degs.
 
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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.
Do your top speed at full throttle and report RPM, speed and total AC weight. Also report density altitude, and if able fly lower (safely), say 1000 feet agl. To get accurate speed do a GPS speed triangle flying tree headings 120 degree apart and record each leg's ground speed. Average the three (not super accurate but good enough). Your AS indicator may be off. You should get TRUE airspeed near +190mph if you are making near 160 HP your prop is pitched right. You should see over 2700 RPM (but do not exceed 2850 RPM). Red Line RPM is 2700 RPM, but you have 5% to play with.

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?
I would not compare it to your friends plane. What is the compression of your engine?
Type of exhaust, crossover two into two?
Do you have Vans FAB with K&N filter, clean, not old and tired.
Plugs looking normal not too lean?
What is your total AC gross weight?
What is your ROC?

What I am driving at is your 160HP engine might be making 150 or 140 HP.
 
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NO. The metal prop for an O-320 is redlined at 2600 RPM rpm. Do not overspeed it.

This is correct airplane is placarded at 2600 do not exceed and it?s in the log book as well.

It willl exceed this at WOT if I let it so too speed WOT is out of the question.
Something yo remember here is my runway is 2100 ft with trees on both ends. So what might be good climb out on a runway of 4000 or 6000 ft is not gonna cut it here.

I looked at the log book from when it was first built and the static on the ground holding the brakes was far higher. 200rpm or so. This was two props and two rebuilds ago though. Both by previous owners . The good news is the engine is only at 277 hrs and compressions are good. Oil in changes is clean as a whistle .
Bad news is it?s had a burble issue with the 10-5009 that has been chased since it was built. Switched to a
One piece Venturi But I don?t know what?s in it for a nozzle.
The burble is mostly on transitions from climb to cruise and vice versa.
 
I would not compare it to your friends plane. What is the compression of your engine? I dio not know for sure the compression seller told me it was a
160 hp can’t find any notes in log book.

Type of exhaust, crossover two into two? Vetteran exhaust x over.

Do you have Vans FAB with K&N filter, clean, not old and tired. Yes vans fab clean at every annual, filter is older, I have a new one I could test but was waiting to change carb before swapping because mine has a bulge that the cleaner is cut for and not sure the next one will.
Plugs looking normal not too lean? Plugs have looked pretty good in fact I think we changed the lowers because they were on the rich side and a little lead on them last annual. ( But I put around a lot at low rpm sightseeing lol )
What is your total AC gross weight? Empty weight is 1140 or something it’s in this thread somewhere and I’m
Between 220 and 230 most of the time pax are a range obviously

Don’t know the rate of climb - I look at the gauges when I level off. On climb out (at least initial I’m focused on airspeed and altimeter but not rate)

Ground roll to 65 -70 mph pop up level off til between 90 and 100 then pitch up for 100 climb if it’ll do it. (Before trees) Anything under 100 mph chts suffer and I like to keep cyl cool.

Alamost always fly w fuel
1
Inch below the tank rims on take off. It’s just how I fill it when I land typically.
 
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http://gikonfly.blogspot.com/2009/01/lean-carb-enlarge-that-jet.html

Here is a link to a carb jetting article that is specific the rv’s.

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That is a very interesting article. I will say I have a fixed pitch prop so that?s different and I don?t see any high temps on the ground , it doesn?t hard start, plugs have been pretty good.
However my baffling from the lower cowl to the carb were worn and leaking and since I replaced it with cowl saver material and a VERY tight fit I feel the stumble/ burble were far more pronounced, though I only flew it one time with about 6 T/O and landings.
These are new mags last year, and timing was checked / plugs cleaned and checked right before this flight. Compressions were also checked and all
Looked good as this was right after my annual inspection.

Only change was a check of pushrod length and two rods being replaced (to center them in length spec) as well as the upgraded baffling around the fab and inlet.
 
