Just Putting This out there. Engine build.

FRANK'S

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Joined
Sep 25, 2015
Messages
571
Location
ONTARIO CANADA
Aircraft
1975 Bensen B8-M A65 Continental
Total Flight Time
3
Just putting this out there for open discussion my head is working so much I don't sleep much at night.
I think of all types of stuff but mostly mechanic, racing, and Gyroplanes.

so this is something that Has been in my head for 5 years plus.
this is for a direct drive setup with a propellor in the 55" to 56" rage unless you advise me otherwise.

The attach pic you see is the original engine specs
90hp @ 4100 RPM
135 lbs Torque @ 2100 Rpm
2.5 liter 4 cylinder Cam in block engine.
I has selected this engine for racing application for it's low rpm high torque design.

But I could not leave it stock I put a great deal of time and cash investment in this engine
and it paid off this was a awesome race engine keeped me in top 5 every race I was the only 4 cylinder in top 5 all the rest
where V6. I rev this engine to 6500 RPM for 35 to 100 laps and it never ever ever gave me problems.
got 1st too but many 2nds 3rds and 4ths

now I tell you what I did to it.

.30 over Hyperbaric pistons. not strong like forged but next best thing.
Debur and gasket matching ports on cylinder head and .250" taken off head.
took off 1.5 ratio rockers and installed roller tip 1.72 to 1 on
crank is balance and counter weight filed in a way that can turn easily in oil splash " sharpened"
conrods are crower H-beam 305GM rods
this engine has 240psi or compression and torques like a monster V8
now if I would change it's aplication to a Gyro.


now on a Gyro I don't need 6500 RPM
I was thinking of 2300rpm to 2600 rpm High torque section for this engine.
For Fuel injection MS3 already have 80% of the kit.
or a 1 Barrel Carb from a 300 CI ford F-150 this is what I raced with.
on take off could I rev at 2900rpm if I got the right propeller?

with all the work I did to this engine I'm sure I raised its HP and Torque
but lets be realistic lets say....
100HP at 4000rpm
140 lbs or torque at 2200 rpm
I know I know this is not right on but it's a estimate.
this engine is about 200 lbs+ maybe a bit more in FI set up

Now lets Say on a Gyro would it fly well?

on a Air Command 1 place

or Air Command 2 place


how would it fly like a dog?
come on lets talk about this
I'm not worried about the engine
it won't break up it's a solid build
would lowering the compression
be a good idea?

Come on lets talk good or bad
well I don't want the a plane engine is a plane engine since I know
this is just talking for the sake of talking, I'm not a Mechanic enginire
but I have lots of tools



P.S. On the road with 5 speed trany this engine does 47 MPG US










[IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/www.theraptorpit.com\/Upload\/images\/race.jpg"}[/IMG2]
 

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Who originated the engine? What fuel? Supercharged?
Brian
 
As a former mechanic myself, I had all of these thoughts going through my head also. Being a "racing" engine, it's probably pushing it's hardware/bearings/heat higher than originally designed. This would make it have a shorter life. Aircraft engines are made with lower compression and larger bearings to get max life out of the parts. 90 hp is great power, 200 lbs of engine is not so great.
I fly an estimated 95 hp Subaru engine in a single place gyro that has an all up flying weight (with pilot) of around 820 lbs. I use a PSRU with a 2.58:1 gear reduction to slow the prop down from the 5400 max rpm of the engine to just under 2100 prm at the prop. My 68" prop should be turning around 2700 to get the max efficiency. I had to make it a 4 blade prop to get the thrust out of it. And went with a 25' rotor to get the lift.
To make a long story short, my single place Air Command flys great with a heavy 95 hp car engine. But I'm always scouting out landing options as I fly.
 
In my opinion to get 100 horsepower out of this engine you will need to rev it to 3,800rpm. 2,900RPM might get you 80 horsepower.

You are probably going to add another 30 pounds for a propeller speed reduction unit and 15 pounds for a radiator with coolant in it Frank.

In my opinion a 245 pound engine making 100 horsepower may not be the best choice for an aircraft.

The Lycoming IO-320 in The Predator weighs 255 pounds and makes 160 horsepower and cost $6,500.

In my experience lowering the compression generally lowers the torque.

Writing in very general terms peak torque falls off when it reaches the limit of the intake system and is less able to fill the cylinders.

Horsepower may continue to rise with rpm at a lower rate because the torque is falling off.

In my opinion for aircraft use; horsepower is what does the work.

All the best on your project Frank.
 
[ Smack Brian ] The Engine is a rare engine it's a 1986 to 1990 Ford Taurus 2.5HSC/HSO it was a engine that made 47 plus Miles per gallon and was making 400.000miles plus and still running.
The 2.3L HSC from the Ford Tempo was much more popular then the 2.5 liter ford Taurus.


AirCommandPilot not a real project just something that makes you go hummmm what if, Don't forget this is with a direct drive prop set up no reduction gear and engine has very big trust bearing it since I build this for racing applicartion with a stage 4 clutch I had to beef everything up for added pressure to the flywheel with clutch system harder to press on.


Vance Vance this is not a real project, it's just things that go in my head just wondering if it would fly weel to climb at 800fpm or there about and cruse at 60+ mph,
I'm building this project here with you guys on the forum and I want direct drive setup I know there are props that can turn 2900rpm some some 2600rpm and some lower
 
lets build this in a 1 place gyro to lower it's work load and give it a chance and lets compare it to a semi-modern subaru 2.2 liters non turbo would it fly similarly?



