Turbo Sizing (hey Dust, over here!)

[LargePrime]

I dont know if I posted this but you all might find this interesting

 

http://www.turbofast.com.au/turbomap.html

 

I put in

RPM

2800 6 85 70

2400 6 85 70

2000 6 85 70

 

5.125"

4.375"

4 cly

-14 deg C (6.5 deg F at 15000ISA)

70% intercooler eff.

 

These were just rough guesses but not insane I think.

 

If you hit calc and move from map to map you will see the flow points move. Notice the difference when you change the number of cylinders to 2.

 

Any thoughts?

[Aaron]

Originally posted by LargePrime

The rule of thumb in racing was for every 10 degree cooler you got 2% more power. 1% without a turbo.

Does a Renesis really weigh 60lbs less? Where did it all come from? All the dimensions are the same.

Sorry just rechecked the facts- Mazda states it weights 30% less than the 13B-REW twin turbo, so the weight difference between the 13B NA and the Renesis is probably much less. At this stage it's hard to get real numbers (it's all marketing) but the Renesis shows lighter rotors and side housings, with a higher redline. TIme will tell what the overall weight savings is.

 

As for the rule of thumb- I am familiar with it, but I was basing my estimates on actual density calculations only. With colder charges you can advance timing more, getting more power than shown just by the density calcs.

[Rui]

The advertising for the Renesis also says that it is physically smaller (so that they could wedge it in further back to help the CG in the auto application). I suspect that this is mainly in the intake manfold and such accessory stuff, but either way it certainly bodes well for putting one of these suckers in a Cozy. It may actually mean that a mostly stock engine will fit directly into the cowl...

 

As I mentioned in a previous note, if it can do 250 HP at 8000 RPM then ~6000 it should do around 200 HP which puts it right where we want it. Then add a turbo for altitude compensation (I plan on flying over the Rockies many times in my plane) and you're laughing.

[John Slade]

Remember - that's 250hp with all the emissions stuff in place. Probably won't take much to get it up over 250 at 6k once that stuff is removed. Im expecting at least that from my 13B with mild porting and a turbo.

 

The stock intake will probably be too high for most cowls.

 

If anyone wants to give it a try, I believe our aussie freind, Leon, has feelers out for a few of the new engines at $10,000 au each.

You can find Leon on the flyrotary list.

[Richard Schubert]

Two points;

 

Regarding the suggestion from the beginning of this thread, if you mount the turbo's below the sump level, you will need scavenge pumps to return the oil.

There is a book "Turbochargers" by Hugh McGinniss(?)that covers much of the basic information, has a chapter on aviation turbocharging and sizing charts. It is available at my local Barnes and Nobel bookstore

[CBarber]

Leon from Oz stated that he has access to 2 Renisis' at $10,000. AUS (approx. $6500 US). This was a couple of weeks ago. If I had the immediate need I would follow through, but I don't even have the wings/canard yet for my Velocity SE project....it would probabley be best to get the whole plane first <g>. Do have my motor mount from Conversion Concepts and it is very nice. Fred stated he thought the Renisis has the same mounting positions as the late REW. Love the idea of stripping of the EPA stuff and seeing what this new fangled gadget can do......200mph cruise on my fixed gear????? Who knows? FWIW

 

All the best,

 

Chris

Houston

www.LoneStarVelocity.com

[dust]

OK so I talked to the salvage yard today, still looking for the logs, but, i thought, why not post to all of the messages and make it a "dusty" forum. Still excited about getting a TSIO360

[marbleturtle]

I figure the way people drive around here... its only a month or two before I can find one. But now I'm leaning toward two 9000 RPM motocycle engines running two 28" duct fans!

[dust]

I be an ignorant man, I thought i understood how a turboe worked, simple, just run a fan from the exhaust gases. Like blowing on a pinwheel. Well put a pinwheel in back of an exhaust and see ifin you can get 60 to 120 thousand rpm to drive a fan.

 

I don't think so.

 

HEAT diferential. the turboe heats the incoming air, it expands and drives the turboe, therefor you must retain heat to the turboe. Makes total sence and helps me allot in thinking on how to do this.

 

I would have tried to cool the damn thing off!

[Aaron]

On the EXHAUST side, yeah you're trying to retain heat,because as gasses cool their pressure drops, and the amount of work you can get drops as well.

 

On the intake side, you do everything to get it cool, despite the turbo's work of compression heating things up.