On the side of your carb is a small metal plate with three holes. This is the accelerator pump adjustment. Start in the middle hole and put it another hole until it runs smooth when advancing the throttle. My engine will stumble just a little when the OAT is hot and does perfect when the temps are cold outside. This tells me i am to rich on the pump adjustment. The denser cold air will take the extra gas. I am going to adjust it at next oil change.
 
On the side of your carb is a small metal plate with three holes. This is the accelerator pump adjustment. Start in the middle hole and put it another hole until it runs smooth when advancing the throttle. My engine will stumble just a little when the OAT is hot and does perfect when the temps are cold outside. This tells me i am to rich on the pump adjustment. The denser cold air will take the extra gas. I am going to adjust it at next oil change.

I’ll try that but Fred Stucklen ( previous owner ) made all kinds of mods to this thing years ago and never could get it to go away. It’s also when you pull back the throttle coming into a pattern as well or at the top of climb when you pull back so it’s not just when advancing the throttle although that is the part I’m more concerned with right now .
 
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Anyone have thoughts on Ellison or other EFI or MFI or carb type options? Want to make the right choice if I swap it out.
It?s flown like this for a very long time and it?s been reliable but much like others have reported it? can make passengers a little nervous and it?s definitely worse with the better baffle material and proper seal
 
I’ll try that but Fred Stucklen ( previous owner ) made all kinds of mods to this thing years ago and never could get it to go away. It’s also when you pull back the throttle coming into a pattern as well or at the top of climb when you pull back so it’s not just when advancing the throttle although that is the part I’m more concerned with right now .

Do some research on the difference between a rich stumble (possibly the burble you describe) and a lean bog. You can be either under enriched or over enriched on your acceleration. The difference is easy to differentiate once you understand them. Determine which it is first and then adjust the accel pump lever accordingly. The holes that offer more leverage (typically the ones closer to the arm and further from the pivot), deliver more fuel during throttle advance (i.e. richer transition).

What rpm are you decellerating to when you have the stumble? If it is 1200 or below, you may be able to address that with your idle mixture. When decelerating to lower RPMs, the idle mixture can cause these type of problems.

Larry
 
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Do some research on the difference between a rich stumble (possibly the burble you describe) and a lean bog. You can be either under enriched or over enriched on your acceleration. The difference is easy to differentiate once you understand them. Determine which it is first and then adjust the accel pump lever accordingly. The holes that offer more leverage (typically the ones closer to the arm and further from the pivot), deliver more fuel during throttle advance (i.e. richer transition).

What rpm are you decellerating to when you have the stumble? If it is 1200 or below, you may be able to address that with your idle mixture. When decelerating to lower RPMs, the idle mixture can cause these type of problems.

Larry

I appreciate the post, the main burble is something people o. Here have had issues with for years. Done major mods to the 10-5009 carb and even changed it to a 10-5009N with the pepper pot nozzle and still carbs that have it still cannot seem to shake it.
I?m
Am ex drag racer since 1987 so I?m fairly familiar with carbs having run everything from Q jets to Holley to SA carbs on my MGA. Although I haven?t done anything with this one. Mainly because so really good carb shops have done these and not been able to resolve the issues and Fred is a VERY thourough person and he couldn?t resolve it. And I know he changed to a 1 piece Venturi and everything . So I?m sure he tried that
But I?ll give it a go anyway because one thing drag racing has taught me is never say never. Lol

But being so many people have had this issue and it seems to be something in the casting I may be changing carb bodies
 
I appreciate the post, the main burble is something people o. Here have had issues with for years. Done major mods to the 10-5009 carb and even changed it to a 10-5009N with the pepper pot nozzle and still carbs that have it still cannot seem to shake it.
I’m
Am ex drag racer since 1987 so I’m fairly familiar with carbs having run everything from Q jets to Holley to SA carbs on my MGA. Although I haven’t done anything with this one. Mainly because so really good carb shops have done these and not been able to resolve the issues and Fred is a VERY thourough person and he couldn’t resolve it. And I know he changed to a 1 piece Venturi and everything . So I’m sure he tried that
But I’ll give it a go anyway because one thing drag racing has taught me is never say never. Lol

