Step 1: I've wanted the same plane for 3 months. That was the first requirement by the wife. I'm set on either a C 150 TD or a C140/120.

If I go the 150 route, it is pretty easy, as I am pretty much set with the O-200.

If I go with a C 140, there are a bunch of engine choices. I know a lot of you currently fly or have flown these. So I have two concerns:

1) Availability and cost of engine parts/repairs
2) Performance differences

So I think my main engine choices are the C-85, C-85 with crank conversion, C90, O-200, and O-235. I'm not interested in an O-290 due to the parts availability issues. O-200 would be my first choice, as it should be a decent performer, and parts are readily available.

C140s with the C85 and C90 are available for sale all day long. I know nothing about parts availability and cost, or the performance. I live in Massachusetts, so I don't need to leap off a 300ft strip. I am mostly concerned with cruise speed (I would like to cruise above 100mph if possible).

So if you are familiar with one of these engines and can answer #1 and #2, I would appreciate it!

Thanks,
Jesse

I can not answer #2 because I don't fly a 140 but I have a C-85 with the o-200 crank in my plane. It is still only certified at 85hp but when I spoke with the guy that developed the STC he said the engine they used to get the STC dynoed at 106hp. The only hard part to get for the C-85 is the crank; I don't know why you'd use a 85 crank when you could build a stroker. I run what is considered a cruise prop for my plane (7151) and turn max allowable static RPM, 2255 so it is closer to a climb prop than a cruise for this engine. The C-85 is lighter than a O-200 by about 20lbs. In my completely uneducated and totally biased opinion you can't beat a C-85 stroker unless you jump to a O-320.

I have a lot of time in my Dad's 120 with an O-290D (125hp). I know you said you weren't interested but figured I'd chime in anyways. I always had a blast flying it. It will cruise at 125mph with 8.00x6 tires on 7gph or less and climb like a bat out of hell. I know legal usefull load is limited but I can tell you it will haul whatever you can stuff in there. I remember heading to Idaho on a camping trip with my Dad one time, we had full fuel and camping gear in the back. We were climbing out at 1000fpm at 100mph, hard to believe, I know. Do a search if you haven't already there are some other good threads from the past with more info.

O-235 is heavy.

O-200 is 1.6 pounds heavier than the C85-12F, and roughly half a pound heavier than the 85 stroker.

I've flown a 140 with the 85 stroker, and the performace is decent -- I like the 85 stroker. Top speed at WOT was about the same as an O-200 powered J3.

I've flown an O-200 powered J3 side by side with two 85 stroker J3's, and the O-200 smokes them, both in climb and top speed.

In short, I'd go with the O-200, because the greater valve lift provides better breathing, and the O-200 develops more torque and power than the 85 stroker.

I need to learn to research better what I hear at the airport. A F1 guy I was talking to a while back said he starts with a C-85 when he builds his race motors because they come in 20# lighter than if they start with a O-200.

According to the TCDS the C-85-12, -14, -15 weigh 180# and the O-200-A, -B, -C weigh 190#. The O-200-D, and -X are much lighter at 176.5#.

I don't know what accessories the O-200 uses but the generator and starter on my C-85 weigh 16# each; maybe that's why JimC reports numbers that are so close

I owned a O-235 C140 for a number of years, and will agree that a O-200 would be a better match. I've flown all three, a C85/O200/O235 and there are no huge differences in power between the 3 (all 3 had cruise props). A C85 will drink a lot less gas than a O235.

There are a lot of 150-horse C150TD's out there. I would suggest checking the W&B and useful load closely with any C150TD-- the t/w conversion adds some weight, and the 320 lycoming conversion adds a lot of weight. If you look at any C150-150C models (trike or taildragger) with a bigger engine,
check for compliance with AD 86-15-07 which addresses CG & useful load.
C150/150TD's are heavy, but they can provide good performance & be a hoot to fly. Better count on spending upwards of $30K though. You can get into a pretty decent 4 place airplane (like a Pacer or Stinson) for the same money.

My '46 140 has the stroker (never heard it called that before) c85. Its a compromise. I was able to keep the same engine mount and prop as before but got more power on climb out. I switched to a 7150 prop which cruises at 110-115 MPH. I trained in an 0-200 equipped 140 and could barely tell the difference after I switched to my plane.

