Webra 160; was: Mintor 1.70

[Jerry Budd]

That's cool.

I've never peaked the Webra 160 so I really can't say what the max 
rpm is on a 17x12.  I do know that when Tony Frackowiak was bench 
running his on 15% Magnum the pipe slipped out of the coupler on him. 
The engine kept running so he tached it and there was no change in 
rpm.  It's clear the pipe doesn't contribute much, if anything, as 
far as power goes, it just muffles (one look in the exhaust port 
explains why, the exhaust timing is very conservative). The total 
lack of pipe jump makes it extremely easy to manage speed with the 
throttle (especially so with the MC carb).

I like to refer to it as a big control-line motor.   : )

Good luck with the Mintor's, they seem like great motors too!

Thx, Jerry


>The Mintor engine on the Mintor pipe is not tuned for max rpm.  If you
>recall a post of mine a while ago i found that I could get 8600 on a 17x12
>with 10% and I didn't ever peak out the rpms during my test, just adjusted
>tuning length.  The factory setup gives the engine good midrange and it
>doesn't go lean when you go to full throttle on an upline.
>--Lance
>
>----- Original Message -----
>From: "Jerry Budd" <jbudd at QNET.COM>
>To: <discussion at nsrca.org>
>Sent: Monday, August 11, 2003 10:47 PM
>Subject: Webra 160; was: Mintor 1.70
>
>
>>  That's pretty good, the best numbers I've heard yet for a 3M-170.
>>
>>  For comparison my Webra 160 turned the APC 17x12 at 8500 rpm at the
>>  Fresno Contest in June and then again in 104 degree heat at Riverside
>>  on the 4th of July.  That's not peak rpm but the flight setting which
>>  was a bit rich (new motor and all).  Magnum #1, YS plug, ES-2C140L90
>>  pipe set at 23-1/4" baffle to plug, stock 1.75" rise Mac's header, MC
>>  carb.  The motor is timed so that it doesn't come onto the pipe at
>>  all (i.e., NO pipe jump), and the throttle response is linear from
>>  idle to full power.  It's also ultra quiet on the ground (under 92 db
>>  at the Nats) and in the air.
>>
>>  Tony Frackowiak's running the same setup in an Alliance on Magnum 15%
>>  fuel and turning 8200-8400 (again set a bit rich).
>>
>>  I can't imagine what else anyone would want out of a motor.  It's
>>  essentially perfect.
>>
>>  Jerry
>>
>>
>>  >My 1.70 hit 8200 rpm with 10% magnum, APC 17X12 regular, at the
>>  >Lubbock contest. It was hot and high, reports were that it was like
>>  >being at 7200 ft.
>>  >
>>  >
>>  >
>>  >Gray Fowler
>>  >Principal Chemical Engineer
>>  >Composites Engineering
>>  >
>>  ><rcaerobob at cox.net>
>>  >Sent by: discussion-request at nsrca.org
>>  >
>>  >08/11/2003 10:49 AM
>>  >Please respond to discussion
>>  >
>>  >         To:        discussion at nsrca.org
>>  >         cc:
>>  >         Subject:        Re: Mintor 1.70
>>  >
>>  >
>>  >
>>  >HO-LY-COW !  That's a pretty beefy setup, for sure.  10% Nitro?
>>  > You're kiddin', right??
>>  >
>>  >Bob P.
>>  >>
>>  >>  From: "Wayne Galligan" <wgalligan at goodsonacura.com>
>>  >>  Date: 2003/08/11 Mon AM 11:27:50 EDT
>>  >>  To: <discussion at nsrca.org>
>>  >>  Subject: Mintor 1.70
>>  >>
>>  >>  Just a few notes on my initial test and break-in on this engine.
>>  >> It has not been installed in my plane as of this writing but I
>>  >>cant wait.
>>  >>
>>  >>  3M 1.70 stock header
>>  >>  10 % Magnum fuel
>>  >>  Bluebird c.f. 2-stroke pipe  24.25" center of head to 1st baffle.
>>  >> Total length of exhaust center of head to end of pipe  31.5"
>>  >>
>>  >>  Test day 98 degrees and about 35%+ humidity
>>  >>
>>  >>  17x12N APC      high 8500rpm low 1600rpm
>>  >>  17x13 std APC   high 8250rpm  low 1500rpm
>>  >>
>>  >>  This is after 5) 16oz tanks of breakin.  I broke it in just like
>>  >>the OS,  alternating rich to lean during first several tanks.
>>  >>
>>  >>  Wayne Galligan
>>  >>
>>  >>
>>  >
>>  >Bob Pastorello, El Reno, OK, USA
>>  >rcaerobob at cox.net
>>  >www.rcaerobats.net
>>  >Just a few notes on my initial test and break-in on this engine.  It
>>  >has not been installed in my plane as of this writing but I cant
>>  >wait.
>>  >
>>  >3M 1.70 stock header
>>  >10 % Magnum fuel
>>  >Bluebird c.f. 2-stroke pipe  24.25" center of head to 1st baffle.
>>  > Total length of exhaust center of head to end of pipe  31.5"
>  > >
>>  >Test day 98 degrees and about 35%+ humidity
>>  >
>>  >17x12N APC      high 8500rpm low 1600rpm
>>  >17x13 std APC   high 8250rpm  low 1500rpm
>>  >
>>  >This is after 5) 16oz tanks of breakin.  I broke it in just like the
>>  >OS,  alternating rich to lean during first several tanks.
>>  >
>>  >Wayne Galligan
>>
>>
>>  --
>>  ___________
>>  Jerry Budd
>>  mailto:jbudd at qnet.com
>>  =====================================
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>>
>
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-- 
___________
Jerry Budd
mailto:jbudd at qnet.com
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