[jeffv7727]

Could anyone tell me how much performance increase a person would realize with 160 fuel injected verses 150 carbureted engine in a RV-9A?

 

[Kevin Horton]

Could anyone tell me how much performance increase a person would realize with 160 fuel injected verses 150 carbureted engine in a RV-9A?

There should be very little if any difference in power due to the choice of fuel injection vs carb. The big benefit of fuel injection is during cruise at less than 75% power when you can lean more aggressively and achieve lower fuel flows.

The increase from 150 hp to 160 hp would increase max speed and 75% cruise speed by about 2% or about 4 mph. The rate of climb should increase approximately 140 ft/mn if you have a constant speed prop, and perhaps 110 ft/mn if you have a fixed pitch prop (assuming 1750 lb weight, 75% prop efficiency in the climb, and only an 8 hp increase at the lower rpm of a fixed pitch prop).

 

[gmcjetpilot]

Two different topics

150 v 160 hp? Very little diff and the 150hp will be a little lighter. FI v Carb does not affect HP. You can have carb or FI on either 150 hp or 160 hp; however I think all 150 hp engines came with carbs from the factory, but you could put FI on a 150 hp engine or any engine that came with a carb for that matter.

FI v Carb: Much debated and many threads on it. I'd invite you to search the archives. Bottom line HP and FI have nothing to do with each other. Kevin is correct you can save fuel with FI in cruise. The debate is does it pay for it self. Constant speed props are more efficient as well but like FI cost more than fixed props. Fuel savings is not really the main reason to go with FI or constant speed prop. FI is a must for sustained inverted flight (along with an inverted oil system). Of course you can do acro with a Carb if you keep pos G's.

 

[N941WR]

... FI is a must for sustained inverted flight (along with an inverted oil system). Of course you can do acro with a Carb if you keep pos G's.

Geo -

You are a funny man! inverted flight in a -9 should be interesting.

Jeff -

The big difference between the 150 & 160 HP engines is the compression ratio. If given the choice, go with the 150 HP either injected or carb'ed because it will have no problem buring 87 oct. auto fuel. (Assuming no 'shine is mixed in.)

 

[gmcjetpilot]

Roger Roger, Clearance Clarance #2

Geo -

You are a funny man! inverted flight in a -9 should be interesting.

Jeff -

The big difference between the 150 & 160 HP engines is the compression ratio. If given the choice, go with the 150 HP either injected or carb'ed because it will have no problem buring 87 oct. auto fuel. (Assuming no 'shine is mixed in.)

Thanks RV9, my bad, no acro for the Nine-Ooo, got it, but generally if doing advanced acro FI is the way to go, Roger Roger. Does not apply to the RV9.

 

[osxuser]

How is the 160 any heavier than the 150..?

 

[Neal@F14]

150hp vs 160hp is just a matter of compression ratio. (7.0:1 vs 8.5:1) The 160hp 8.5:1 engine will run more efficiently, will burn less fuel to cruise at a given airspeed than a 150hp engine would in the same plane at the same airspeed and at the same absolute horsepower output level, and will probably run lower CHTs and EGTs too. The 8.5:1 compression ratio is a real sweet spot in this engine, but really wants 91 octane fuel minimum, which is still doable with premium unleaded autofuel if you desire to run on mogas. The 7.0:1 compression 150hp will let you run low octane "swill" for fuel.

Fuel injected will be more expensive to buy and overhaul when that time comes due and will give you problems hot-starting, but will be immune from carb icing and will run smoother when you lean the engine more aggressively.

If you can swing the price, go with a fuel injected 8.5:1 compression 160hp O-320. You can never have too much power in an engine, since you can always throttle back to make less power

 

[RV6_flyer]

How is the 160 any heavier than the 150..?

The pistons are .032" higher and the piston pins (steel) have a thicker wall. Not sure if the weight amounts to an entire pound or not.

The piston pins are for the EARLIER manufactured engines. Check with Malron to see if that is still the case with NEW 150 HP engines.

