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Engine basics => Engine set up tips => Topic started by: Paul Allen on May 27, 2013, 01:44:29 AM

Title: Torpedo 40
Post by: Paul Allen on May 27, 2013, 01:44:29 AM
Can anyone give me some info on this motor,does it have a model #,were they any good?
Its twin ball race with dykes ring has a very large venturi opening.
thanks
Paul
In OZ
Title: Re: Torpedo 40
Post by: Reptoid on May 27, 2013, 02:33:41 AM
     Since it has the wide bypass and cast wedge head, most likely "Series 69" front rotor .40. They did make venturi inserts for these and if I remember correctly they were .270"-280" I.D.
    These were very powerful and popular for competition in their day in Free Flight and controline racing, Still quite popular in free flight. Pretty much ruled until schnerle ported 40's came on scene.
    Making sure you have a perfectly round and well fitted ring is key to performance.
Title: Re: Torpedo 40
Post by: M Spencer on May 27, 2013, 10:31:50 AM
Id used one in a clean 57 Oz plane , open Exhaust . on a 11 x 5 . Worked pretty good . steady rpm's . ' p ' head blew plugs though . ( stamp on front - same bowl / squish band  dimns as ST 40 & 46 . std.   )
Likes a drop of nitro , good tourque . well behaved .  Peak H.P. rp,s 16.000

here a road test of a series 70 R/C . Near identical dimensionally . http://sceptreflight.net/Model%20Engine%20Tests/K&B%2040%20Series%2070F%20RC.pdf
head in pic isnt the ' P ' ( Pylon ) that matches the Super Tigre 21 / 40 combustion chamber . & the Irvine 40 . Thats derived from these , he was the U.K. agent .
Piston Ring & gaskets amoungst other parts interchange . Were a hot Rat Race ( Grymzyph ) and the pylon motor before the sturdyer G-40 / X 40 super tigres .
(http://static.rcgroups.net/forums/attachments/4/5/9/8/2/a4478000-60-grmzpf.jpg)

(http://static.rcgroups.net/forums/attachments/4/5/9/8/2/a4478104-99-Grmzpf_MAN_plan.jpg)

(http://static.rcgroups.net/forums/attachments/4/5/9/8/2/a4478139-206-Grmzpf_aeromodeller_plan.jpg)

Trans Atlantic Fame & Glory .  %^@
Title: Re: Torpedo 40
Post by: M Spencer on May 27, 2013, 10:52:30 AM
This Blokes Responceable ! http://modelenginenews.org/people/images/WisObit.pdf

its a derivative of this sucker ;

(http://sceptreflight.net/Model%20Engine%20Tests/K&B%2029R%20Page%201.jpg)
http://sceptreflight.net/Model%20Engine%20Tests/K&B%2029R.html

(http://www.modelaircraft.org/plans/images/1987/573.jpg)

these planes arnt sutable for STUNT though .  :## D>K

Torpedo on the MC 72 .

(http://www.clstunt.com/htdocs/dc/user_files/20307.jpg)

This One IS . Very .
Title: Re: Torpedo 40
Post by: Jim Thomerson on May 27, 2013, 02:25:04 PM
The later model 4011 is a favorite stunt engine.  I have  a front end like yours, but have never put it on an engine.  I'd say start with an 11 x 5 and change props and/or choke down the venturi if you have a problem with wind up.