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View Full Version : Why does notleistung affect manifold pressure below 100%?



03-27-2004, 11:30 AM
If I understand correctly how MW50-notleistung and C3-einspritznotleistung work, the liquid injection and increased manifold pressure only kicks in when you are above 100% throttle, right?

People have been saying for a long time now that MW50 is not consumed unless you are above 100%. That makes sense. It also follows that "erh√¬∂hte notleistung" (aka C3 injection) does not spray fuel spray into the supercharger unless you are above 100% throttle.

BUT... watching the manifold pressure gauge it you can clearly see that selecting WEP causes higher manifold pressure even at cruise power settings. What the heck is going on here?

03-27-2004, 11:30 AM
If I understand correctly how MW50-notleistung and C3-einspritznotleistung work, the liquid injection and increased manifold pressure only kicks in when you are above 100% throttle, right?

People have been saying for a long time now that MW50 is not consumed unless you are above 100%. That makes sense. It also follows that "erh√¬∂hte notleistung" (aka C3 injection) does not spray fuel spray into the supercharger unless you are above 100% throttle.

BUT... watching the manifold pressure gauge it you can clearly see that selecting WEP causes higher manifold pressure even at cruise power settings. What the heck is going on here?

Heavy_Weather
03-27-2004, 11:38 AM
i would think its the injection of the methenol to the fuel mixture that causes the increase. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif

"The wise man is often the man who plays dumb."

03-27-2004, 11:46 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Heavy_Weather:
i would think its the injection of the methenol to the fuel mixture that causes the increase. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-wink.gif<HR></BLOCKQUOTE>

Guhh, no. Stop being a wiseguy http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif I'm looking for real answers.

Fillmore
03-27-2004, 12:59 PM
My testing has shown that the C3 injection does increase performance at throttle settings less than 100. MW50 does not increase performance at throttle setting below 100, but it does increase engine temperature i.e. you will run hotter with MW50 below 100%, but won't have any more power. This testing was done awhile ago, in 1.11 if I remember correctly.

ZG77_Lignite
03-27-2004, 01:01 PM
I'm going to put in an opinion Cosmocart, mostly because I'm not sure if anybody else will (hopefully a technician will expound on this and teach us something).

However, regarding the methanol or fuel injections, as I understand it these 'devices' were turned on by the pilot. When turned on, this 'opened up' the throttle system by allowing more air passage (increased airflow or higher manifold pressure/suction). However, this new higher manifold pressure was more dangerous for the engine (of course), so an additional device also turned on when (and only when, apparently) the higher manifold pressures were reached; this being MW-50 or direct C3 injection. MW-50 or C3 injection don't increase manifold pressure in and of themselves, they are there to protect (increase cooling, reduce detonation) the engine while operating at these higher pressures.

So, assuming the above is true, imho it is likely that manifold pressure would increase at all power settings, less so at lower power settings, which is similar to what we have in FB.

I believe GM-1 system is different, injecting nitrous oxide, which DOES increase combustion/manifold pressure/horsepower directly, I'm unfamiliar with the how GM-1 operates in FB, but I belive it is attempted to model this through altitude limitations and such.

I realize the FB system is not a perfect representation, manifold pressure is a complex thing, and there are many aspects of it that are missing in FB, however, it seems reasonably realistic to me (meaning more realistic than most, if not all, flight sims before).

Heavy_Weather
04-04-2004, 11:51 AM
basically, this is what i said, just a little more defined http://ubbxforums.ubi.com/images/smiley/52.gif

"The wise man is often the man who plays dumb."