Maximizing Power in Nitro 2 Stroke Engines: A Question on Crankcase Size

  • Thread starter THORPE
  • Start date
  • Tags
    Power
In summary: Additionally, the increased internal volume of the crankcase would also result in a higher compression ratio. So while it may not have an overall increase in power, it would certainly make the engine more efficient and achieve the same power with less fuel.
  • #1
THORPE
41
0
Quick questions but want to let everyone know up front I'm no physics expert I just think ALOT. :)

I understand that a small nitro 2 stroke engine (RC cars) pulls the fuel into the crankcase when the piston is on it's up stroke.
I am curious if say I developed a way to make the crankcase larger during the intake stroke and smaller during the down stroke (when it pushes A/F into the combustion chamber), Would there be any added power benefit?

It would seem to have more volume to suck fuel and less volume to compress it to the cylinder equaling more HP.
 
Engineering news on Phys.org
  • #2
THORPE said:
Quick questions but want to let everyone know up front I'm no physics expert I just think ALOT. :)

I understand that a small nitro 2 stroke engine (RC cars) pulls the fuel into the crankcase when the piston is on it's up stroke.
I am curious if say I developed a way to make the crankcase larger during the intake stroke and smaller during the down stroke (when it pushes A/F into the combustion chamber), Would there be any added power benefit?

It would seem to have more volume to suck fuel and less volume to compress it to the cylinder equaling more HP.

After research I've answered my own question.
You can't charge the cylinder anymore than normal because the exhaust port is open longer than the intake on these style engines.

The only way to get more cylinder fill is with tuned exhaust to reflect some of the mixture back into the cylinder before the port is closed.

I'm sure there is a way to redesign it with valves but it would probably fail to support the high rpms these engines produce (30-40,000rpm) and would be heavier and more complicated.
 
  • #3
The internal volume of the crankcase vs the displacement of the piston as it comes down determines the crankcase compression ratio and will affect the power output for several reasons.
 
  • #4
mender said:
The internal volume of the crankcase vs the displacement of the piston as it comes down determines the crankcase compression ratio and will affect the power output for several reasons.

Ok so it may be worth a shot?

I was under the assumption that it would not be feasible much like turbo charging or super charging with sleeve port engines doesn't work.

Seems the only way to get benefits is to come up with a way to get the exhaust port to open first to let exhaust out and also close first so you don't lose the added fuel & air brought into the crankcase then forced into the cylinder.
 
  • #5
It's more for tuning the power curve than for an increase across the board.

Using the tuned pipe is effectively a way to close the exhaust valve earlier in that it inhibits further flow as well as the mild charging effect that was noted.
 

1. What is a 2 stroke engine and how does it work?

A 2 stroke engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston (compared to four strokes in a 4 stroke engine). It works by compressing a mixture of fuel and air in the combustion chamber, igniting it with a spark plug, and releasing the exhaust gases through the exhaust port. The downward motion of the piston creates the power that drives the engine.

2. How does adding power to a 2 stroke engine work?

Adding power to a 2 stroke engine typically involves making modifications to the engine's intake, exhaust, and fuel delivery systems. This can include installing a larger carburetor, upgrading to a high-performance exhaust system, and adjusting the engine's timing and jetting. These modifications allow for more air and fuel to enter the engine, resulting in increased power output.

3. What are the benefits of adding power to a 2 stroke engine?

The main benefit of adding power to a 2 stroke engine is increased performance. This can result in higher top speeds, quicker acceleration, and more torque. Additionally, adding power can also improve the engine's fuel efficiency and reduce emissions.

4. Are there any drawbacks to adding power to a 2 stroke engine?

One potential drawback of adding power to a 2 stroke engine is that it can put more stress on the engine's components, potentially leading to increased wear and tear. Additionally, depending on the modifications made, the engine may require more frequent maintenance and tuning to maintain optimal performance.

5. What types of vehicles use 2 stroke engines and added power?

2 stroke engines and added power are commonly found in smaller vehicles such as scooters, dirt bikes, and small boats. However, they can also be used in larger vehicles such as snowmobiles, jet skis, and some motorcycles. These types of vehicles typically require high levels of power and performance, making them ideal candidates for added power modifications.

Similar threads

How does a 4-piston, 4 stroke internal combustion engine work?
    • Mechanical Engineering
Replies
11
Views
2K
Automotive Loss of gaseous volume because of fuel combustion
    • Mechanical Engineering
Replies
2
Views
199
On-demand steam engine idea
    • Mechanical Engineering
Replies
1
Views
72
Engineering Evaluate 2-stroke & 4-stroke Diesel engines therm & mechanical efficiency
    • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
IC Engine Question -- Starting sequence for 4-stroke engine
    • Mechanical Engineering
Replies
10
Views
2K
Could a Reverse Uni-Flow Engine Revolutionize the Automotive Industry?
    • Mechanical Engineering
Replies
4
Views
4K
Crankcase Supercharging Question
    • Mechanical Engineering
Replies
2
Views
2K
My idea for a diesel-electric hybrid
    • Mechanical Engineering
2
Replies
35
Views
3K
Increase RPM by decreasing stroke?
    • Mechanical Engineering
2
Replies
44
Views
43K
Automotive Ozone Enhanced Combustion of Water/Diesel Emulsion in CI Engines
    • Mechanical Engineering
Replies
6
Views
1K

Hot Threads

Recent Insights

Back
Top