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RV-9A: 7A finishing kit, Superior Engine, Sensen 85" prop, will it all fit and work?

MrNomad

MrNomad

Well Known Member
RV-9A: 7A finishing kit, Superior Engine, Sensen 85" prop, will it all fit and work?

I have an RV9A and need to order the finishing kit. SUPERIOR sells an O-360 for lots less than Van's 320. With the 7.2 compression pistons, the Superior O-360 will generate 168hp. That's only 8 hp more than the 320 but allows me to run pure auto gas.

However, because the O-360 uses a slightly larger carb, I need to order the 7A finishing kit. I assume that will fit ok?

Now, onto props. The Sensenich fixed prop is a good value but Van's prop for the 360 engine expects 180hp. I only have 168hp. I assume if the performance is not as good as I'd like, we simply remove the prop and have it flattened a little.

The intended use for the airplane is cruising and my wife is skinny so takeoff should not be an issue.

Van's tech support was not happy with the 360 Superior engine choice.

I welcome anyone's experience on this issue. With a 10 week lead time, I wanna place the order.
 
Doesn't the O-360 weigh more? Will it burn more gas?

Have you looked at the Aerosport O-320? $20,100 FP, $20,400 constant speed. I have talked with them at Arlington and Oshkosh & they never tried to "sell" me on anything. Unlike the Superior folks who seemed to want to sell me an O-360 for my -9A not because it would be in my best interest but
because the didn't have an O-320.

Just my impressions.
 
Superior sells an O-320 so that's not the issue

RScott said:
Doesn't the O-360 weigh more? Will it burn more gas?

Have you looked at the Aerosport O-320? $20,100 FP, $20,400 constant speed. I have talked with them at Arlington and Oshkosh & they never tried to "sell" me on anything. Unlike the Superior folks who seemed to want to sell me an O-360 for my -9A not because it would be in my best interest but
because the didn't have an O-320.

Just my impressions.
Click to expand...

Thanks for the reply but Superior sells an O-320 so that's not the issue. Considering that the choices for using cheap(er) auto gas are a 150hp O-320 and a 168hp O-360, and both engines sell for the same price, makes it hard to resist the extra 18hp.
 
Since the fuse of the 7a and 9a are dimensionally the same, Vans will simply send you the cowl and fw forward kit for the RV7/360 combo. It will fit fine. I have a 9a with the 0360 installed. You will also hear of the horrible weight problem you are going to have with the 360 but the certificated wt difference between the 0360 and 0320 models that Vans sells is less than 10 lbs (I believe it was 6). If I remember correctly the dimensional differences are that the 360 is 1/2 wider on each side (longer stroke) and with the 4-5 carb it is 3/4 inch deeper--hence the deeper scoop on the 360 cowl.

Think about a Catto composite fp prop--you can go with either a 2 blade or a 3 blade for about the same price as the Sens. Craig Catto can cut the prop to the power output of your 168hp 360. I have a 3 blade Catto (weighs all of 17 lbs vs 42 for the Sens) and it is so smoooooooth!!! I can't comment on performance comparisons with the Sens since I have only flown with the Catto.

If you do decide to go with the Sens it is a very low maintenance prop and provides excellent performance on the RV line. Either way you win.

Cheers,

db
 
Just a note on autogas

I went with the Superior XP-360 with standard 8.5:1 pistons (180 HP) because it can use 91 octane or better autogas. I figured if it ever came down to it or AvGas became obsolete, I could at least still fly. Then they (EPA) managed to lobby and change the rules. At least in the Dallas area, if not all of Texas, they required the gas companies to replace MTBE with ETHANOL!!! This is for ALL car gas.

There went the option of using autogas, at least for me. Just thought you might want to check out your state for their stance on Ethanol in autogas.
 
hecilopter said:
I went with the Superior XP-360 with standard 8.5:1 pistons (180 HP) because it can use 91 octane or better autogas. I figured if it ever came down to it or AvGas became obsolete, I could at least still fly. Then they (EPA) managed to lobby and change the rules. At least in the Dallas area, if not all of Texas, they required the gas companies to replace MTBE with ETHANOL!!! This is for ALL car gas.