With the exception of the vacuum pump, the 85-12 and the O-200 use the same accessories. The following tabulation is based on Continental's published weights, but with Slick mags, and the vacuum pump has been removed from the O-200.
Engine Weight
C85-8 185.82
C85-12F 191.93
C85-12F Stroker 192.97
O-200 192.87

Continental reports the basic dry weight of the C85-12F as 168.6 pounds, and the basic dry weight of the O-200 as 170.18 pounds. The O-200 crank is 1.04 pounds heavier than the C85-12F crank.

If you have broken a C85-12 case at the center crank bearing stud, ( wish I knew how
to post pictures), you would want the 0-200 with thru bolts.
Other than that, you may be able to swing a longer prop with the C85.
Dave

A Mac 7535 is legal on an O-200 on a 150 sealpane, but not necessarily on the 140.

Thanks guys!

The savings in weight isn't a huge issue for me, as me and the wife weigh 270 combined. Sounds like the base C85 (non-stroked) wouldn't be a horrible choice. I'd only want an O-200 150TD. I'm trying to get a plane that offers flying on the cheap. So O-200 or smaller would be the most economical choice. Mostly I just want to do short flights within a 100 miles.

For the C85 and C90, are parts still made for those engines, or is there at least a hefty stock of all parts? Are they reasonably priced? I'm thinking more and more that a C85 might do the job, but just don't want to be stuck if I need something for it.

Thanks again!

I had a 120 with a 0-200 and it was a good combination I cant remember what prop it was but it crused over 100mph statute on less than 5gph. (canadian gallons)
Parts for any of those little continentals have not been a problem in my experience.
The 0-200 is beefier in a couple places which is nice any of them will need the valve guide once in a while expecially on mogas.

+1
Most parts in the C85, C85 stroker, C90, and O-200 are interchangeable. Availability is not a problem. Quite a few parts are interchangeable with the A65 as well.

There is a substantial increase in performance from the 85 to the 85 stroker, and almost as much increase from the 85 stroker to the O-200 if appropriately propped to take advantage of the O-200's rpm capability. With an 85, the 140 is a bit of a ground lover, though not as bad as an Ercoupe.

There is a Continental Service Letter detailing parts required in conversion of a C85 to a C90, which differs from the stroker conversion by also including the higher lift C90 cam and lifters. One extra throughbolt can be easily installed in the C85 case. Two is problematic due to differences in the oil passages. I would not install the second extra throughbolt, but would install the first.

Very cool. Can't wait to be able to join the "Post a Picture of Your Plane" thread. I'll be like one of those super annoying people on facebook that shows a new picture of their baby every 5 seconds that no one cares about because everyone else has done it a thousand times and I just think I'm special...

That is reassuring about parts. I know people are still putting C85s in Cubs, so figured it couldn't be that difficult to find parts. Maybe I can find a C140 airframe and put an O-200 on it.

The 85 stroker is easier.

whee wrote: I need to learn to research better what I hear at the airport. A F1 guy I was talking to a while back said he starts with a C-85 when he builds his race motors because they come in 20# lighter than if they start with a O-200......

I wonder if they start with a C85-8 (non-electrics)? I'm not familiar with the F-1 rules but you don't need an electric starter & lights for day-VFR around the pylons at Reno.

PilotRPI wrote:..... I'd only want an O-200 150TD. I'm trying to get a plane that offers flying on the cheap. So O-200 or smaller would be the most economical choice......

I've seen some really nice looking early "fastback" C150TD's with the stock O-200. They look like baby 180's (if you squint a bit) and perform reasonably well. I've seen them for sale in the low-to-mid 20's. Comparable to a C140 except bigger more effective flaps and also bigger more effective ailerons, plus all metal so you can keep it outside. A little heavier than a 140 but a little higher gross too (1500)-- 1,000# empty weight (not unrealistic) gives you a reasonable 500# of useful load. Plus it's a little unusual which can be fun.

The fastback 150 TD is the one to get. You can put on C140 gear, so it handles on the ground very similar to a 140. The later 150s use texas taildragger conversion or similar, and the shallow deck angle on the ground can make things a bit tricky for takeoff and landing, so I hear.

Since we've been talking about fastback 150 taildraggers I thought I would share this pic. This 150 showed up at Rio Vista today, its one of the nicest looking ones I've seen.