Turbo Conversion

[17031]

I have a '67 260B, F.I. non-turbo. It performs great but looking to the future, I plan to fly from CA to Denver to visit the kids. On a flight the other day I flew from San Diego to Fresno at 12,500 (I prefer to fly over the LA air space). The plane performed just fine but I could tell that if I tried to go much higher perfomance would begin to drop off. To go over the rockies it looks like I may have to go over 15,000 and it seems a turbo would be a big help.

Can a turbo be added? Is this an easy installation (from the mechanics standpoint? What is the cost? Has anyone out there done this? If so, was it worth it?

Thanks.

[9089P]

Hi Tim,

Sorry I can't help with the basic questions about doing the turbo except that the "C's" did have that option and I believe 70 or so came from the factory that way. My guess is that the way to go would be to try to buy one of those. Hopefully someone here can answer your question.

However, we have a 260B non-turbo which we fly to Moab UT 2-3 times a year from No Ca and we travel east bound at 13.5 or 15.5 and its no problem whatsoever doing that flight. The wing on the comanche seems to maintain performance better than others as you climb. The preferred altitude for us is 13.5 but that is for our comfort not the a/c's. We wouldn't go to the expense or bother of a turbo.

As for the Rockies, VFR doesn't require 15.5 to cross. It can be done at 9.5 along I-80 no problem. The southern route can be done in a cub so you shouldn't have a problem.

Good luck with the inquiry, Don

[9089P]

Hi Tim,

PS I grew up in Escondido. To go to Denver from Ramona we used to head towards Alamosa, Co (ALS) cross thru the pass just east of there and then turn north to Denver.

Good luck, Don

[David Pyle]

Tim,

I've owned (and sold) quite a few 260B's. Don't believe I have ever heard of one that had (added) a turbo. Yes, there were a few factory 1970-72 turbo'ed 260C's, and several are for sale. Lot's of turbo'ed Twin Comanches.

Quite a few 250's have added the Rajay turbos.

Suggest you make the CO trip to decide what you need.

[T210DRVR]

I think you'd find it far easier to sell your plane and acquire one that has a factory turbo. Retrofiting your 260B would be tough if not impossible.

I've travelled as high as 17,000 ft in my 180 Comanche. I'd think you would have adequate performance from your 250 on the trip you describe. I've travelled over the Rockies several times in a N/A 230 HP 182.

To me the real value of turbos is for weather flying where getting on top or through an icing condition may be necessary.

My $.02,YMMV

[Zach Grant L1011jock]

Tim,
Mid teens is NO PROBLEM on any of the Comanches. Yes, power does drop off, so technique wise, you need to follow a cruise climb profile, not a hang it on the prop type climb, but you will find that the wing will yield about 500 fpm all the way up, even at gross. Frankly the Rockies are no place to be needing to go IFR in any light aircraft not capable of mid flight level performance IMHO. In a Comanche, go VFR in the daylight, and enjoy the view.

I ran my normally aspirated twin at 16K all the time, and have had my 180 to 17K on several occasions. Yes the turbo goes faster when you get to altitude, and climbs a bit better getting there, but remember, the Comanche was designed for 180 hp (and did quite well with 180 hp if I may say so myself). When you can only pull 70% power on the 260 (about 8000'), that is still 180 HP!

Normally aspirated Comanches are some of the best, if not the best high altitude performers in their category, and it is all to do with the wing.

-Zach

[17031]

Thanks all. I haven't tried taking it up to the mid teens and I duess I made some assumptions that aren't correct. I trained in a Cherokee (I'm a new pilot) and the Comanche was like climbing into a rocket (a little writer's perogative here). When leaving Ramona the other day I wanted to get up over 10k asap to go over the LA airspace so I "hung it on the prop". At one point I was climbing a little over 2k fpm. Even at 12.5k, I was climbing at almost 1k fpm. After reading these responses I went back and read the charts in the POH and sure enough the plane is performing excatly as it should. I only have about 70 hours in the 260 and already I'm spoiled.

[T210DRVR]

Single Comanches are more comfortable in climb with indicated airspeed of 100 -110 MPH. Like Zach says, they'll surprise you with their high altitude capability. The wing is wonderfully efficient.

For VFR flights with just two people and bags I'll chose my 180 Comanche every time. My Twinkie is saved for weather flying or needing to haul a bit more.

[Zach Grant L1011jock]

For VFR flights with just two people and bags I'll chose my 180 Comanche every time. My Twinkie is saved for weather flying or needing to haul a bit more....now that sounds familiar...
-Zach

[Tony Scarpelli]

[Zach Grant L1011jock]