0-320 (dash) ???? Confused...Which one?

txaviator · #1 01-31-2007, 10:26 AM

I have printed out a Lycoming PDF which shows and explains all of the letter-designators after the intial 0-320 prefix. I also understand that certain model numbers were created when installed in certain production A/C, etc.

But as a real rookie in this engine stuff, how the heck is a guy to choose "the most ideal" model number? In a previous post, I asked for O/H advice, based on getting a used 0-320. However, the gentleman selling me the engine has dozens and dozens of 0-320's. Each one is sitting there on huge pallet racks, as far as the eye can see. Additionally, each one has a large cardboard description attached to it- showing TTSN, TTSMOH, log books, model number, etc. Gazing up at all these engines, I honestly get so confused looking at all the different model numbers that it seems to be a ****-shoot which model to choose? Keep in mind that despite whatever time may be listed, I still plan to O/H the engine before flight.

The nice thing is that I am a LONG way from actually "needing" and engine, but I'd like to go ahead and get one so I can work on it throughout the project, and as funds allow. Somewhere along the way, I also got this idea in my mind (from reading many posts on Lyc's) to stay away from the H2 models. I know they had some issues way back when. However, the gentleman with all the engines tells me he wouldn't let that bother him. He says the H2 models are REALLY easy to do inspection checks on, since many parts are easy to inspect based on configuration. He also has tons of them, and says they are "very tough".

So now I stand there and look at dozens of perfectly good candidate engines, but don't have the knowledge to point to one specific model and say "that's the one I really want". Can anyone help? Again, I know there are many-many versions of these Lyc's, and surely I can't be the only one who is perplexed by all the model numbers.

If it were you standing there, which one would you try to seek out, and which one would you not consider? By the way, the seller isn't biased one way or another, and isn't trying to steer me in any specific direction. He'll sell me whatever I want, and this is where it gets really confusing for me.

Thanks for any/all input. I hope I am not the only one out there with this dilemma (of not knowing the best choice when choosing from dozens of models).??? Imagine my confusion when staring at rack after rack of Lycomings.

Take care,

Ironflight · #2 01-31-2007, 10:43 AM

Hi Gary,

If I was shopping, I might do it something like this....

If I wanted a really simple installation, using Van's kits for FWF, I'd look to the engine models that they generally recommend - heck, try the models that van's sells. Look at those dash numbers, and see how those engines are configured (vertical vs. horizontal induction, C/S Prop setup vs. fixed pitch, etc.). That would give you a baseline engine model that you KNOW will give you a fairly easy installation. Now see if one of those is available. If not, then start looking at models that are close (for instance, many models differ only by the compression ratio, and that can be easily changed during overhaul).

Many years ago, I was upgrading my old Yankee to a big engine, and in order to help my shopping, I built this big "family tree" chart of the O-320 models on a large sheet of paper. It really helped to see the big picture...but alas, it is no longer around, lost in a move somewhere...

I agree that the sea of model numbers can be pretty intimidating - this is just one approach that might help you stay afloat.

Paul

Yukon · #3 01-31-2007, 10:44 AM

Don't buy an H model, dynafocal mounts are smoother, carburetted models are easier to install, cheaper, and easier to start, but don't run upside down.
Some take constant speed props, some don't. What else????

Mel · #4 01-31-2007, 12:57 PM

Also avoid the models like the ones used in the Grummans as the carb is located aft on the sump. Most exhaust systems aren't designed for these engines.

ddurakovich · #5 01-31-2007, 03:45 PM

Regardless of model numbers, be careful of the original installation.... Most Cessna engines don't have the pad on the accessory case for an engine driven fuel pump, a MUST HAVE for an RV

Narrow deck versus wide deck is more an indication of age than anything else, and is not even reflected in the model descriptions. I know some people have decided that continuing availability of parts may be an issue, but I doubt it will be for the next couple of decades or so!

You can usually modify anything on overhaul, including the accessory case, oil sump, induction system, etc. It just takes money! And sometimes, much more money than if you bought what you wanted in the first place, even though you got a great deal on the one you bought

mahlon_r · #6 01-31-2007, 05:17 PM

Common O-320 that will work in a RV seamlessly:
O-320-D3G, O-320-D2A, O-320-D2G with fuel pump, good 160hp, cs capable, but need to install gov drive, dynafocal. Good for FP as is.
O-320-E2A good 150 hp, cs capable but need gov drive, dynafocal, can be made 160hp with piston and piston pin change. Good for fp as is.
O-320-E2D with fuel pump or O-320-E3D, good Fp only, 150 hp, dynafocal, can be made 160HP with piston and piston pin change.
Check derivatives of these and note differences, for other pretty close fits.
Good Luck,
Mahlon
"The opinions and information provided in this and all of my posts are hopefully helpful to you. Please use the information provided responsibly and at your own risk."

az_gila · #7 01-31-2007, 06:25 PM

Quote:

Originally Posted by Mel

Also avoid the models like the ones used in the Grummans as the carb is located aft on the sump. Most exhaust systems aren't designed for these engines.

But if you do get one of these.... the O-320-E2G is the Grumman one - I have a sump and pipes I can sell you to convert it to a mid-mounted (as opposed to rear-mounted) carb. location....

The conversion is easy...

gil in Tucson ... still cleaning out the closet....

chesaning · #8 01-31-2007, 08:40 PM

Alex:
I would be interested in your sumb and pipes for the 0-320-E2G engine, I will be installing that engine in my RV-9. Please contact me at ab8ly@centurytel.net or call me at 810-955-3703

Fred Fagan
Flying Grumman AA1B, W/0320
Building RV-9

txaviator · #9 01-31-2007, 08:44 PM

Great replies from everyone; thank you. These small tidbits of information are being included in my "engine chart/tree" that Paul suggested

Your suggestions will make choosing an engine MUCH easier. Keep those great comments and ideas coming!

flyingf · #10 02-03-2007, 06:22 AM

I have a 0-320 b2b on a rv 6. The engine is run out and i am in the process of buying this aircraft. What would be the best thing to do with this engine. I am buying this aircraft for the speed. Would I be better off putting a 360 on the plane, overhaul the 320, or put an io-360 on it. It has a wood prop on it also. I am new to rv's so i don't know what it best in the long run . Will the extra speed with these engine be worth the extra gas expense.

Thanks