 

I don't know what youre saying about heat differential. The intake charge is heated because it is compressed by the compressor wheel.

 

The goal is to make sure theres a higher density gas flowing into the engine, thats all. If you assume PV=nRT, your goal is to decrease the V term. you can do that by decreasing the Temperature, increasing the pressure, or some combination of that.

 

So, like the old McDonalds sandwich, you keep the hot side hot, and the cold side cool, got it?

[dust]

the inside of the first cowling is layed up with the bulkhead in place and the cut line for seperation and i figured i had room for a 15.5 inch long naca duct.

 

measured the bottom duct for the first 15.5 inches and came up with 15.5 long 0 to 1.5 (well i rounded 1.25 to 1.5) deep and 6 inches wide. Not very big.

 

Thats good and bad. Not hardly any headroom lost and probably not much air flow.

 

So i decided to make two of them. Same size, but a left and a right. Could have made them bigger, because the cut line in the turtledeck is slanted, but decided to keep them minimal. I don't think that the loss in headroom will be noticable as they start out at 0 and i am using 3/8" foam over 1" foam for the support triangles with 3 layers of uni on each side two accross and one front to back.

 

We will see

 

Couldn't figure out where to put this post, probably should start one just for a turboe install, regardless of what it is installed on.

[Aaron]

My vote is for a new thread here though.

[dust]

OK just reviewed this post and will buy book "Turbochargers" by Hugh McGinniss

 

Also applied for n number today 110mt, thane will have to change his name to tango as mine is already mike, this is also in honor of marbleturtle, the current record holder for number of posts before buying the plans. he he he

 

with an n number i will rent the hanger, i am now # 1 on the list, signed up for it in 1997 or 1996, and will have a place to work on the engine

 

A friend needs the hanger and will pay fore it untill i need it, but in the mean time i will take delivery of the tsio360a and start the process of bringing it up to needs, one night a week, probably start this in january.

 

So tonight i found a supplier of exhaust flanges, reviewed this data and found a variety of info on the web.

 

Along with this, i have bought almost all tools known to mechanics mankind on ebay, just can't wait to find a reason to use that new 24" screwdriver

 

Now the work starts in earnest, fabbing the motor mount, the intake/exhaust/cooling/etc. etc.

 

The great thing is i have been thinking about this for a long time and to be honest, it doesn't look that forboding.

 

The motor mount has to be strong, but hey, there is no nosewheel attached

 

The engine has a turboe, so maybe picking one won't be all that bad, i mean if i can find it's ratings and dup them. and come up with the correct numbers to puut into the formulas, which yous guys seem to already have control of.

 

In the past i have found tech support at most places to be very helpful, if you have done your homework, which i am starting to do know, and you are looking for tweeking, not the entire design.

 

it's getting exciting and i can't wait to designate "ENGINE PLANE NIGHT" TO GO WITH PLANE DAY ON A WEEKLY BASIS, just won't have a chef there

 

hey guys, thanks for the info in this post, well except the rotory stuff, and hope you will stick around for the REAL info/ not just the BS thinking

 

enjoy the build

 

Mike

[mplafleur]

Hey, if it's Pontiac and you make it a Tuesday or Thursday night, I can stop by after Karate. It's only a mile away.

[dust]

Troy oakland, close enough, and you should see the tank, coming along nicely

 

enjoy the build

 

Mike

[mplafleur]

Well that's much closer to home, but I thought you said that first flight was going to be Pontiac.

[dust]

Wellllll, i'll do the engine work at troy, then probably take it to dave's for final install and cowling fab, etc. etc and then probably to pontiac for flights or maybe livingston county??????

 

enjoying the build

in a basement, in a garage, in a hanger

Mike

[mplafleur]

I'd suggest Pontiac. The runways are MUCH longer. Besides, the last time I saw a homebuilt take off from Troy-Oakland, it crashed.

[Aaron]

Dust are there any identifying marks on the Turbo? If so you might be able to find a rebuild kit for the turbo, assuming the housings aren't badly cracked.

 

If the housings are cracked, then the ID numbers will hopefully lead you to a compressor map, which will help a turbo manuf size one for your engine.

 

Congrats on getting this far!

 

blue skies,

Aaron

[dust]

OK, still just in the bs and minor learning stages of this but have a little more info. the engine is rated to 31.5 preasure, so i think that equates to almost no boost at sea level and a 3 to 1 boost at 25000 feet, i really want full cruise at 25,000. So, maybe that means i need 80% of 31.5 capacity at 25000 or do i still need 100 of 31.5 for 80% power at 25000???

