# 18hp + Nitrous , for higher altitude

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#### Bille Floyd

##### Well-Known Member
There are a few 170 cc, twin apposed engines on the market, that can put out
near 18-hp ; and only weigh under 10-Lb's, (add a bit, for a reduction) and E-start.

My Exxtacy glider will fly quite nicely on that hp rating, with good
climb at sea- level ; won't be enough at 5,500 ASL though.

SO the question is :
Would a bit of Nitrous + water , help keep my hp at 6k ASL ? I don't want
more hp ; just want to keep the hp, for what the engine was rated for, at sea
level , (when i'm at a higher elevation) ?

Bille

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#### proppastie

##### Well-Known Member
Log Member
How many would you blow up before you figured out the proper amount. .,........Would a small electric blower/super-charger work better? Some high grade engine theory to answer on paper.
Maybe just catch a good thermal....Part 103 limited to 10,000 ft I think.

#### pictsidhe

##### Well-Known Member
Pt103 has no altitude limit. Could get tricky getting permission for class A, though.
If adding power, you must consider cooling. Low density air does not cool as well. A bigger radiator fixes this for water cooled, but air cooled is harder.
The nitrous tank for much time is likely to be heavy.

#### dog

##### Well-Known Member
there are a lot of very small and light turbos
I am playing with the same idea for a continental
170cu inch

#### proppastie

##### Well-Known Member
Log Member
Pt103 has no altitude limi

oops .....Part 103 wins again

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Sport Pilots are allowed to fly to an altitude of 10,000 feet above mean sea level, or 2,000 feet above ground level, whichever is higher. Sport Pilots are allowed to operate in Class E and G Airspace.

#### Bille Floyd

##### Well-Known Member
...
Maybe just catch a good thermal....
...
That's the entire Point ,for using the engine , with a folding prop ; get
high enough , to catch the thermal , in the first place !

I do Not like motoring around ; i will put up with an engine, to get in position
for the real mission , (Soaring) .

Bille

#### dog

##### Well-Known Member
That's the entire Point ,for using the engine , with a folding prop ; get
high enough , to catch the thermal , in the first place !

I do Not like motoring around ; i will put up with an engine, to get in position
for the real mission , (Soaring) .

Bille
Very good.
but.two options is number one or
you need to have the motor put up with you as well.
and that means taking a deep breath and gett to know it and its limitations ,and if you are going
to experiment,well then,you are now officialy a gear head.no getting around it.nitrous and alcohol
injection and gasoline and full power, your a gear
head, welcome to the eternal quest for more zoom

#### sotaro

##### Well-Known Member
there are a lot of very small and light turbos
I am playing with the same idea for a continental
170cu inch
Actually, I don't think there are any turbos that would work for a 170cc engine, at least not in an efficient range.

#### proppastie

##### Well-Known Member
Log Member
My 3W-200 (200cc) has a 12 mm crank, does not inspire confidence. That it is on a glider is the only saving grace. Hopefully I will be ether low enough to put it back down or high enough to turn around if there is a problem.

#### Victor Bravo

##### Well-Known Member
Ain't no replacement for displacement. In order to get 18HP at 5000 density altitude you may need a 25-30HP "nominal" engine. There are plenty of paramotor engines that are state of the art, that come complete with redrive, starter, etc. Some of these would be a bolt-on proposition.

#### Bille Floyd

##### Well-Known Member
...
In order to get 18HP at 5000 density altitude you may need a 25-30HP "nominal" engine. There are plenty of paramotor engines that are state of the art, that come complete with redrive, starter, ...
That is exactly what John said ; the owner of the airport, at the base
of King mountain.
I can pick up a new Moster 185 plus, with redrive clutch and starter
for about \$3K ; so it's hard to argue with what ya just said !

Given a choice , I would prefer, a twin apposed , over a single cylinder
thumper ; they run a lot smoother. I wonder how big the crank is on the Moster ?

Bille

#### Bille Floyd

##### Well-Known Member
Actually, I don't think there are any turbos that would work for a 170cc engine, at least not in an efficient range.
"dog" said that he was working on it ; and i would be Very interested in
his progress !!!!!

@ proppastie :
What do you have your 3W-200 , bolted to ; any pictures ?

#### dog

##### Well-Known Member
working on a 170 cu inch motor, hoping to get a bit more power in the take off run, as the base motor is 65hp and is marginal, like my budget,
got turbos, a-65 parts are reasonable.
I also have become interested in smaller lighter aircraft from listening here on HBA, though my
part of the world is meteorologicaly challenging
and carrying a bit of weight is helpfull in when things get rough suddenly

#### eta1046057

##### New Member
There are a few 170 cc, twin apposed engines on the market, that can put out
near 18-hp ; and only weigh under 10-Lb's, (add a bit, for a reduction) and E-start.

My Exxtacy glider will fly quite nicely on that hp rating, with good
climb at sea- level ; won't be enough at 5,500 ASL though.

SO the question is :
Would a bit of Nitrous + water , help keep my hp at 6k ASL ? I don't want
more hp ; just want to keep the hp, for what the engine was rated for, at sea
level , (when i'm at a higher elevation) ?

Bille
It's Methanol and water

#### proppastie

##### Well-Known Member
Log Member
I would prefer, a twin apposed , over a single cylinder
thumper ; they run a lot smoother
not at idle.....watch when I turn it off.

#### poormansairforce

##### Well-Known Member
"dog" said that he was working on it ; and i would be Very interested in
his progress !!!!!
I think you missed the size of his engine...170 cubic inches.

#### Bille Floyd

##### Well-Known Member
I think you missed the size ...
OOPS -- Yea , i think i "Wanted" to see 170cc !

Bille

#### Bille Floyd

##### Well-Known Member
not at idle.....watch when I turn it off.

...
What causes that ?
The guys with twin's at Bennett RC field ; there engines run smoother, for some
reason. Is your engine broken in ; what size prop, and did you balance it
because i saw 1931 rpm on your tach

From : 3w-200 twin -- What rpms? - RCU Forums

rcuniverse said:
...
I would suggest a 32x10 or 30x12 prop , which should adjust the engine into the 6000 - 6500 rpm range.
My Grandpa , had a tractor, just like yours ; i can still smell the tobacco !!

Bille

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#### Bille Floyd

##### Well-Known Member
...
That it is on a glider is the only saving grace. Hopefully I will be ether low enough to put it back down or high enough to turn around if there is a problem.
Your 100% correct , on that !!!

In Normal thermaling , if i want to reverse direction in a thermal , i
reduce the flap setting from 20-deg, to 5-deg and speed up to
35-mph ; i now have the energy to exit the thermal , and reverse
direction , with usually no more than a 10 to 20-ft altitude loose .
Then the flap goes back to 20-degrees down ; for min-sink speed.
Bin doing that for 20 years on the same machine ; the numbers
are close.

#### proppastie

##### Well-Known Member
Log Member
What causes that ?
The guys with twin's at Bennett RC field ; there engines run smoother, for some
reason. Is your engine broken in ; what size prop, and did you balance it
because i saw 1931 rpm on your tach
It is a 32-10, and a boxer, both cylinders fire at once.....I think I got to 5000 rpm, and no the engine is not broken in.... It idles at about 2000 very rough but I do not plan to stay at that rpm......nice thing about the model engines..... the props are fairly reasonable in price, so I expect to change it, thanks for the link and advise on props

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