C85 Conversion Complete!

[PA1195]

To accompany Scott's welcome reference to Stromberg operation in #22 here's a similar brief on Marvel carburetors.

http://www.kellyaerospace.com/articles/Accessory_AMT.pdf

Gary

[Taylorcrafty]

Hey Tim,

How are you cruising at 120mph with that climb prop?

Only asking because I would love to make mine go faster.

My F-19 cruises at about 90mph (gps) at 2450RPM with the cruise prop.


Also, finally installed the fuel valves. Much better. Thanks!

Get the longest and flattest propeller you can get, I ran a 7443 with a o-200, I started with a a 7446, I gained a lot of climb and it can cruise 105 kias with the last prop I had. I am not sure what my current one will do as a swapped from a Sensenich to a McCauley. The marvel carb is also great because of having a mixture.

[astjp2]

RPM, I am running 2700-2750 and it was a sensenich, I have not tried the McCauley yet. The cruise prop would not turn RPM's, it dropped off at about 2600 with the 7446, the repitch made it a new airplane. The prewar airplanes are quite a bit faster for some reason which I believe is due to the angle of incidence, and mine has covered gear legs and a spinner which helps. Tim

[Taylorcrafty]

RPM, I am running 2700-2750 and it was a sensenich, I have not tried the McCauley yet. The cruise prop would not turn RPM's, it dropped off at about 2600 with the 7446, the repitch made it a new airplane. The prewar airplanes are quite a bit faster for some reason which I believe is due to the angle of incidence, and mine has covered gear legs and a spinner which helps. Tim

What is your fuel GPH like cruising around at 2750? Is it a stock O-200?

[astjp2]

6.5 gph or so

[Taylorcrafty]

6.5 gph or so

Okay. Any other downside to running around at redline all the time?

[TC747paul]

Kerbs
That is one nice looking T-craft, I did the same conversion but added the starter after a near miss propping on ski's.
i think it makes a great plane even better.
Are those 8.5x6 tires?
Did you happen to note the oil temperature delta to ambient?

[astjp2]

Okay. Any other downside to running around at redline all the time?

I never said I flew that way all the time, but the airplane is capable, I flew out of Delta Junction a lot for several years and never had any problems. I would fly to chicken; circle, central, tok , Palmer, fai, anc, Merril, all over and if the weather was good, it I would fly 10 hours on a Saturday because I enjoyed it. I did have a weird vibe at 2300 with the old prop so I either had to cruise at 2150 or 2450 because I did not have a spinner to do a dynamic balance at the time. I have yet to fly the new McCauley. I was able to get a new Sensenich if I want to go ack to that one. Tim

[Kerbs]

Kerbs
That is one nice looking T-craft, I did the same conversion but added the starter after a near miss propping on ski's.
i think it makes a great plane even better.
Are those 8.5x6 tires?
Did you happen to note the oil temperature delta to ambient?

Thanks, I appreciate it. The C85 makes it so much more fun, and it was a lot of fun to begin with. Yes, they are the Dresser 22" 8.50s. I really like them and they have held up well so far.

I did not make not of the oil temp to ambient. I have noticed that the oil temp is coming up a little higher than the 65 which I like, my 65 barely ever warmed up in the winter.

[Laz]

I am considering the same upgrade , but with a battery starter and no alternator.
what king of mags did you use and how was the fit. If you could send a picture that would be great. Where are you located at?

[Kerbs]

I am considering the same upgrade , but with a battery starter and no alternator.
what king of mags did you use and how was the fit. If you could send a picture that would be great. Where are you located at?

I went with Bendix mags. There are a number of pictures under the thread on carb ice continued that I posted recently or let me know if you want something else. I have a spreadsheet of everything that went on it along with the cost. PM me if you would like me to send it.

[Robert Lees]

I am considering the same upgrade , but with a battery starter and no alternator.
what king of mags did you use and how was the fit. If you could send a picture that would be great. Where are you located at?

We have a Pitts S1S at my airfield that used to have battery starter, no alternator (or generator) for weight reduction.
It makes sense...you have the advantage of battery start, without the complexity & weight of alternators, voltage regulators etc.

Just one impulse mag, any brand, makes the whole process easier.

Plus, an S1S is easy to hand-swing if the battery gets cold, or flat.

[astjp2]

Dual impulse slicks.

[CaptainJon]

What is the core charge in addition to the $982.80 for the Marvel/Tempest? Suppose they will give me a deal on two of them? I've got two Strombergs.............

Cheers,

Jon

[astjp2]

For what carb? They list the core on spruce from what i remember it is a foot note