O-360 types

gsimatos · Post by **gsimatos** » Sat Sep 29, 2007 3:03 pm

I am getting to a point where I need to make a decision on an engine. I am going to go with a 360 but I don'k know the differences in the types. For example the "A" vs "B" and I think there is even an "M" designation. Can anyone help me get my brain around all the various "flavors" of engines out there? I am not sure about injection vs carbed but would like to go with the CS prop. I am sure many of you have been down this road and I would be interested how you decided on a particular engine model. Thanks Gary

captain_john · Post by **captain_john** » Sun Sep 30, 2007 7:31 am

Gary, the engine designations are very confusing. They say Lycoming has yet to make 2 engines exactly identical! When you see all the possible combinations, it really makes unique engine configurations extremely likely.

As there is only one "O"-360 option, I am guessing that you are also asking about the "IO's" as well.

The way I classify engine choices for the -7 in my mind's eye is like this:

O-360-A1A 180 hp (carbed)
IO-330-M1B 180 hp (injected)
IO-360-A1B6 200 hp (injected)

Essentially, the differences are:

Pros vs. Cons
Least expensive ~ Low power and crude technology

Medium choice ~ Injected but doesn't have the smoothness of the A1B6

Smooth and counterbalanced (can use any prop without restrictions) ~ Very costly

My choice is the IO-390. It is counter balanced like the A1B6, so it is smooth. That is my reason for going with it. I want a counterbalanced engine, bottom line. The 390 actually costs less than the counterbalanced 360 by a good margin. The added benefit is more power. For me, it is a win/win.

Which one are you leaning towards?

CJ

JohnR · Post by **JohnR** » Sun Sep 30, 2007 9:36 pm

Gary, CJ explained it pretty well above. One thing he did not mention is, if I remember correctly, that the IO-390 uses the IO-360 M1B kit from Van's as far as the finish kit goes. At least that is what my notes say from talking with Allen Barrett about the 390. I have the finish kit in hand and am planning on the IO-360 M1B but believe I still have the option of using a 390 if I wanted to change my mind. Just another data point for you.

gsimatos · Post by **gsimatos** » Mon Oct 01, 2007 12:46 pm

Thanks you guys. I am thinking about the IO 360 M1B ideally, if I win the lottery. I would like the CS prop also have to see what the budget can tolerate. I would like to get the firewall forward kit/engine mount and I think the mounts are different for each engine, is that right?? Narrowing the engines down to 3 "types" is a big help however. Thanks G

captain_john · Post by **captain_john** » Mon Oct 01, 2007 8:57 pm

John, actually...

The finish kit you want for the 390 is the A1B6. It is wider according to Van and Mattituck.

...at least that is what my understanding is.

Both the A1B6 and the 390 are angle valve and horizontally inducted.

Dunno...

CJ

Mahlon · Post by **Mahlon** » Wed Oct 03, 2007 6:07 am

try:
http://www.lycoming.textron.com/support ... SSP204.pdf
for engine model help, it might help.
And yes you want the IO-360-A1B6 FWF kit with a different prop governor cable setup for the governor mounting on the left front of the crankcase on the a 390 rather then on the back of the engine on the A1B6.
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."

captain_john · Post by **captain_john** » Fri Oct 05, 2007 2:42 am

Mahlon, glad to see that you are still checking in here!

Say, I was wondering...

With all the rising gas prices, can the 390 use MoGas? We have it here at PYM and I was curious.

As I recall, the stock 390 has low (8.9:1) compression so I am guessing it is okay.

I would like Airflow Performance Fuel Injection also, if it makes a difference.

Thanks,

CJ

Mahlon · Post by **Mahlon** » Fri Oct 05, 2007 7:03 am

Compression ratio on the TMXIO-390 is 8.9:1. We don't endorse the use of 91 octane MoGas on TMX engines with compression ratios above 8.5:1.
The fuel injection systems used on the TMX series of engine are compatible with MoGas.
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."

RV7Factory · Post by **RV7Factory** » Fri Oct 05, 2007 4:36 pm

Gary and crew. I don't know if it helps, but I have some "engine basics" covered on my engine page. I put it together to document my research -- There is a lot of opinion expressed, and please double-check the facts, but you might find something useful.

captain_john · Post by **captain_john** » Sat Oct 06, 2007 7:12 am

I see, 8.9:1 really isn't that low.

