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Doing a bit of research

PostPosted: Sun Dec 23, 2007 1:52 am
by turbo_skylane
I've got a new pc..
Been messing with FSX, and since I like to try to keep my plane mods as close to life as I can, even though they may seem frankenstein-like or crazy..
Is there a company that produces turbochargers/ turbo kits for the aviation industry? I read about Rajay on google, but I cannot seem to find a website...
I'm not looking to actually buy turbo kits, just trying to make my franken-planes as close to life, if you were to actually take a cessna and hot rod it.
I appologize that its a bit offtopic...

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 9:30 am
by Brett_Henderson
That's an interesting topic. I'm an old car tweaker from way back, so I think along those lines too, when it comes to airplanes. A couple of years ago, I looked into buying a Piper Tomahawk. The problem with Tomahawks is their useful load (they have none) and that they're slow... and by modern standards; they burn too much fuel.

These are rough numbers from memory.. so don't hold me to them...

A stock, 110hp Tomahawk cruises at 95kias burning 6ghp. A new Liberty (similar size, 2-seat plane) cruises at 130kias burning the same 6gph.

Knowing that the 140hp engine from an old 172 would bolt right onto the Tomahawk, and didn't weigh much more.. I thought.. "Why not ?"

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 1:37 pm
by turbo_skylane
Well the plane I'm working on in FSX is the stock 172 Skyhawk II..
Why I turbocharge some of my planes is for shorter take off, higher climb rates, and overall just faster speed.
here's an exerpt of my aircraft file.

Engine\nTextron Lycoming IO-IO-720 400 bhp

[piston_engine]
power_scalar = 1.0                              //Piston power scalar
cylinder_displacement= 90.0                     //Cubic inches per cylinder
compression_ratio= 8.7                          //Compression ratio
number_of_cylinders=8                           //Number of cylinders
max_rated_rpm= 2650                             //Max rated RPM
max_rated_hp= 488                               //Max rated HP
fuel_metering_type= 0                           //0=Fuel Injected, 1=Gravity Carburetor, 2=Aerobatic Carburetor
cooling_type= 0                                 //0=Cooling type Air, 1=Cooling type Liquid
normalized_starter_torque= 0.3                  //Starter torque factor
turbocharged= 1                                 //Is it turbocharged? 0=FALSE, 1=TRUE
max_design_mp= 20                                //Max design manifold pressure, (inHg)
min_design_mp= 0                                //Min design manifold pressure, (inHg)

As it is right now, if you cruise at full throttle, it goes way past its max rpm. As it sits, it makes 9.8 PSI of boost. I'm not sure if its setup correctly.

I have the lycoming logo on the side of my plane, I wanted to add a turbo manufacturer on the tail or something, and possibly add a lil description to the engine section in the aircraft files..

What I'm going for, is sorta like what you can do with a car, you take your 350 outta your camaro and put in a 572 with a blower..
Sorta same thing, its kinda fantasy "if they would let you" and if "the plane would hold up" sorta thing.

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 4:10 pm
by Brett_Henderson
Yeah.. that kinda makes sense, but it's far from realistic. In the realm of fantasy, you might as well make hard-points and bolt a pair of jet engines under the wings... Or... "pretend" that with nitrous-oxide, an exotic fuel and outrageous turbo-charging (because that's what it would take to get nearly 500hp out of a four cylinder engine at less than 3000rpm

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 4:26 pm
by beaky
You don't see many gasoline-powered turbo'd 172s because it's not really an economical option, compared to just getting a plane with mnore "oomph".
But this is the latest approved mod for 172s... a (relatively economical) diesel that is  turbo-normalized:

http://www.centurion-engines.com/

It's also standard equipment in the DA42.

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 9:07 pm
by turbo_skylane
Yeah.. that kinda makes sense, but it's far from realistic. In the realm of fantasy, you might as well make hard-points and bolt a pair of jet engines under the wings... Or... "pretend" that with nitrous-oxide, an exotic fuel and outrageous turbo-charging (because that's what it would take to get nearly 500hp out of a four cylinder engine at less than 3000rpm  ::)  ) you can get magic performance out of a C172....