But being so many people have had this issue and it seems to be something in the casting I may be changing carb bodies

Best of luck with it. It may be something with that model. I had a 3270 and never had any issues like that and it even had the 2 piece venturi. Have you checked the float level? There have been several ADs on those floats and I expect many people putting them in don't know they have to verify and likely set the float level after installing them. As you know, a 32nd or a 16th makes a big difference. Worse in aviation, as some of it's effects can be offset via the mixture knob, but will be ugly in transitions or lower RPM, as well as full rich settings. Although, if the 5009N was new or rebuilt, I would expect that is not the issue.

Good luck.

Larry
 
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Best of luck with it. It may be something with that model. I had a 3270 and never had any issues like that and it even had the 2 piece venturi. Have you checked the float level? There have been several ADs on those floats and I expect many people putting them in don't know they have to verify and likely set the float level after installing them. As you know, a 32nd or a 16th makes a big difference. Worse in aviation, as some of it's effects can be offset via the mixture knob, but will be ugly in transitions or lower RPM, as well as full rich settings. Although, if the 5009N was new or rebuilt, I would expect that is not the issue.

Good luck.




Larry


Thanks for the suggestions I'll look into all these items when I get it apart. Really want to get this sorted out. To many people it probably wouldn't be as big a deal but as an ex racer and engine builder I really like things to run properly. I'm not as likely to dig into this as with the cars (I like big turbos on those ) but it'll probably happen sooner than later.who knows maybe this will see a turbo soon too.
And not a turbo normalized set up but more like 1 bar of boost or more for a little power. Im actually very surprised I don't see turbo kits for these engines yet.

They are very reliable if set up properly to, I have 9 years at 1000 hp on my set up without even changing a spark plug.
designed and built the whole set up myself too.

Sadly once I dig into this thing I feel I won't be able to stop lol.
 
So flew the airplane today and it was a slightly warmer day today. Oddly I ran the airplane w car. Heat and stumble on applying power was worse so I leaned it and it went away so it?s a rich stumble.

I couldn?t duplicate the stumble on pulling back the throttle in the pattern no matter what I did.

Climb rate w me alone in the airplane between zero and 100 ft agl was below 500 ft per minute at approx 80 90 mph. Hit 100 mph and it jumped up to 800 ft per minute as it climbed mph to 110 to 120 mph it hit 1000 ft per minute or more. 6 take offs and landings all similar but leaning the mixture somewhat improved the take off roll distance . Exactly opposite what I?d have expected

Chts never went above 380 even if I pulled the nose up and climbed at 90 mph when slightly leaned.

Throttle response as checked on the ground when I?d push the throttle in quickly was much better ( dare I say perfect ) when leaned.
 
I went through thread but how do your plugs look.

Plugs looked good in fact had a little lead fouling which I felt was contradictory to the lean stumble I thought I was having.
Turns out it’s probably in line with rich stumble.

I watched a take off video of a
Bunch of vans aircraft today on YouTube and don’t feel they climbed out any different than mine.
And I feel like leaning it greatly improved it’s take off climb
Of course I was alone on that test flight. True measure will be a flight w passengers.

This is probably similar to my take off angle.


https://youtu.be/na2pxJCKeUs
 
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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

So my airplane is about 100 lbs heavier than yours and I’m about 50 lbs heavier so me alone is like you having a faa standard size passenger. Lol
 
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Dave Anders figured that max climb would increase about 1 fpm for every pound removed from the plane.

You mentioned that the motor was rebuilt. If the cam was installed one tooth off, it would greatly effect the performance. This will not show up during a differential pressure test. But you might be able to see it with a COMPRESSION test.
 
Plugs looked good in fact had a little lead fouling which I felt was contradictory to the lean stumble I thought I was having.
Turns out it’s probably in line with rich stumble.

I watched a take off video of a
Bunch of vans aircraft today on YouTube and don’t feel they climbed out any different than mine.
And I feel like leaning it greatly improved it’s take off climb
Of course I was alone on that test flight. True measure will be a flight w passengers.

