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PTAirco

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From recent experience around here, they also come down rather fast when the fan stops.
 

Vector

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Anyone know what the cost and weight on this setup is? I didn't read the article. Realistically, what is an expected TBO?
 

rv6ejguy

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Brand new Aerosport engine. Has about 100 hours on it including racing at Reno last year. If you treat it nicely and run it below 35 inches, would probably go 1500 hours.

I think the base engine was around 420 pounds. I'd guess the supercharger, brackets and pulleys weigh around 40 more.
 

TFF

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Is it legal to have a RC turbine engine supply energy to a turbocharger. No exhaust restrictions and no parasitic hp loss. Has the NO2 Been tested under full boost? That's a fuel curve for the brave.
 

Vector

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Brand new Aerosport engine. Has about 100 hours on it including racing at Reno last year. If you treat it nicely and run it below 35 inches, would probably go 1500 hours.

I think the base engine was around 420 pounds. I'd guess the supercharger, brackets and pulleys weigh around 40 more.
At the end of the day, what is the power to weight ratio? Seems similar to the late Jack Morrison's setup. Maybe not with the nitrous.
 

rv6ejguy

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Is it legal to have a RC turbine engine supply energy to a turbocharger. No exhaust restrictions and no parasitic hp loss. Has the NO2 Been tested under full boost? That's a fuel curve for the brave.
The input hp required to turn this compressor for 40 inches MAP at 8000 feet DA is probably about 30-35. I doubt if the RC turbine is practical to do that. You'd simple turbocharge it. You don't worry about exhaust restriction on turbos since they have the hp capability of splitting a 540 wide open. The mission here was to make around 400 hp given the airframe Vne restriction and drag without changing the lower cowling shape which would have been required. That was accomplished and it worked well in the end.

The nitrous proved unnecessary.

The power to weight ratio is probably around 1.25 lbs./hp as installed.
 

TFF

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You are being too serious. Anyway the NO2 question I hope was figured out just in case; seen too many backfires take car engines out of the chassis to be guessing on a airplane.
 

narfi

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I think that's the same plane (model not physical) Paul Lamar is using for his time to climb project?
Claimed 650hp rotary @ <200lbs. They are still in early stages of test flights I think. Their goal isn't speed though and aren't even using a scowling which I am sure would need to be modified to fit the radiators.....
 

Toobuilder

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The nitrous explosions in drag racing is sometimes the result of trying to hide a cheater system or going BIG on the bottle... A well scienced out shot of the bottle is pretty well understood and safe. So much so that GM even considered it as an option in the mid 80's. Obviously, the bigger the shot, the bigger the risk, but 125 HP is pretty tame these days.
 

rv6ejguy

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I think that's the same plane (model not physical) Paul Lamar is using for his time to climb project?
Claimed 650hp rotary @ <200lbs. They are still in early stages of test flights I think. Their goal isn't speed though and aren't even using a scowling which I am sure would need to be modified to fit the radiators.....
They'd need a cowling for speed records for sure...
 

Aesquire

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https://www.youtube.com/watch?v=AScojLj139A&index=6&list=PLGvTvFzdMg_O2T3UdUEt5dIHutSOu7srE

Engine Masters. How much Nitrous can a stock engine take?

They test a used stock V8 engine and increase the power until it fails.... exactly as they predict.

A proper NOS ( brand name ) kit that adds fuel in proper proportion is a reasonably cheap way to get VERY short bursts of extra power, while having an engine that runs normally on the highway. If you keep the air/fuel ratio happy, an extra 150 hp out of a 350+ hp engine is reasonable & safe. ( Assuming the rest of the drive train can take it ) The problem with cars is usually running a poor air fuel ratio, and/or the sudden increase in heat. Very short bursts of extra power. 5 seconds, 6 seconds.... You can go more if you have done internal modifications to deal with the sudden increase in heat ( ring gap large enough to make your car a smoker at idle, Forged pistons, etc. ) I don't know anyone who uses Nitrous on the street for other than a quick squirt. 5 minutes? Asking for a melt down.

In aircraft applications the biggest issue is fuel/air ratio. Lean it out and you melt pistons like a cutting torch. Too rich and things break in weird ways.

A lead tolerant air/fuel sensor & gauge is a good engine management tool in any case. For boosted applications, A must. CHT's tell you what you've done after the fact, and for most people, you have to figure the trend out yourself.
 

Kyle Boatright

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I think that's the same plane (model not physical) Paul Lamar is using for his time to climb project?
Claimed 650hp rotary @ <200lbs. They are still in early stages of test flights I think. Their goal isn't speed though and aren't even using a scowling which I am sure would need to be modified to fit the radiators.....
Why would you do time to climb in the clipped wing version of anything short of an F-104? Long wings generally give a better climb rate...
 
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Kevin N

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I vaporized the bottom end on a Ford 302 playing too rough with NOS. I had timing problems that caused my grief. It was fun nonetheless. Looking at that supercharger I wonder how much they give up to run it compared to a turbo. Everything is a compromise. What kind of gas are they running when they are leaning on it? Av gas or VP or ?? Interesting for sure.
 
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