 

[gmcjetpilot]

More than compression on some

150hp vs 160hp is just a matter of compression ratio. (7.0:1 vs 8.5:1) The 160hp 8.5:1 engine will run more efficiently, will burn less fuel to cruise at a given airspeed than a 150hp engine would in the same plane at the same airspeed and at the same absolute horsepower output level, and will probably run lower CHTs and EGTs too. The 8.5:1 compression ratio is a real sweet spot in this engine, but really wants 91 octane fuel minimum, which is still doable with premium unleaded autofuel if you desire to run on mogas. The 7.0:1 compression 150hp will let you run low octane "swill" for fuel.

All very accurate and true but as RV6_flyer there can be many physical differences between a 150HP and 160HP engine, that's more than just compression. Some 150HP are basically lower compression 160HP engines but not all. Differences between 150 HP engines (especially older models) are things like cylinder choke. To save cost, Lyc made some 150 HP engines (not all) with smaller crank journals (I recall). These models are undesirable to upgrade to 160 hp down the road. Many early 150 HP engines tend to have Conical mounts, which is not as desirable as Dynafocal. So not all 150/160hp parts are the same across the board. I would not be surprised if some 150hp unique parts cost more than 160hp parts, just from volume. There are a lot of 150hp engine out there in Cessna's and Pipers.

What does it matter? Well if you keep the 150 HP engine at 150 HP, it does not matter. Performance wise you'll see little difference. I had a 150 HP Lyc O320 and constant speed prop on my RV4 and it was as fast or faster than almost all the 160 HP I flew with and even a few 180 HP RV's (it made them mad ). They would out climb but top speed? 10 HP is not a big deal.

It is true the 7:1 compression makes it more desirable to run lower octane MOgas (auto-MO-tive). I have always been sour on MOgas in RV's because of the hot tight cowl and vapor lock issues. Plus I did not see a huge saving with airport bought MOgas, MOgas availability at airports is marginal and hassle/danger of hauling own gas around. However with gas going to $5/gal I am less sour (and poorer). You can (some have) run Premium MOgas in 8.5:1 but you running closer to detonation. Lets face it Premium MOgas is not cheap either and now most are putting methanol/alcohol in fuels. You can always retard timing a little to make up for lower octane gas, but than your 160hp engine is back to 150hp.

Really if you are buying a NEW engine than get 160HP. They just don't make new 150HP engine, unless you special order it. If buying a used salvaged engine and you find a nice 150HP engine, use it. If you buy a run-out 150hp you can upgrade many or most of them to 160hp. I would not worry about performance OR fuel in your decision. If you are not happy with the 150HP in a few years you can easily sell it as a running deal. Than go buy a new 160hp engine. I would sell and buy than overhaul/upgrade a good running 150HP engine.

 

[Jconard]

The new 320's are made form the same casting as the 360's and there is very little weight savings.

But the older, often narrow deck engines, have listed weights which are 30lbs less. In addition, many of these engines are now available used and super duper cheap. They are coming off older airplanes like the twin commanche which are retiring at an increased rate. And, now that everyone wants the big HP engines, the 320's are flooding the used market.

So, there are opportunities to save money and weight. I am a tight budget builder and bought a first run 320, installed originally in 1968. The internals went back together for barely a polish and new bearings, and with a set of ECI-Lycon cylinders, new mags, new carb, new fuel pump, etc...it went together for less than $12K. I have the lightened prop hub, but I am running the WW 151 prop, which is lighter than most metal FP...so I doubt I will have a problem. The deals are out there.

Once flying, and depending on fuel, I may well put lower compression pistons back in and see how it goes. If I fly like I used to (3-hour legs or less), the HP difference would be negligable.

 

[JonJay]

Thanks RV9, my bad, no acro for the Nine-Ooo, got it, but generally if doing advanced acro FI is the way to go, Roger Roger. Does not apply to the RV9.

A little off topic, but dont forget about the Ellison. Adapts to any Carb engine and works in all attitudes. You dont need FI to do advanced Acro or my Bucker would have fallen out of the sky a long time ago
It is also a reasonable solution for the RV9 as those I have polled seem to be able to lean better than most carbs. Not sure why that would be, but....

 

[RScott]

Earl Lawrence is the technical guy at EAA who ran the tests to justify STC's for autogas. With all the turmoil in Oregon lately about the new law mandating ethanol, we have been learning a lot about the gas situation & where the experts see things going.

