V. Sharp

Gentlemen;

A friend of mine has come up with a Cox .09TD R/C. It has an adapted glo plug head instead of the glohead. Lots of compression.
We have not been able to come up with any information on this engine. Is it relatively rare, or would it make a good engine for flying? How would the power output compare with a modern multi-bypass ported engine of comparable size? Anyone got any information?

Any help would be appreciated. Thanks

An old timer,

Vaughan

mylamo

My Feedback: (1)

The Cox .09 compares very well, in fact you will
have a hard time comming up with anything that
comes close as far as power / weight is concerned.
I wouldn't have a comment regarding the head
conversion though.
Ralph

flyinrog

My Feedback: (1)

yep, all of the TD series are screamin engines....loud, but screamers...Rog

ffkiwi

As far as I know this engine was produced about the same time as the TD 05 R/C and for a similar short length of time [leading one to speculate that perhaps they didn't perform as well as expected-or alternatively that Cox didn't sell as many as they expected to!]
The adverts I saw showed them fitted with a silencer and conventional intake carburettor-and the plug head. I would say-almost as a certainty-that both the silencer and the head would have come from the Queen Bee 074 reed valve engine-since this used a cylinder with Cox 09 external dimensions. Now I expect that the engine may have been detuned a little bit in the quest for better handling and idling-for a start they would have had to eliminate the subpiston induction-otherwise the power loss on fitting a silencer would have been huge-and probably the effective venturi size was reduced in comparison with the std TD09-plus the std plug head would be likely to reduce power a bit in comparison with a std TD 09.
So to sum up-it will be a very light R/C 09-probably less powerful than a TD 09-but probably producing anywhere from 0.2-0.25 BHP at around 15,000 rpm [I'm guessing at these figures-the TD 09 is good for 0.3BHP at 20,000 rpm]-so comparable to the OS Max 10 FSR's, Magnum GP 10's etc
There is only one other engine out there which would be directly comparable and that is the Cipolla Junior 09-which are a bit thin on the ground-the competition PF7 ABC version was more powerful than the TD 09-but as far as I know was not produced in an R/C version, whereas the standard model was.

'ffkiwi'

Jim Thomerson

In the late '90's a go-fast engine guru I knew used them in an 09-10 size RC pylon racing class in preference to other available engines.

V. Sharp

Gentlemen:

Many thanks to you all for all the information!! I appreciate all the help.

Vaughan

V. Sharp

Gentlemen:

Many thanks to you all for all the information!! I appreciate all the help.

Vaughan

flyinrog

My Feedback: (1)

I forgot they made that in .09..I have the .05 version,, I was thinking of the TD .09 with the throttle ring....Rog

somiss1

My Feedback: (5)

Vaughn, I have a NIB TD .09 R/C. The engine came with a regular short plug instead of a glow plug head. Thank goodness as replacing a regular plug is cheaper and easier to find. The recommended prop is a 7/3.
Frank

jigsawyer

My Feedback: (31)

Hi Vaughan,

Get an old TD .09 head adapted for the (Henry) Nelson plug and it'll put out more power than stock! Conversion cost is around $10, and the Nelson HD plugs are $3.50 and last forever!

How y'all doing???

Ralph Wenzel

AndyW

My Feedback: (1)

Vaughn,

How did you make out running your TD .09RC? Can you give us RPMs, prop, fuel?

FYI, I converted a stock TD .09 to RC with a custom made muffler and by adding an MVVS .09 throttle.

You can see that run here.

http://www.youtube.com/watch?v=o-uvAb-vQgM

It sounds a little ragged in the clip, I found out later I had it a bit overcompressed with 25% fuel.

BTW, I've found that the Cox 7 X 3.5 prop is superior to any other on this engine.