This is probably similar to my take off angle.


https://youtu.be/na2pxJCKeUs

each engine is different, however, I lean for take off and climb. Servo is simply too rich for my setup (FP). I also have a noticeable improvement in power/RPM by doing this. I have a standard I used for take off and need to enrich a bit as I taper off the climb AOA and the engine speeds up accordingly (RPMs come up, requiring more fuel). Yes, I have taken away some detonation margin by climbing at 125-150 ROP, but my engines cools well and personally have no issues with the approach. Just providing a data point, not a recommendation.

Larry
 
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When you pulled the plugs, did all the plugs look exactly the same or did you notice 2 cylinders/plugs were running more rich than the other two?
 
It?s been a while but previously there were two plugs richer. All looked pretty rich. We changed half the plugs to keep them from building up lead.
 
each engine is different, however, I lean for take off and climb. Servo is simply too rich for my setup (FP). I also have a noticeable improvement in power/RPM by doing this. I have a standard I used for take off and need to enrich a bit as I taper off the climb AOA and the engine speeds up accordingly (RPMs come up, requiring more fuel). Yes, I have taken away some detonation margin by climbing at 125-150 ROP, but my engines cools well and personally have no issues with the approach. Just providing a data point, not a recommendation.

Larry

Leaning definitely helped but I didn’t lean it through much and it’s CHTs got better which surprised me.

I leaned it about 1/4 inch out. So far for actual take offs
 
Dave Anders figured that max climb would increase about 1 fpm for every pound removed from the plane.

You mentioned that the motor was rebuilt. If the cam was installed one tooth off, it would greatly effect the performance. This will not show up during a differential pressure test. But you might be able to see it with a COMPRESSION test.

Conpressions have always been approx 78/80 though I think this past annual one was 76/80
 
So just a quick update, I always felt there was an issue and I kept searching and searching. One thing I've asked a&ps who looked at or worked on my airplane for years was why my fuel pressure fluctuated. No rhyme or reason sometimes it would just show low. No one could ever find anything.

So during this past annual. I decided to flip on my boost pump while my air box was off, because there was the slightest staining of fuel between my air box to carb mounting plate.
Sure enough the cover for the accelerator pump was leaking when under pressure. It was leaking (weeping) into the carb hat soaking the air filter so it wasn't noticed, I took it apart straightened the cover (bowed like exhaust flanges get from over tightening) put a new gasket on it and sure enough fuel pressure is now rock solid. (Years I've been chasing this fluctuation)
On top of that the airplane appears to have better climb out. This would also explain why the airplane proved to be rich and needed to be leaned on takeoff when many are just the opposite.
I can't be sure of the takeoff performance comparison, because it also dropped about 20 degrees at the same time I found this issue, but it certainly seems to have made a difference at this point.

Just wanted to post because if your gut tells you there's an issue and 4 a&ps tell you there's nothing, keep looking your gut is probably right.
 
Off topic

Just looked at the pictures of your plane and the vinyl wrap looks great. Did you have a helper or were you able to handle the vinyl sheets single handed? You really improved the appearance of your plane, great job!
 
Just looked at the pictures of your plane and the vinyl wrap looks great. Did you have a helper or were you able to handle the vinyl sheets single handed? You really improved the appearance of your plane, great job!
Thanks for the compliment-
Did the whole thing by myself.
Have assisted a few more since then, I used to paint custom cars but can’t use two part paints anymore. So I decided to swap over to vinyl. I like it a lot it doesn’t chip like paint which is nice. More forgiving that way. And if you have an issue you can heat remove and reapply a section. You know it’ll match if you order extra .
One thing people don’t realize is it has to be perfect underneath the vinyl because it will show anything under it. If there’s a hair under that vinyl you’ll see it. The only thing I’d suggest is putting a ceramic coating on top for added protection. Helps with bugs any staining from exhaust /heat etc.
 
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