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0-320 h.p. increase, help wanted

I’m confused. What aluminum?

How would increasing the oxygen level, up to that which is available at sea level, in the intake manifold at atmospheric pressure burn holes in anything? I’m sorry; I just don’t understand why that would be a problem.
 
Might be a good idea to monitor the EGT for all cylinders and add O2 only to drop-normalize EGT? From the AI earworm on my computer:

"As pressure altitude increases, exhaust gas temperature generally also increases, meaning the higher the altitude, the hotter the exhaust gases will be from an engine, primarily because of the decreasing air density at higher altitudes which results in less efficient combustion and more heat being expelled through the exhaust.
Key points about exhaust gas temperature and pressure altitude:
Less air density:
At higher altitudes, the air is thinner, meaning there are fewer oxygen molecules available for combustion, leading to less complete burning and higher exhaust gas temperatures.
Engine adjustments:
While engines can be adjusted to compensate for altitude changes, they often still experience increased exhaust gas temperatures at high altitudes.
Impact on performance:
High exhaust gas temperatures can indicate reduced engine efficiency and potential performance issues at high altitudes.
Important factors to consider:
Engine design:
Different engine types may react differently to altitude changes, impacting the rate of exhaust gas temperature increase.
Operating conditions:
Factors like throttle setting and air intake temperature can also influence exhaust gas temperature at various altitudes.
"Hot and High" operations:
Pilots need to be particularly aware of the potential for high exhaust gas temperatures when operating at high altitudes and hot ambient temperatures ("hot and high" conditions)."

Gary
 
If there was a direct way to measure % O2 in the intake it might help performance. The problem would be balancing weight (or mass) of fuel vs weight of the incoming air and added O2. That's so the fuel metering device (like a carb) could maintain via venturi vacuum from flow the best power ratio - see the chart below. Indirectly we can measure O2 outlet pressure or volume from the cylinder, and EGT/CHT/manifold pressure values from the engine. Hitting the max power point shown below might be a good experiment.

Gary

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Look at modern cars for the answer. Turbocharge. This year’s Corvette is a great example. A factory car producing 1068 hp with a 5.5 liter engine. Top speed 233 mph. You can go to your Chevy dealer and buy one. My big Sprinter van weighs 9000# and scoots around the country quite nicely with a 2.0 liter turbo diesel getting close to 20 mpg. Turbos are the technology little engines have been waiting for.
 
It would be great if turbocharged automobile engines were designed, tested, and proven to run continuously for thousands of hours at full power, but they're not.

Our problem is aviation engine manufacturers justifiably refuse to invest enough resources to bring modern materials, manufacturing techniques, and 21st century automotive technology to the GA market. Automobiles get the trickledown benefits from F1, Indy car, and NASCAR because it helps them sell 10s of millions of cars and trucks each year.

It simply isn't worth the investment to develop engines if the total market is for, at best, thousands of GA engines per year. FAA regulations and liability insurance costs don't help.

Heck, they still build and run PT-6s and Garretts with basically the same design as when they were first built in the late 50s and they cost about $1 million each. According to Wiki some 12 million car engines are produced each year. Lycoming has built only 350,000 piston aircraft engines since production began and only 65,000 P&W PT-6s.

It looks to me like battery powered electric engines are likely the only scalable and affordable option for the small GA market. And I still think adding a little extra O2 into the intake manifold wouldn't hurt.
 
There's more to optimizing air fuel ratios than I presently know, but it's available online as are new O2 sensors and panel gauges. The sensors don't like lead, so may not last long. However, the tech exists primarily for engine control unit input when variable fuel injection, timing, and a knock sensor are used to maintain either power or economy.

Most sensors in the road world designed for emissions are narrow band and reflect ratios +- 1 or 2 from 14.7:1 (in # of air/fuel) in the exhaust via sensed voltage. That's an optimum mixture for general operation. Higher is leaner (less fuel or more O2), less is richer (the opposite). Wide band sensors read over more of a range of A/F and voltage.

By leaning in flight we reduce fuel which leans the engine, generally first to a peak EGT/TIT or CHT value (see #64 chart), or even beyond for LOP ops. Then we can add some fuel to lower the EGT per the engine manufacturer if running rich of peak. We can also max indicated rpm for power, but at a slightly richer mixture than peak EGT (see the chart).

What the effect of added O2 would do I'll have to speculate out of ignorance. It would return the air fuel ratio to a leaner value (in voltage terms that's toward about 0.5V in a range of 0{lean} to 1{rich}). I assume the A/F value on the gauge would then read about 14.7 at that voltage (?). Per the chart a bit richer A/F can yield more power (about 150* rich of peak). In motorcycles that's about 12-13:1 A/F WFO that then resets to the 14.7:1 at cruise settings. Comments?

Gary
 
How about adding a wideband O2 sensor and gauge to a header or collective exhaust. Read air/fuel ratios and adjust O2 flow to desired result. What that would be is an experiment.

Gary
A local guy modded his 172 with such a sensor & gauge.
He told me that there was no "lean of peak" or "rich of peak",
but instead there was some absolute best ratio which you should always lean to.
I think he was working on an STC, but I never heard about him getting it.
 
A local guy modded his 172 with such a sensor & gauge.
He told me that there was no "lean of peak" or "rich of peak",
but instead there was some absolute best ratio which you should always lean to.
I think he was working on an STC, but I never heard about him getting it.
Yes there's a best A/F ratio for optimum fuel burn (that 14.7:1), and another for best power. Probably a good way to cook an engine if not paying attention to just another instrument.

Gary
 
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