320 or 360?

[s10sakota]

Has anyone ever installed and flown with a 160 hp O-320 and then wished they went with the O-360?

Did you swap? Was it worth it? Performance difference?

Thanks!

[N941WR]

I think the quest should be, "Has anyone installed an O-360 and wished they had installed an O-320?"

[L.Adamson]

Originally Posted by N941WR

I think the quest should be, "Has anyone installed an O-360 and wished they had installed an O-320?"

The answer would probably be no. More power when you need it, and throttle back to get the same fuel economy.

I do know lot's of 0320 owners who wanted 0360's. they were mostly in 6's..........at the time.

L.Adamson --- 6 with an 0360

[N941WR]

Let me back up a bit.

When I first built my RV-9 I installed a 135 hp O-290-D2 in it. It was a great engine and a great match for the -9. I could cruise it at 140 knots / 165 mph all day long at 65% power and still climb it at 1600 FPM with full fuel, full seats, and baggage while burning around 7 GPH.

It really did very well with the small engine.

However, when I trashed that engine I found the cost of an O-360 ECi kit was only $500 more than an O-320 kit AND the 360 was only 20 lbs heavier. Thus, I installed the larger engine.

As for performance, I can easily pull the throttle back and match the speeds and fuel burn of the O-290 only I can now climb faster and cruise faster, if I want to.

My typical 65% cruise speeds are around 154 knots and I can run lean of peak due to my dual electronic ignition and burn 6.5 GPH.

The next thing to take into account is resale value. The 180 hp (I)O-360 is the "standard" engine for the -7 (and -8) and anything less can really impact the value.

Regardless of the engine, make sure it has the hallow crank so you can run either a FP or CS prop. Heck, you can even start with a FP and change it to a CS prop as your budget allows.

[RV Wannabe]

As a RV wannabe I would be currious to hear from some -4 owners on this subject. Doing my reasearch when I was in the marked came up with the 320 owners really liked it because of handling reasons. For handling the 320/fp wins, for speed and maybe W/B if you carry a heavy passenger the 360/vs wins. In an RV-4 of course.

Do I have this right?

Mark

[s10sakota]

Thanks for the replies so far guys! I do know one thing, I will never install a cs prop. Yes they are awesome, my goal for this RV-7A is lightness and simplicity!

The reason I ask is because I may be able to get an O-320-ED2 for free....but it has a cracked case.

First my buddy has to make sure I can get the engine, but if I can, I'm trying to decide if it's worth it to fix this one with a new case and the 160 hp pistons, or just go with the 360. I may regret not having the power later!

[N941WR]

Originally Posted by s10sakota

...The reason I ask is because I may be able to get an O-320-ED2 for free....but it has a cracked case...

I have a "free" bulldog, the dang thing is the most expensive dog I have ever owned!

A friend bought an O-320 core for his -9 project at a great price, $500, IIRC.

After sending all the parts off, having the case converted to dynofocal mount, replacing the parts that needed replacing, he could have bought a O-320 ECi kit engine for just a few grand more and EVERY thing would have been zero time. He is happy that he has learned a lot but not happy that he could have had a new engine for about the same $$$.

[s10sakota]

Bill,

That's the kind of info I need! Thanks. I have no idea what it would cost to have this engine rebuilt but like you said it may turn out to be no deal at all.

It just may be better to look at something like the ECI kit.

[L.Adamson]

Originally Posted by s10sakota

Thanks for the replies so far guys! I do know one thing, I will never install a cs prop. Yes they are awesome, my goal for this RV-7A is lightness and simplicity!

Just something to keep in mind, and especially at airports that are quite a bit higher than sea-level. You'll be thinking the "lighter" aircraft is going to be the performance king. And then you'll fly with someone who has a C/S, and wonder why yours seems like a "slug" on the takeoff roll in comparison. RV's really aren't slugs............but you'd notice the difference quite easily! MY take, is that I never want an RV without a C/S.

L.Adamson

P.S. --- the only time a C/S is not the one to have.........is if you prop strike it...

[N941WR]

Good choice on the FP prop thing.

Remember, despite LA's rants about CS props (here is mine for FP props), while a CS prop RV will outperform a FP prop on take off, even at sea level, your RV will still out run any factory plane out there.

I would not be afraid to take my RV, with its cruise prop in or out of any field a CS prop guy might go into.

Just like the engine choice, remember, the 150 HP O-320 is a great engine for a FOUR place airplane and you are going to stick one in a light two place craft, it will go like stink. The problem us RV guys forget is that we only tend to compare RV's to other RV's and RV's have unreal performance. If you compare a heavy 150 hp RV-6 with FP prop to a F33, the RV will hold its own, except for the two missing seat thing.