The making of a super "c"

[Mooneyjet]

Hey guys has anyone gone throught the the converting a m20c to an io-360. Any pireps with regards of performances and what the stc consist of. Thanks

[TTaylor]

Can not imagine this is worth doing. Sell the C, buy an E. Or, buy an E. Take everything out of the C you want and put it in the E and then sell the C.

[flight2000]

Not that I'm aware of.  The C and E models have held their values pretty well, so agree that it would be cheaper to just upgrade to an E or J model versus the pain and expense of going through an STC or field approval to have the IO-360 hung on a C. 

 

Also discussed back in 2011.  The search function is your friend...

 

http://mooneyspace.com/topic/3260-m20c-to-200hp-io-360-conversion-pireps/?hl=%2Bconvert+%2Bio-360#entry38430

 

 

Brian

[Oscar Avalle]

not really worth while...just upgrade

[Shadrach]

I believe Lasar has the STC to do it and it has been done. The only time it would remotely make sense is at overhaul.

[orionflt]

I agree with everyone, not worth it, but if i was going to go thru the exercise of upgrading engines I would go with the IO-390 (210hp) and do a field approval (no STC for the C model yet), all the upgrade data is already out there so the field approval should be easy....depending on you FSDO that is and you might be able to get some help from Lycoming.

[John Pleisse]

Sure it's not worth it....of course it isn't. Neither is putting a nice autopilot in a "C". If you like the plane, you're in deep and want to keep it, I say go for it. 3 hurdles: finding a good core, engine gauges, cowling induction. The STC and hardware are under a thousand bucks. Go for it. Another great Mooney made better!

[BigTex]

Sure it's not worth it....of course it isn't. So is putting a nice autopilot in a "C". If you like the plane, you're in deep and want to keep it, I say go for it. 3 hurdles: finding a good core, engine gauges, cowling induction. The STC and hardware are under a thousand bucks. Go for it. Another great Mooney made better!

+1. I couldn't of said it any better.

[John Pleisse]

It'll take a new fuel boost pump, too, I think.  Consider installing a PowerFlow exhaust, instead, on your 0-360 as a way to increase power and performance.

 

Jim

 

It does.

[N33GG]

I am pretty sure Don Maxwell has done this before.  If I ever decide to do this, and I might, I would go straight to Maxwell to get it done right.

 

In answer and support of the above posts... Yes, it's not worth it.  But I would really like the IO-360 engine.  My airframe is perfect, one of the straightest flying aircraft I have ever flown.  And I have spent quite a bit getting it like I want it mechanically, and avionically (if that's a word) as well.  Simply stated, I know what I've got, and all I would want is to change the engine.  Might cost more that it's worth, but debugging another aircraft to this level could be expensive as well.

 

FWIW

[N33GG]

FYI... It is my understanding that it takes an E Model engine mount and cowl.  And certainly a lot of other things as well...

[jwilkins]

When Gordon Baxter was researching Mooneys he wrote about why he bought a C instead of an E in one of his Bax Seat columns.

I believe it was Charlie Dugosh who advised Gordon to buy a C instead of an E.

According to Gordon's adviser, there was very little performance difference, and they felt there were, at the time, some advantages.

The vintage Flying magazines are on line at Google Books. It might make interesting reading for you.

What better way could you find to spend an evening than reading the Bax Seat columns looking for the Mooney ones?

It may not have any bearing on your decision, but would be a fun research project.

 

I had a 62 C, a 67 F, and now a K.

The C was the most fun to fly. 

The F was a little faster, had more range, and better avionics. I did not enjoy having it here in Prescott AZ on the really warm summer days. Start out at 5K field elevation and add in 90 to 100 degree temps and, even lightly loaded, we used to search for thermals to get to cruise altitude .

 

The K is a fantastic AZ / Western traveling machine.

[Mooneyjet]

Hey guys thanks for the feed back, my engine is getting close to overhauled so I'm starting to look at my options if any out there. I see Cessna is refurbishing old c172, with new engines and avionics see avweb latest news, I don't see why we can't do that with the vintage mooneys my "C" is a low time airframe and zero corrosion wich in my opinion should out last me. Therefore an upgrade to fuel injection would be an option that would make since in my case at overhauld time. I be even ,ore interested on the 390 option just because of the option to perhaps run on alternative fuel to avgas, not to familiar with the field option guys could anyone point me towards the right direction I would defenetivily consider that. I know that lot of RV owners convert their 0-360 to fuel injection very easily apparently however not certified. Thank for the positive feed back guys.