More Info on Engine but don't forget this is just base spec since I have lots of different parts in it.

tt6.jpg
 
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FRANK'S; [URL="https://www.rotaryforum.com/member/19952-aircommandpilot" said:
AirCommandPilot[/URL] not a real project just something that makes you go hummmm what if, Don't forget this is with a direct drive prop set up no reduction gear and engine has very big trust bearing it since I build this for racing applicartion with a stage 4 clutch I had to beef everything up for added pressure to the flywheel with clutch system harder to press on.

Vance Vance this is not a real project, it's just things that go in my head just wondering if it would fly weel to climb at 800fpm or there about and cruse at 60+ mph,
I'm building this project here with you guys on the forum and I want direct drive setup I know there are props that can turn 2900rpm some some 2600rpm and some lower[/B]

If you go to direct drive you are looking at having a heavy single place gyroplane (800 to 900 pounds gross weight) with 64 horsepower if you have direct drive.

In my opinion it will not climb at 800 feet per minute.

With a PSRU you effectively add 36 horsepower for 30 pounds. I would go with the PSRU.

Remember that to be structurally sound the frame to support such a heavy engine will need to be heavier. I feel weight is the enemy of flight.
 
Now Let do this Any flight simulator program that we could build this in different setup and see what it does?
This could be fun, Trust me I have the computer to run almost any program available today.
Thanks Guys I'm Having fun thanks for playing.
 
OK So I called my machinist and we talk about the engine he bored for me and I told him the times I did on 1/4 mile with it and he tell me with the times
I have it's sure I have over 140hp in the engine and I'm sure he is right he has been doing engine for over 50 years and know his stuff and it's why I only use him.

Now the thing is I don't know at what RPM this power comes on so would make it very hard to calculate gearing and propeller needed for this setup.

2550lbs car
14.1 1/4 mile times
92mph

Same car different engine

2550lbs
12.03secs My best time is 12.00secs but I don't have a video so it's like it never happened.
129.69mph
This I have a dyno run and know the HP
Dyno run gave me 325hp at the wheels

would you like the video of this run?
 
Less rpm makes less horsepower Frank. Going from 4,100 to 2,900 rpm reduces the power to 70% of what it was making at 4,100 rpm. 70% times 90 makes 64 horsepower.

Going from 6,500 rpm to 2,900 rpm reduces the power to 45% of what it was making at 6,500 rpm. 45% of 140 horsepower makes 63 horsepower.

That is why I wrote that a PSRU would be money and weight well spent so you can rev the engine higher and make more power.
 
Vance

This engine makes it's HP at 3800rpm
and makes it torque at 2200 rpm
so I would need a PSRU of 2.1 to 1 or there about
On the quarter mile run's I never saw 6500rpm only on oval dirt racing that I did on a 1/2 mile track.
so probably take off at 3200rpm to 4000rpm then cruze at 3000 rpm?
and since this high torque 140lbs++ would a 4 palm prop be the best?
What you think?
 
If an engine can breath more RPM will make more power.

It is my observation that the torque peak is generally where the engine begins to run out of air and not particularly interesting when it comes to an aircraft engine that will be running in a fairly narrow rpm range.

In my opinion a large two blade propeller would be the most efficient propeller Frank.

I have a three blade propeller on The Predator because I didn’t have enough room for a bigger two blade propeller.

More blades may be smoother and quieter than a two blade.
 
This thing can breath trust me I even have more duration on cam, bigger ration rockers, and over sized cam lifters and the HSC/HSO engine from Ford is like the Vortec from GM
but since it is a cam in block it makes torque at lower RPM range and why I build this engine for it's high torque at low RPM.

to Explain in a race we do rolling starts at very low speed so if you have a engine with great torque at low RPM on the Green flag after you hammer the the throttle it will pull more then other cars like type Hondas only the V6 guys where a challenge but a fun one..
and it did that very well on take off this engine made me move many possion and get out of the crowd/pack has we say.
 
so dry weight will be 621+pilot 871+fuel so 900lbs Ya Vance it will make for a very heavy 1 seater it would fly but would be unresponsive
and if engine quit would drop very fast and not give you lots of place to chose to land it.

and there are so many other choice of engine out there that would make a much better engine.

but still would be better then a 2 stroke rotax for reliability
 
Us ole rednecks always say;
There is no replacement for displacement, and its the torque that gets ya there but it requires the horsepower to keep ya there.
 
I'm a RedNeck but the fun types that get things done and build stuff.

But I found a replacement for displacement Turbos and superchargers.
make small displacement high HP and Torque.
 
I've been using a turbo for years with great results,turns my 5 bladed 68" prop pitched to 14 degrees @ 3,900 engine rpm/prop1,857,

cruises @75-80 mph. engine is a 2.5 Subaru.
 
eddie;n1131850 said:
I've been using a turbo for years with great results,turns my 5 bladed 68" prop pitched to 14 degrees @ 3,900 engine rpm/prop1,857,

cruises @75-80 mph. engine is a 2.5 Subaru.

what is the weight of your subaru 2.5l with turbo and all?

I can't turbo mine I'm close to 10 to 1 comp ratio
 
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