Aero Sport Power 0-375
- Thread starter ron
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john schwamm
SPONSOR
Anchorage, Alaska Carefree, AZ
Think only if Lycoming parts are used in it? Doubt that motor has any Lycoming parts?
supercub83a
SPONSOR
North Pole AK
Check out AC39-7D. ADs do not apply to experimental aircraft unless specifically stated in the AD. So it is AD dependent. A statement like “any aircraft with the model of engine installed” would make it apply.
supercub83a
SPONSOR
North Pole AK
And no part 91 operators have to comply with SBs.
If the question was more about figuring out what ADs could apply, then Im in the same boat. I have an aerosport io-375 too. It is superior cylinders and a superior case with a continental crank so I think researching the applicable ADs and SBs will require extra effort. If anyone has an easy way Id be interested.
If the question was more about figuring out what ADs could apply, then Im in the same boat. I have an aerosport io-375 too. It is superior cylinders and a superior case with a continental crank so I think researching the applicable ADs and SBs will require extra effort. If anyone has an easy way Id be interested.
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john schwamm
SPONSOR
Anchorage, Alaska Carefree, AZ
supercub83a,
Can you advise how your cub does with the i0-375? What compression pistons? Compared to stock if you had 0-320 motor in it before.
What prop do you use? Normal cruise speed? Empty weight on your cub?
Thanks,
John
supercub83a
SPONSOR
North Pole AK
My io-375 has 9:1 compressions, superior cold air induction, e-mags, and the hartzell trailblazer 83” prop. Its the only engine that I’ve had on this plane. The plane weighs 1274 with belly pod and slats on 35s. Before the slats and pod it was 1225 (with 8qts of oil in the sump). It has an amazing amount of acceleration, everyone that rides comments on it. Before slats and pod at 75% power and 3500ft it would do 120-125 indicated. 65% would get you about 105-110 and 55% about 95-100. Thats on 35s. Fuel consumption at 75% was over 12gph but at 55-65% and lean of peak im getting 6.5-7.5 gph.
My last cub was an o-320 160hp, with a borer prop pitched to 82-47. It was on 31s and weighed 1191 on wheels. Previous owner had pitched it to a cruise prop, but it would still get over 2400 rpm static. At 2400 rpm it would cruise around 90-95 and burned a little less than 7.5gph. Its harder to have more precise and accurate numbers for it because it lacked the instrumentation to measure.
Conclusion is that the io-375 lean of peak on 35s gets slightly better fuel economy than the o-320 did on 31s for the same indicated airspeed. Overall fuel consumption is higher on the 375 (burns a lot more down low and rich). The acceleration on takeoff I can only measure subjectively, but it seems to be about 50% greater than the previous cub despite that cub being almost 100lbs lighter. The plane is; however, very nose heavy. Not a problem if you fly with tons of gear, but maybe not the greatest handling when lite.
The engine prop combo was by far the biggest upgrade made from the last cub. Slats were the 2nd biggest. G3x system and modern suspension tied for third.
My last cub was an o-320 160hp, with a borer prop pitched to 82-47. It was on 31s and weighed 1191 on wheels. Previous owner had pitched it to a cruise prop, but it would still get over 2400 rpm static. At 2400 rpm it would cruise around 90-95 and burned a little less than 7.5gph. Its harder to have more precise and accurate numbers for it because it lacked the instrumentation to measure.
Conclusion is that the io-375 lean of peak on 35s gets slightly better fuel economy than the o-320 did on 31s for the same indicated airspeed. Overall fuel consumption is higher on the 375 (burns a lot more down low and rich). The acceleration on takeoff I can only measure subjectively, but it seems to be about 50% greater than the previous cub despite that cub being almost 100lbs lighter. The plane is; however, very nose heavy. Not a problem if you fly with tons of gear, but maybe not the greatest handling when lite.
The engine prop combo was by far the biggest upgrade made from the last cub. Slats were the 2nd biggest. G3x system and modern suspension tied for third.
BC12D-4-85
SPONSOR
Fairbanks, AK.
83a....next build a sub 1K Cub with 160. Feel the power in a light frame as we've talked for short ops?