The upshot is that when I asked Earl yesterday about 150 vs. 160 hp for my -9A, he said to go with the 160. After break-in it can run on premium or 100LL, so autogas is still workable. If/when 100LL goes away or if/when all autogas has ethanol, there will still be fuel for the 160. Meanwhile, with the 150 you are more likely to have lead fouling and other lead related problems if you have to run 100LL.

Note that the US senate yesterday passed the new energy bill and in addition to calling for higher gas mileage for cars, it mandates a 7 fold increase in ethanol by 2022. The house still has to massage it & the pres. reportedly says he will sign it, so more ethanol is coming.

Richard Scott
RV-9A Fuselage

 

[penguin]

Could anyone tell me how much performance increase a person would realize with 160 fuel injected verses 150 carbureted engine in a RV-9A?

I did this on an RV-6A, although I kept the carb. Climb rate is much improved, on a hot Texas day and heavy I would be down to 5 or 600 fpm with the tired 150. With the 160 I'm hardly ever below 1000 fpm. Take off performance is slightly better (but I had to add 3" pitch to my Sensenich), and cruise is better by 5 or 10 mph, especially up high, but some of that might be due to the E-mag. I don't recall any fuel consumption difference, but I tend to fly WOT most of the time, so am probably going faster at the same consumption. Definitely does not use any more fuel. I would go for 160hp every time.

If you fit FI you may need a larger air scoop on the bottom of the cowl.

Pete

 

[gmcjetpilot]

Farm Lobby wins

Note that the US senate yesterday passed the new energy bill and in addition to calling for higher gas mileage for cars, it mandates a 7 fold increase in ethanol by 2022. The house still has to massage it & the pres. reportedly says he will sign it, so more ethanol is coming. Richard Scott RV-9A Fuselage

There's that Farm Lobby at work baby! Wish I was a corn farmer. Corn ethanol is totally lame, containing only 1.3 times the energy required to create it. U.S. corn-derived ethanol costs 30% more because the corn starch must first be converted to sugar before being distilled into alcohol. U.S. does not import Brazilian ethanol because of strict U.S. trade barriers (tariffs) corresponding to a levy of a 54-cent per gallon. Why not grow sugar cane or switchgrass? Even experts agree, ethanol only has the potential to displace at most, 10% to 20% of the world's oil demand. I know truck, sport car and SUV lovers will hate this (I love my V6) but just getting gas millage up to 40-50 mpg on all vehicles would save more fuel than ethanol. We have the technology now, but it means small cars with small engines. One thing for sure, free market needs to take over and farm subsidies need to end.

Rhetorical question (don't answer because its political, just food or ethanol for thought)? Why do the first Presidential caucus states like Iowa and New Hampshire have disproportional say in who will get the major parties nomination? After the first two or three primaries its all over, and the rest of the country has to choose who they and Oprah decided on? Does not seem fair. Why Iowa? Why bother having party conventions if they just pick who a few primary voters from a few states decide on?

 

[Norman CYYJ]

Saying 10 to 20% of the gas will be replaced with ethanol, it is not achievable. There is not enough farm land in the world to grow that much corn or what ever and still grow food for us to eat. Besides using alcohol mixed with gasoline per pound will produce less horsepower therefore bigger engines and more fuel burnt. But it does keep the tree huggers happy and the farm subsidies up. Net loss all around in many ways.

 

[gmcjetpilot]

Lots of land

Saying 10 to 20% of the gas will be replaced with ethanol, it is not achievable. There is not enough farm land in the world to grow that much corn or what ever and still grow food for us to eat. Besides using alcohol mixed with gasoline per pound will produce less horsepower therefore bigger engines and more fuel burnt. But it does keep the tree huggers happy and the farm subsidies up. Net loss all around in many ways.

Good point that is another layer of the issue is land use. You are right the energy density is pretty low. Also ethanol does not work for starting at cold temps (turns into gel). So you need special fuel heaters, another wrinkle. I think its part of the big solution, but not a panacea. With the Gov and special interest involved this solution is in doubt and may be forced down our throats.

 

[rv9aviator]

You can get 40 MPG and still stay in a normal size vehicle. I have a Toyota Camry Hybrid that get gets an average of 40 MPG per tank. It doesn't care if it's in town or on the highway. I have gotten as high as 46 MPG on a 300 mile trip with the conditions being in my favor. I have 16,000 miles on the car now and absolutely love it. I've got to save money somewhere to buy Avgas for the -9.

