Lycoming 0320 question

[JimB]

For you engine guru's out there. I have access to a first runout O320 A1A. Can anybody give me any advice about the sutibality of this engine for a RV7? Thanks.
Jim

[Mel]

O-320-A1A is 150 hp @ 2700 rpm, 7:1 compression, conical mount, fixed pitch. It will work fine in a -7.

[Low Pass]

Well, you could probably find several hundred replies on this basic topic buried in here. But, IMO, the 150-160 hp engines suit RVs very well. You'll still be outperforming spam cans dramatically - even with less than 200-hp. Yes, it's true!

Also, the early/original RVs were intended for -320s, AFAIK. So there's nothing novel or new about using them.

I have a 160-hp on my -8 and find it to be just fine. 80-90% of my flying is solo and the tanks are somewhere in the 30-80% full range. This is a good combination for my flying mission.

Who wouldn't want 200-250-hp out front? In my case, the engine deal I found was just way too good to pass up.

One RV angle to seriously consider is indeed the simple, light one. Put a -320 on the front of a light airframe with a coarse-pitch wooden prop and go fly. You'll have a max speed of 200-mph, +/- a few and save a lot of money/weight in the process.

Last, although most hopefully will never have to find out, having the lighter plane will help should you have to make an off-field landing. This is something very clearly demonstrated back in my old RC days. The lighter the plane, the less damage that would occur with a crash. It's just physics.

[osxuser]

I would consider upgrading it to a 160HP with slightly higher Compression (still a stock configuration for some O-320's) and go with a Sensenich to keep the weight up a little. Should work OK, might have limited baggage weight is some configurations due to a aft-ish CG because of the lighter engine. I don't remember if the O-320A1A can be configured for a CS prop or not, but if it could, a Harzell would help out that situation.

[JimB]

thanks for the response guys, I'm a ways away from making the decision but I appreciate your input. I'll start looking into overhaul costs etc. I'm definitaly considering the 160 hp conversion. I belive the A1A has a hollow crank but because of cost I'll probably stay with a fixed pitch.

Speaking of which, does anybody know anything about prince fp composite props?

[Mel]

The A1A does indeed have a hollow crank, but it has the wrong front main bearing. It can be converted but it is a VERY extensive conversion.

[JimB]

Thanks Mel, extensive modifications usually mean extensive $$ so I'll keep looking. I don't think I want to go with less than 160 hp.

[Mel]

Wait. Don't misunderstand. It's a great engine for F/P. The extensive conversion is for constant speed.

[RV8iator]

JimB wrote "Speaking of which, does anybody know anything about prince fp composite props?"


I have a prince prop on my RV8 with an IO360A1B, 200 HP engine. The prop is beautiful to start with. I had a 68-80 on it initially and was just a little bit too fine of a pitch. I talked with Lonnie Prince and told him what I was getting in cruise, wide open, static, etc and he decided to up my to a 68-83 composite P-Tip wihich I now have.
Initial results are much better, although, not as nice as a constant speed prop would produce. However, I'm in at less that 1/4 of the weight of a Hartzell, and 1/4 of the price of a Hartzell and none of the maintanence costs. So..tradeoff's. You bet. I still cruise at 167 knots TAS, 8-5 to 9.0 gph, Solo climb of 1700 fpm. Take off roll is longer that constant speed but not terrible, approximately 7-800' conservatively, so not bad.
I have been extremely happy with Lonnie's service and product.
I even bought the 68-80 prop to have as an extra in case I ever want to just play around home base. Take off's and Climbs are great just a little too many revs in cruise.
e-mail me if you have any other questions about the Prince Prop.

[JimB]

I see, I thought maybe you ment the bearing was wrong for the 160 hp conversion. I vaguely remember some 0320's had tha problem.