[rbridges]

I think it's just the cost issues.  Even people with 6 figure J models aren't jumping on the 390 conversion, let alone people with a $40k C model.  I know the gain against the IO360 is minimal, but you have to look at cost/benefit ratio.

[N601RX]

The most economical way to do this would be to find a E or F that had wing damage and was up for salvage.  You could sell what was left as well as the firewall forward from you C and recoup a lot of the conversion cost.

[Shadrach]

...I know that lot of RV owners convert their 0-360 to fuel injection very easily apparently however not certified. Thank for the positive feed back guys.

 

The RV crowd likes to convert carbed parallel valve O360s to IO's so that they can run LOP. It does not have any affect on power, still a 180hp engine.  The benefit to the angle valve IO360 is the tuned induction and the higher C/R (8.7:1 vs 8.5:1).  Most of that extra 20 ponies comes from the C/R bump.  It is a more efficient engine in a number of ways, intake and injection allows LOP efficiency ratios, Higher C/R pistons make it more thermally efficient.  In theory, for a given HP the angle valve will do the same on less gas.

 

The downside to the angle valve is that it is heavier by about 40lbs IIRC...

[rbridges]

The RV crowd likes to convert carbed parallel valve O360s to IO's so that they can run LOP. It does not have any affect on power, still a 180hp engine.  The benefit to the angle valve IO360 is the tuned induction and the higher C/R (8.7:1 vs 8.5:1).  Most of that extra 20 ponies comes from the C/R bump.  It is a more efficient engine in a number of ways, intake and injection allows LOP efficiency ratios, Higher C/R pistons make it more thermally efficient.  In theory, for a given HP the angle valve will do the same on less gas.

 

The downside to the angle valve is that it is heavier by about 40lbs IIRC...

 

 

aren't the cylinders much more expensive to replace?  Does this factor much into OH costs?  I heard the 390 cylinders are absurd.

[BigTex]

The most economical way to do this would be to find a E or F that had wing damage and was up for salvage. You could sell what was left as well as the firewall forward from you C and recoup a lot of the conversion cost.

So you're recommending the donor plane approach to build out his Super C? What would one expect to pay for a salvage E, F or J?

[Shadrach]

aren't the cylinders much more expensive to replace?  Does this factor much into OH costs?  I heard the 390 cylinders are absurd.

Couldn't say, I've never shopped them, but I'd not be surprised....

[N601RX]

The list price for a IO 390 cylinder is a little over $4100

[Shadrach]

Jaysus! So the cost to top a 390 is about the same as field OHing a 360....screw that!

[John Pleisse]

I have about 10 hours in a C. IMO there is significant difference in climb performance and realistic cruising altitude, compared to the E (never flown an E, I have a J). My earlier "caution to the wind" advice aside, I'd go with the Powerflow exhaust over the new engine purchase. Its the best advice on this thread. Chances are, you could be nearing some exhaust work, making it a better value. You would be adding a mod to your C that could net you returns when you sell. Major OH is a great time to do it and may save you a few dollars. If indeed, the performance between the C and E is more negligible, the Powerflow would close a big chunk of the gap.

 

A fresh OH and a Powerflow together? You would notice it the second you turn the key.

[John Pleisse]

The list price for a IO 390 cylinder is a little over $4100

 

Now add a factory new Top Prop.

[N601RX]

One other thought, the IO 360 rill run LOP and the O360 will not.  If the original poster truly intends to keep this plane for the next 20 years that should be factored in also. What will fuel cost per gallon in 5-10 years.

[triple8s]

I have about 400 hr in a C and it was modified. Had everything a j had but the big emp, longer tail cone electric gear and fuel injection, and really thought about trading for a J at one point. Seemed like the longer I kept it the less advantage I saw of trading for a E, J, or even a K. I went on a trip to KHSE following a K and I made the round trip with no fuel stops. When we arrived at Hatteras I was entering the pattern when 234JP was taxiing to tie down. I was 164kt gs on eastbound run and less than 5 minutes between the 231 and me. On the way home he bought fuel I did not and I beat him to the hangar. So I just really found it hard to part with my antique C model Mooney. I finally broke down and moved up but I went to the big TCM and to tell you the truth unless it's in hard IFR it not really anymore fun to fly than 880, and I won't be visiting any short unimproved strips with the long body. So I guess it's all in what you want. I see nothing wrong with upgrading but be sure it's a step up and not sideways.