Another question for ya...

Reports are coming back that the 390 runs hot in the oil department. Most guys are installing large coolers like the SW 10599R.

Now for the question. (I think that I already know the answer.) How do you manage oil temperature effectively? Will the vernatherm (I think I spelled it right, the thing that controls oil temp on the engine) maintain a steady level of oil temperature being delivered to the engine or should I plan on installing one of those oil cooler shutters that Van sells? Would increasing the oil capacity be advantageous?

Brad, I will poke around your site too see what you have collected.

CJ

gsimatos · Post by **gsimatos** » Sat Oct 06, 2007 8:35 pm

Thanks you guys. Brad I checked out your engine page which was interesting and helpful. It really is a complex topic but also interesting. As you say I will keep talking/reading and try to come up with an engine choice that is correct for my mission type. Since I have ya on the phone regarding mag/ignition choices don't some folks use a regular mag plus an electronic ignition set up? This is a little confusing since the regular mag spark doesn't advance while the electronic ignition does. Does this work? Thanks and Happy Thanks giving Gary

captain_john · Post by **captain_john** » Sun Oct 07, 2007 5:56 am

Gary,

I am DEFINITELY going electronic. Initially when I first thought about ignition, I expected to have 2 electronic ignitions. Now I am planning to have 1 EI and one magneto.

As you know, when you have EI, the engine runs cleaner and the spark advances much more accurately. From what I have been told, you can accomplish this with just one EI and a mag in the other hole.

The EI will fire in advanced time and the mag will flash later. This will give you the benefits of having the EI (clean burn and advanced timing) with the reliability of a traditional magneto.

There are many EI vendors out there. I like the P-Mag by www.emagair.com and the one from Jeff Rose at http://www.electroair.net/.

As you said, the mag spark doesn't advance with the EI, but you really don't need it to do so in order to get the benefit of having EI.

My 2 centavos

CJ

Mahlon · Post by **Mahlon** » Mon Oct 08, 2007 8:45 am

The vernatherm will try to maintain 185F oil temp as long as the cooler has enough cooling capacity for the heat being generated. The reason most go to the bigger cooler, is that the oil cooling capacity of the smaller ones, is marginal for the amount of heat the engine can make during high ambient temperature months. Once the ambient’s are below 80F, the smaller coolers seem to work OK.
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."

captain_john · Post by **captain_john** » Mon Oct 08, 2007 9:36 am

Gotcha!

What is optimal oil temps anyways? I understand that the objective is to have enough heat to evaporate any water content in the oil. Is it safe to say that 185 degrees will do this effectively?

Also, what should be considered a high limit for oil temp? Is there a published number or just a recommendation?

CJ

Mahlon · Post by **Mahlon** » Mon Oct 08, 2007 4:21 pm

240F Max for the oil temp and above 160F will get rid of the water and acid.
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."

captain_john · Post by **captain_john** » Mon Oct 08, 2007 9:14 pm

Great!

Thanks again Mahlon!

CJ

tmbg · Post by **tmbg** » Tue Oct 09, 2007 11:48 am

anyone have any thoughts about the -C1C 200hp Arrow engine? I've been finding them in good shape for reasonably cheap (run out of course) all over the place! It'd be great if that were a good candidate for the RV

captain_john · Post by **captain_john** » Tue Oct 09, 2007 2:37 pm

I was offered a run out 200 horse out of an Arrow. I chose to pass it up because it (to the best of my knowledge) is not a counterbalanced engine. I want the counterbalance for smoothness.

The designation needs a fourth numerical value in the suffix to be a counterbalanced design. The C1C lacks that.

I bet that you could use the M1B FWF kit with good results, but you might want to contact someone smarter than me for that info.

Soooo, I would say that you CAN use that engine! You just need to collate your feces with regards to the peripherals.

CJ

dons · Post by **dons** » Tue Oct 09, 2007 3:28 pm

captain_john wrote:... collate your feces ...

Mahlon · Post by **Mahlon** » Tue Oct 09, 2007 5:43 pm

Later Lycoming powered 200 HP Arrow's used the C1C6 while earlier Lycoming powered 200 HP arrows used the C1C. With a sump and intake pipe swap out to the forward facing variety….. viola you have an A1B6 from a C1C6 or an A1A from a C1C.
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."