 

[Bryan Wood]

You can get 40 MPG and still stay in a normal size vehicle. I have a Toyota Camry Hybrid that get gets an average of 40 MPG per tank. It doesn't care if it's in town or on the highway. I have gotten as high as 46 MPG on a 300 mile trip with the conditions being in my favor. I have 16,000 miles on the car now and absolutely love it. I've got to save money somewhere to buy Avgas for the -9.

There are times when I'll be driving up hills on the freeway and cars start to slow down for whatever reason. Lack of power, sleeping drivers, ??? So now to hold my speed with the cruise on there might be some lane changing to go around cars as my supercharged commuter holds 75mph or so. Recently under these conditions I've noticed a new trend that is somewhat impressive and surprising. Passing me with ease are those hybrid Prius's as if power isn't dropping off at all for them. This option just might be in my future as the daily driver gets older.

 

[Norman CYYJ]

When the batteries get tired in those hybrid cars you're looking at around eight grand to replace them. They tell me they are good for about four years. That's a lot of gas you can buy for that much money.

 

[N941WR]

I've got to save money somewhere to buy Avgas for the -9.

It turns out the net pollution from a Hybrid is much HIGHER than a standard auto fuel powered vehicle.

Did you ever wonder why the batteries are made in China? The answer is because the pollution created to produce them. Even then, how are you going to dispose of those batteries when they need replacing? Just another HAZMAT issue to deal with.

Sorry, but from what I have read, Hybrids are just not the answer. I wish they were but they aren't.

Also the price premium you pay for the Hybrid can purchase more fuel than you would use driving an equivalent car (I'm talking Honda Civic Hybrid vs. Honda Civic fuel engine.)
Civic Hybrid $22,600 - Civic LX $16,960 = $5,640
Estimating 15,000 miles per year, fuel cost of $3/gal
Average MPG City/Highway for each car is:
Hybrid: 40/45 MPG
LX: 26/34 MPG

Figuring 50% city/highway yields the following fuel consumption cost based on $3/Gallon:
Hybrid: 354 Gallons @ $3/gallon = $1,06250
LX: 509 Gallons @ $3/Gallon = $1,527.15

For a yearly difference of $464.65

It turns out the payback for purchasing a Hybrid is 12.14 years. ($5,640/$464.65)

I'm thinking you would be better off buying the cheaper car and purchasing more fuel each year.

 

[cnpeters]

And, Bill, I would add the annual depreciation value of the batteries based on expected longevity, replacement and disposal costs. It would tip the scale even further towards the non-hybrid.
I know a hybrid Civic owner - she measured gas consumption highway vs city in the real world (via tank refill against mileage). Interestingly, highway mileage was a bit lower than advertised, closer to 38mpg if i recall, driving 70mph avg. She said the car was mostly running off the rather anemic engine at that speed - wind resistance was too high for sustained battery power.
I also know a Toyota Highlander Hybrid owner - sadly the only way to get that model when he did was fully loaded and quite heavy, with a rather robust engine. He sheepishly admitted his mileage figures were not good, and substantially below what Toyota publishes (I know there is a Congressional manadate to start publishing these figures with real world conditions in the near future).
Regarding ethanol, I live in the heart of it and know farmers and folks in the ethanol production industry. The latter have admitted the nearly 1:1 net energy balance with production (it takes about 1 unit of energy, mostly in fossil fuels, to produce 1 unit of ethanol energy). Oil can be 30:1 (30 units of energy per 1 for extraction, refining, shipping) from Saudi in the old days to much lower for us importers up to the bad 0.7 for the Canadian Tar Sands extractions (I have some neat inside skinny on that one too from a large equipment exec - nice smelly money trail there despite the crappy return). Here is a .pdf link looking at other ratios (like 15:1 for nuclear) - http://www.hydroquebec.com/sustainable-development/environnement/pdf/rendement_investissement.pdf
Here in Illinois, companies big and small are tripping over each other to gobble up the governmental subsidies and install distilling plants, each of which can consume as much water as a small town. And, as someone pointed out, all figures I have seen show we do not have the land to support much of a dent in our energy needs.
All of this is just following the money trail, making a minority rich, and sadly will cost taxpayers billions and lead us astray from more meaningful endeavors. I fear there will be a big 'spanking' coming to this country in the near future.