Gary
Gary
john schwamm
SPONSOR
Anchorage, Alaska Carefree, AZ
Great info, thanks for the reply.
supercub83a
SPONSOR
North Pole AK
N
Flying a sub 1K carbon cub with the redesigned ailerons and a 180horse stroker engine is probably the most joyful flying plane I have flown. I think at light weight it would outperform the heavier/higher hp cubs. I really cant imagine it hauling half a moose out of a shorter, rougher strip than the SQs and o375 cubs with massive flaps and slats though. I may go the ultra light cub route on the next build regardless, maybe a carbon cub or another javron. That may hinge on cubcrafters new ELAS system availability on the carbon cubs, very interested in that system.
Steve Pierce
BENEFACTOR
Graham, TX
I would like to know more about this airplane.
The FAA places no mandate on an engine for an experimental aircraft to conform to a type certificate. Yet AD's and SB's are good information for the EAB builder to consult. Is anyone in authority thinking your engine must conform to a type certificate?
I made up a list of serial numbers of parts that I know are in my lycoming based engine that is going in my experimental aircraft. We don't want to use parts that have known issues.
supercub83a
SPONSOR
North Pole AK
It was an EX-2 I flew at the factory when the EX2 was fairly new. Flew it about an hour and did 8-10 landings in it. Had the CC-340 engine. Claimed the weight was 9** something and 180hp. I do know that it handled and performed like none of the cubs I had flown up to that point. I still think my current cub would out lift it, but it doesnt handle as nicely. At least to the best of my recollection….
How’re your CHT’s?
Our Aerosport IO375 w/ 7.8:1 pistons and same induction + mags (running on A curve) as yours has trouble keeping CHT’s down below 400 unless I’m absolutely lean of peak @ 60% power or increase fuel flow to 9-9.5 gph @ 60% power.
We’ve done a bunch of baffling and other “tune-ups” to help a bit, but it sure doesn’t run as cool as our Conti 520’s! I suspect the XL cargo pod, slats, PStol flaps and 31’s hanging out there making for 85mph economy cruise isn’t helping with the cooling. The pod definitely increases CHT’s across all cylinders.
supercub83a
SPONSOR
North Pole AK
I think a little hotter temps are expected with supercubs running big tires, slats and big engines. Mine routinely goes over 400 in climbs during the summer when loaded. It will get to 430 to 440 if I let it. In cruise I run about 380-390, lean of peak at 6.5-7.5gph. That gets me 80-90mph. I have to be rich of peak by about 150-200 degrees to keep everything less than 400. I would have to look at my data but I believe that is roughly 10.5 gph. I will probably try to adjust my lower cowl or add louvers this winter to see if I can get it a little cooler but I consider it acceptable now. It does run cooler than my last certified cub with an o-320, I tried for two years to get it cooler, never could figure out how. It had port polished continental eci nickel cylinders.
The slats made a signifiant increase in temps. I also have a belly pod.
What is your bottom cowl like? Adding a cowl lip to my bottom cowl had a huge impact, approximately 10 deg per cylinder and my oil temp dropped 15-20 deg.
The slats made a signifiant increase in temps. I also have a belly pod.
What is your bottom cowl like? Adding a cowl lip to my bottom cowl had a huge impact, approximately 10 deg per cylinder and my oil temp dropped 15-20 deg.
skywagon8a
MEMBER
SE Mass MA6
You may have better outlet airflow if that cowl lip was angled back more. 45 degrees or so. The way it is now, the air flowing around the outside swirls up behind the lip creating an "air dam". This could actually restrict the outflow of the engine cooling air.
tedwaltman1
BENEFACTOR
Delta, CO
SuperCub83a, I clearly need your advice, both on what modifications I must do to my SQ-2 as well as your thoughts on perhaps changing my prop. I have a constant speed Whirlwind. Same IO-375 engine. While my empty weight on 35”s is slightly higher, it’s not enough to be significant. I too have a cargo pod & slats. Hence, at first glance seemingly a very comparably configured Super Cub. Std flaps, not PSTOL flaps.
