Well, I’ve decided to treat myself.  Since I’m still a re-tread beginner, I figure I don’t need a high-zoot engine at my stage of the game.  But I’m a sucker for “stuff”.  I see no real need for an engine tweaked by one of the pros, ‘cause it’ll be a while before I am good enough to need it, but I just want one. 

I have two O.S. .40 engines that I want to convert to CL.  One is a .40 FP and the other is a .40 LA.  I’ve read the .40 LA isn’t as good as the .46 LA as far as run performance, but not so bad as-is.  And I’ve read all the posts about the .40 FP running away unless I do A-B-C, or J-K-L, or X-Y-Z.  Since it’s gonna take more than just installing the stock OS venturi and needle to make the .40 FP a good stunt engine, I figured I’d send the FP to Tom Dixon for his treatment if he can fit it in.

So, is there any reason that my choice is poorly thought out, and that I should send in the LA instead?

Mark

Ditto ;

So many things are climatic , site alt etc etc . Someone can have one ' spot on ' where a identical one can be a dog .

Bit like that with cars and motorcycles , Some Peoples arte dogs and have you ever noticed mine are much faster .

GOOD OIL so ya dont tear the guts out of them . After Run oil or get rid of the corrosive nitro residue if not flying again the next day .

Having ' suffered a Magnum GP FP 40 Clone , and a S/H FP 40 , ive another ' in the mail - on its way .

Seems some say the BIG R/C muffler , particularly if your into profiles , isnt a bad idea . One can cut half thru the bolts at the join face ,
if the earth hasnt stopped getting in the way of your aeroplane. & carry a few spares .& spare props .

Something fairly solid to start with isnt to b ad an idea, till youve got things figured out a way .
Undercarrages on profiles can absorb a lot of pounishment , and timber props dont take fingers off like some others .

If you start getting realy keen you could whittle out the FP head ( Putting a custom one on my Ball Race FSR 40 Turned it into a steady 4 stroke set up . maybe.
You cant trust these FSRs Either .

And bunging the boost port in the 40s is no big deal , a 1/4 x 1/8 balsa 1/2 long about covers it , with a drop of epoxie to cure - if your starting to loose sleep .

The STIFF 11 x 4 Tornado / Grish props work well on em , if you find a bag at 4 2 Ea .

Most OSes will run fine without nitro , too . Wasnt Available where I was till the Drag Racing took hold & they satarted importing it .

So you can plough your own furrow , which isnt the same as digging a hole & burying yourself .

Theyve both got plenty of power . My Stock FP pulled the 65 Oz 68 Span ( only abvout 600 sq in ) as well as a ST 46 , on a 12 x 4 Tornado, and chip / tounge muffler .
Not sure how the old Iron Piston / Liners like having the heat held in there tho , was that or corrosion on the crank web going thru that loosened it of in the bore .

Early FPs are IRON , unhardened ?? steel liner , so need good castor . Old Days people would bake OS liner & piston three times , ( 1 Hr, cool , repeat,  x 3 )
then lap in with toothpaste , according to a few F M Articles , stabilises & Hardens them . Later round case FPs might be ABC , if its got ' ABC ' on the BOX . 

Let us know how you go . Beats watching the Television.