 

I am looking around at components and am learning a little by reading specs and i saw a manual boost controller that you appear to set and forget.

 

So does it sound right, that i could set the boost at 31.5 and the preset controller could controll it and just keep it at the right preasure as i climb??

 

BTW, I ordered the book above that was suggested and another one that was recommended on amazon, so i am trying to learn, it is just a slowwwwww and exciting task that i can't leave alone

 

Interesting problem in aviation is the oposit of that in racing, we are concerned of overboosting on take off, while race cars are concerned with underboosting during use.

 

Boy i feel stupid asking these silly questions, but, i am learning and the learning curve should ramp up as soon as i read a few books.

 

enjoy the build

 

Mike

[Dave Clifford]

Hey, Whats wrong with the turbo or its specs that your engine came with?? Continental didn't slap any old turbo on there and hoped it would work. You have a proven marriage with your set up as is. You may need to rebuild or replace the unit, but I would leave it as is. Even thought I am going rotary, I plan to use the manufactures turbo unit or its replacement. No need to re-invent the wheel here. What say you???

[No4]

Dust,

The non turbo twin with a IO-360's I drive uses,

 

Take off full throttle (29"), Full rpm (2700 rpm), and mix rich.

Climb (25"), 2500 rpm, 13 gph

Cruise(24"), 2400 rpm, 11 gph

 

Our Seneca has a fixed waste gate, and once climb power has been set, and the beast gains altitude, you have to actually start CLOSING the throttle to maintain power. This is because of the increased pressure drop across the exhaust turbine, causing it to spool faster. I think it is rated at 200 bhp at sea level, and 220 bhp at 5,000 feet.

Ours never goes above 13,000 feet (no oxygen), but I presume there becomes a point when you start opening the throttle back up again, until ultimately you reach full throttle height.

 

A Manual boost controller that you set and forget? That's a bit of a contradiction isn't it? Is that an automatic wastegate? Surely the throttle lever is your manual boost controller. I'd prefer a fixed or manual wastegate as per factory. Be careful of automatic wastegates for use at sea level.

 

Remember that the turbo will be operating at altitude where at 25,000 feet it is 1/3 the air pressure at sea level. This means the turbine will spin faster and faster with a constant manifold pressure as you climb. Centrifugal compressors are only efficient between 75% and 99% of their design operating speeds. An incorrectly trimmed turbo would be as good as useless, and perhaps dangerous. If the compressor overspeeds, and the local air flow goes supersonic, you get a "lambda foot" shockwave forming in the housing, which basicaly ruins any compression available. (Same thing limits a big jet to travelling at Mach 0.8, except it's the flow over the wing).

Mass flow (horsepower) decides compressor wheel size, so again this may require a variation with altitude.(????)

I guess that an auto turbo might not be ideal for high altitude work.

 

Yes you are correct about turbo race cars. They are more interested in acceleration, so use small turbos which spool up quickly. For high power autos they use two small turbos in series rather than one large one. The engines are designed to require lots of boost at sea level. A single large turbo is more efficient than two, and for it to be boosting at altitude, it must be capable of overboost at sea level.

 

Looking forward to getting my rating in the Seneca beast, might have to grab some oxygen bottles...

[dust]

ohhhhhhhhhhh boy this experimental stuff, once you start on an area, it is hard to stop, so now i have completly lost my mind, i want it all on my continental.

 

electronic fuel injection with egt on each cylender for each cylender to be individually controlled for fuel, like gami but sensored and constantly corrected

 

computer controlled turbo

 

computer controlled electronic ignition

 

this is all mind bending stuff and I now have to buy more books and ask even more questions.

 

I have reviewed the controll system on the continental turbo and it is not surprising that it will allow overboosting, it is a $2600 valve with diaphrams and uses oil to sent to the wastegate to control boost

 

enjoy the build

 

Mike

[Jim Sower]

My reference on turbos is a guy known as "Turbo Tom" on the Subaru list. He had a hand in Greg Richter's turbo 13B and has been in the turbo business for 20 or 30 years. If/when I turbo anything at all, I aim to work with him extensively and do pretty much everything his way.

 

Contact him at turbotom@mindspring.com and tell him I sent you.

 

Hope this helps .... Jim S.