There went the option of using autogas, at least for me. Just thought you might want to check out your state for their stance on Ethanol in autogas.
Click to expand...
This is not intended to be a highjack of this thread or to cause any major arguments for or against ethanol but why is ethanol a deal killer for use in this engine? What is so bad about this fuel that would cause so much discourse? Call me naive or even ignorant but I fail to see why any of the "problems" that result from using ethanol can't be remedied with a few minimal alterations to some of the components of any engine, including aviation Lycosaurse's. Especially when we are looking at only a 10% solution of ethanol.
 
RV9A, RV7A cowl, Sens prop

Thanks to all who responded to this thread. Yes, Vans was not terribly happy that I planned to exceed the 160hp limit with a Superior O-360. Yes, Vans sold me the 7A cowl.

Yes, the 360 weighs 6 lbs more than the 320 which means my diet will get stricter.

Ed from Sensenich was great too, he said, "Order an 83" prop from Vans instead of the 85" prop and the 168 will work fine."

Barb (Vans) wrote it up, took what remains of my piggy bank and away we go.

Now, if I can only get 27 hours into each day and get the wife to stop asking me to do useless stuff around the house, we'll be in the air sooner.

Concerning ethanol, my partner on our Cessna claims that rebuilding kits for carbs cannot handle the ethanol. In addition, many of the hoses would have to be changed but if Edelbrock can create rebuilding kits for auto carbs to handle ethanol, there is no reason for some enterprising people to do the same for MA-4-5 carbs.
 
OK, I yield on the weight question--10 lbs can be offset by using a wood or composite prop.

But Superior's web site makes no mention that I can find of an O-320, nor does Avweb in their discussion of what Superior said at SNF. ECI does have an O-320. If Superior does make an O-320, I would like to know about it.
 
hecilopter said:
Even ignoring the fact that ethanol destroys the rubber seals we use in airplanes, it absorbs WATER. Not a good thing for airplanes!

http://www.sportpilot.org/magazine/feature/2006%20-%2006%20June%20-%20Power%20On.pdf
Click to expand...
Ok, as I mentioned previously, I did not intend to highjack this link but I feel compelled to discuss the ethanol comment(s). Rusty I appreciate your concerns about using a fuel you are not familiar with but again my comments are based on the fact that there are no inherent operational issues with running an internal combustion (IC) engine on alcohol. Alcohol will burn hot and clean and provide plenty of power as needed. If not, I don't think we would be watching Top Fuel (read as pure alcohol) dragsters on the 1/4 mile track.

Issues with particular compenents of an IC engine are the sticky point for using alcohol as a fuel. Alcohol can be corrosive so measures need to be taken to guard against corrosion. There is the added problem of increased risk of vapor lock. However, the first link you reference discusses the practice of using vapor/pressurized fuel return lines that return vapor back to the fuel tank as a method for resolving this issue. Regarding your comments about water absorbed by ethanol, I would question why you see this as a problem when the author of that same article you eluded to in support of your concerns mentions that ethanol's ability to absorb water is an "Advantage" of Ethanol.

Quote by: Phillip Lockwood, et.al.
Because alcohol absorbs water, gasoline with added alcohol should help keep fuel systems free of water, so water should not be present when sumping the tanks and/or gascolator on an aircraft filled with E10 or any form of gasohol.
Click to expand...
The fears of using another fuel or combination of fuel mixtures causing serious damage or performance problems for aviation engines can be addressed by adjusting the materials, methods, means of the various components and operational practices used in an IC engine. The Ethanol mixture does not adversly affect the power capability of the fuel in an IC engine (I am referring here to the 10% solution of Ethanol mixture. Clearly there could be an issue with range if using a higher % solution due to the lower BTU of Ethanol over gasoline.). Nor would it adversly affect the safety of an airplane flying with alcohol as a fuel once the affected components are appropriately scrutinized and the necessary changes to those components addressed.
 
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