Webra 160 XP - D3 Champs, Thanks

[Jim_Woodward at beaerospace.com]

A quick note before I head to Sydney later today. 

Thank you to Mac H., Emory, Brian, and Cathy for running a superb event 
this weekend.  This was the first time I had met Brian and Cathy and both 
exude class, friendlyness, and a welcoming spirit that will only help to 
bring more pattern flyers into competition.  Emory and Brian also setup up 
flight lines angled to the runway to avoid a devastating sun angle, should 
we have flown in the runways primary direction.  Also, it was great to 
meet everyone in D3 again, and some for the first time like Mike H., team 
Aruba, etc. 

In regards to the Webra 160, the real danger of this engine is that you 
can over lean the entire range of the motor.  If you setup the mixture 
(notice this is not the throttle curve) curve so that you have PERFECT 
zippy throttle response on the ground, you will bake this engine and have 
dead sticks.  Just because you "can" get a perfect zippy throttle response 
on the ground, does not mean it is the best solution for in flight use. In 
fact, just like non-MC carbs, you need to be on the rich side of things to 
be safe, until the engine is broken in and you are entirely familiar with 
its idiosycronsies. 

Emory S. was running a Webra 160, as well as I.  After listening to 
Emory's (both of us standing there), his was noted as running a tad richer 
than mine through the entire range.  He did lean just a few points, but 
was still on the rich side.  Mine is now turning a Mejslik (forgive the 
spelling) 18x10, and the setup in my opinion is the most impressive glow 
setup I've seen.  It is providing a presentation very similar to the 
electrics, and still maintains tons of vertical power/speed after the 
upline snap.  Others can chime in if they like that saw it and they may 
disagree.  This is just my opinion.  This is the ticket for the way I want 
to fly/present the FAI pattern. 
The other setup thing I do is turn the pump screw in 2 turns, then mix out 
with the carb.  The real display of proper setup of the Webra 160 is 
inflight use.  Here are the signs (Jerry B., Dave L. Emory S.,, please add 
too if needed): 
1.  Does the engine idle down during the landing pattern?  Indicative of 
overall lean/rich settings and pipe lengths.  The motor shold idle down 
nicely at any time during the flight. 
2.  During the flight, is there ANY hessitation, gasp for air, silent 
spot, or pop?  If so, the mix points that correspond to the throttle stick 
position are lean (no doubt).  Or you have not enough pump pressure, which 
is why I start out by overpumping the engine and just mixing out. 
3.  This motor does not need to be spitting, slobbering rich on takeoff, 
but untill (everyone that has one) is very familiar with its 
characteristics, please stay on the rich side, and resist the temptation 
to get a perfect zippy response, until you have a number of flights on the 
system. 

Other than that, enjoy not placing your fingers next to a running engine 
for tuning! vbg

Thanks,
Jim W.






"Ed Alt" <Ed_Alt at hotmail.com>
Sent by: discussion-request at nsrca.org
10/11/2004 07:11 AM
Please respond to discussion

 
        To:     "Amram Privat" <amram at leshed.com>, <discussion at nsrca.org>
        cc: 
        Subject:        Re: Webra 160 XP


Amram:
The Webra 1.60 seems to do a poor job of transferring heat to the fins and 

head.  I learned that the Webra 1.60 really needs attention to ducting 
plenty of air to keep the bottom of the engine cool.  I had problems with 
the main bearing loosening up and allowing the crankshaft to shift 
backwards 
enough to cause the prop thrust washer to dig into the crankcase.  This 
happened twice on two almost new engines.  I also had problems with the 
pump 
going flakey, also most likely attributable to excessive heat buildup. The 

other thing is that it is somewhat touchy to adjust.  It runs wonderful 
when 
everything is just right.  However, you get it right for one temperature, 
humidity and field elevation and it completely changes on a different day 
or 
location.  Some change is expected, but you have to really learn what the 
engine wants if you plan to be able to fly it competetively.

Some guys have great luck with the engine.  Locally, one top flyer has 
been 
getting better results after switching to the VP30 pump with his Webra. 
The 
best I can say for it as a competition motor is that it is delicate.  I 
just 
got tired of fussing with the engine all the time, figuring it would be 
better to be able to concentrate on flying instead of being a mechanic all 

the time.

Unless you are already at Webra guru status or have a local Webra guru to 
commiserate with, I would suggest looking into an OS 1.40 RX or OS 1.60 FX 

instead.  Since I could not locate a 1.40 at the time, I dropped the OS 
1.60 
FX  with a VP30 pump in to replace my Webra in mid season and have had no 
problems whatsoever.  I quickly got over the fact that it's side exhaust 
and 
that it is a few ounces heavier.  The wrap around header is no big deal. 
You can get one custom made from Karl Mueller or else you can buy a Hatori 

header.  The Mueller headers are very nice.  You should plan on replacing 
the main bearing with a stainless steel version.  If you stick with the 
Webra, there are now SS bearings available for them too.

BTW, the Webra 1.45 that I owned and flew in the same airplane during the 
frequent 1.60 downtimes never had a problem with the main bearing shifting 

around.  I accumulated about twice as much flight time on the 1.45, but it 

had all the other issues that the 1.60 had, i.e., being touchy, having 
pump 
problems etc.  I hope this helps.

Ed



----- Original Message ----- 
From: "Amram Privat" <amram at leshed.com>
To: <discussion at nsrca.org>
Sent: Monday, October 11, 2004 3:40 AM
Subject: Webra 160 XP


> Hello
> I am about to order the Onyx140 (Protech) and my plan is to use Webra 
160
> XP.
> Any tips ideas or recommendations as to the Webra 160 XP will be highly
> appreciated.
> Thanks
> Amram Leshed.
> http://www.f3a-israel.com
>
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> 
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