At 75% power, 6,000’ field elevation, I have never seen more than 98 indicated. 120 to 125 as you report—no way no how, not even close.
Your prop might make some difference, but surely not 20++ mph difference.
What am I doing wrong?
At 75% power, 6,000’ field elevation, I have never seen more than 98 indicated. 120 to 125 as you report—no way no how, not even close.
Your prop might make some difference, but surely not 20++ mph difference.
What am I doing wrong?
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supercub83a
SPONSOR
North Pole AK
Your upper safety cables tab should be attached at the gear leg bolt tab. Not the Cabana V tab.
DENNY
Good point. Unfortunately, that is the way Legend fashions the lower cowling piece. I’ll fab a temporary wedge and attach to see if it helps.
There’s no doubt that the 4” deeper experimental cargo pod disaffects the cooling and cruise speed. Were I to do it over again, I would replace with standard pod.
skywagon8a
MEMBER
SE Mass MA6
When Cessna supplied the optional belly pod on the 180/185s, they also installed cowl flap extenders. On one plane (I think the Cessna 140) there was a rolled (2" +/-) piece of aluminum mounted to the bottom of the firewall which helped produce a venturi effect to suck more air through the engine. I've also seen lips mounted to the side cowls to pull more air out that opening. It was ugly though.
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supercub83a
SPONSOR
North Pole AK
Already fixed, realized I did that a few months ago.
You ever try lead shot in the horn at the bottom of the rudder to help with the extra weight on the nose? I've heard you can get approx 7 lbs in the aluminum fork at the bottom of the rudder.... or, potentially up to 6 lbs of antifreeze in a baby bushwheel without losing cushion? I took off a 320 and put on a IO-375 and a CS prop and gained enough that I run out of elevator without power. Few perfectly before adding the extra weight (even loaded with a passenger), and am likely going to counter it with some weight in the tail. Thoughts?
BC12D-4-85
SPONSOR
Fairbanks, AK.
I'd consider a composite fuel tank aft - somewhere. Transfer to adjust CG. Fuel can be used unlike lead.
Gary
Gary
tackdog
MEMBER
Wagga Wagga Australia
Hi Johnny, I've been thinking of following this path for my oil cooler - do you have a picture of how the hood scoop connects to you SCAT tubes to feed air to your oil coolers please? I was wondering if a large naca scoop underneath the scoop would do the job....
I take it you run out of elevator during landing. Where is your trim set? I would not add weight unless you have run out of trim, gap seal in the tail will help also.
DENNY
bob turner
Registered User
How do you get 7 lbs in that rudder arm? We just brought a Champ in that needs about 9 lbs at the tail. It was a surprise - similaraircraft hit the scales ten lbs heavier in the tail.
It flies fine, and lands fine. But with full fuel and a 200 lb pilot it is slightly out forward. I trust the last weigh-in and can duplicate the computations.
It flies fine, and lands fine. But with full fuel and a 200 lb pilot it is slightly out forward. I trust the last weigh-in and can duplicate the computations.
BC12D-4-85
SPONSOR
Fairbanks, AK.
Citabrias had a big battery behind the baggage to balance CG. Some (like me) either replaced it with lighter or moved it forward next to the firewall. I wanted extended baggage so moved it. CG then required aft weight.
Gary
Gary
I am south for a few months so can't take pics. Suggest you call Legend Aircraft in Sulphur Springs TX to discuss. They may be able to hook you up with a build diagram or even sell you the scoop + outlets. It's a pretty simple design.
How's that 83" Trailblazer working for you? 2-blade?
For our PA-18 clone, we have an Aerosport IO375 with 7.8:1 pistons that dyno'd @ 187HP. I'm considering pulling the 82" Sensenich STOL prop and putting on a constant speed 2-blade Trailblazer (80 or 83"). We built the engine with hollow crank and front-mount governor pad so I could easily upgrade in the future.
Would like more uumph on short field takeoffs, then higher cruise speeds to cool the cylinders. I also wouldn't complain about the weight on the nose because we're frequently at gross weight and I'd like the CG to come forward.