I wouldn't wanna share a ramp with a hand grenade airplane like that.. let alone climb into one...lol  :D


You'd have to rebuild that engine after every flight...

Edit:   ooops.. I see that you added 4 cylinders... that wouldn't fit under the cowling.. and you'd have to make it into a 2-seater, with the pilot straddling the empennage..


Heres the engine, from Lycoming's website.

Lycoming IO-720
720 Engine

Lycoming's eight-cylinder IO-720 series engines produce 400 horsepower at 2,650 RPM. These 720 cubic inch, fuel-injected engines have been the driving force of the high-performance Comanche "400" and of agricultural workhorses like the Brave and the Ipanema.

You do know the Germans did Nitrous Oxide in WWII.. Hmm.. I wonder how I could simulate that too..
How much PSI of boost should I run to keep it more "realistic"

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 9:52 pm
by Brett_Henderson
Heres the engine, from Lycoming's website.

Lycoming IO-720
720 Engine

Lycoming's eight-cylinder IO-720 series engines produce 400 horsepower at 2,650 RPM. These 720 cubic inch, fuel-injected engines have been the driving force of the high-performance Comanche "400" and of agricultural workhorses like the Brave and the Ipanema.

You do know the Germans did Nitrous Oxide in WWII.. Hmm.. I wonder how I could simulate that too..
How much PSI of boost should I run to keep it more "realistic"


Yes.. that's the 8 cylinder engine.. more than twice the size of the 4 cylinder, 180hp engine that's in a C172.

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 9:59 pm
by turbo_skylane
I'm trying to figure out how to put the emergency boost into the dash, since I just tweaked the cfg file to have methanol/water injection.
So I should put in a smaller engine? or put in the stock one. Still gunna turbo it.
Also, if it needed more fuel flow theres a boost pump switch in the dash, so that might do it?

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:04 pm
by Brett_Henderson
Oh heck..  just put a 28 cylinder, 3,800hp  P&W R-4360 in there   ::)


I give up...  :D

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:07 pm
by Brett_Henderson
That will require an external fuel tank.. so you might as well add solid-rocket boosters, too.  :P

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:25 pm
by turbo_skylane
:'( A bit extreme, no?. I didn't say I wanted a space shuttle  ;D
So I should "turbo normalize" and then configure the Methanol/Water injection for the OH CRAP WE NEED TO GO FASTER moments?
And put in a smaller, four cylinder motor.. what would be an exotic engine then? Gotta have something.. un-normal.

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:36 pm
by Brett_Henderson
Seriously.. honest.. trust me...  A turbo-normalized C172 would be most un-normal... a show stopper on the ramp... get gobs of ooh-ahhs..  There are no "gotta go faster" moments without altering the entire airframe.  The maneuvering speed for a C172 is barely 100knots.. and if you make a few steep turns at Vne.. the wings are coming off.

Airplanes are already high performance machines.. optimizing weight/power.. even little trainers. If you need to go faster.. you get a faster airplane...

I'm not trying to discourage your fun, but you're suggesting things that are outside of the realism window. Like I sarcastically suggested.. you can type the data for an R-4360 into the .cfg file.. and might as well if your just going for speed that isn't realistically possible..

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:48 pm
by turbo_skylane
okay then.I guess I'll put back in the original engine lol.
I was gonna use the Alcohol injection on the runway so it would accelerate faster.
What sparked this whole hot rod a plane sorta thing was me finding the Soloy modified Cessna 206 Caravans so it has a turboprop..
To turbo-normalize, you say keep the boost under 31inHg? so what I got it set to now would be good with a stock engine?
I still can't find some turbo manufacturers.. found Garrett/AiResearch and Rajay.. any others?

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:54 pm
by Brett_Henderson
Yes... just alter the cfg file for max manifold pressure of 30"

Re: Doing a bit of research

PostPosted: Sun Dec 23, 2007 10:57 pm
by Brett_Henderson
Oh.. and if you ever plan on taking a passenger up with you.. keep a 100lb sandbag handy to throw in the back seat, to compensate for the weight of the constant speed prop...  ;)