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Why Apex Seals Fail

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Old 01-16-10, 10:18 AM
  #176  
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Adam, Patman's DIY omp mod.


https://www.rx7club.com/showthread.p...errerid=101407
Old 01-16-10, 05:29 PM
  #177  
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Yeah, I actually made a premix tank for another guy that was on the same GB Trout2 was on for catch tanks. It came out to a little over 1.6 litres.







[img]ttp://www.rx7club.com/attachment.php?attachmentid=372913&stc=1&d=1263684 503[/img]

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Old 10-20-11, 12:43 PM
  #178  
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Interesting read.

Have any of you guys done any testing with cylinder pressure transducers? It really surprises me that I have never seen any cylinder pressure data for a rotary, whereas it is the primary tuning indication used by most engine manufacturers. I will be logging CPX data on my next 20B build, but I have a lot going on lately so that likely won't be until spring.
Old 10-20-11, 03:37 PM
  #179  
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Originally Posted by patman
Have any of you guys done any testing with cylinder pressure transducers? It really surprises me that I have never seen any cylinder pressure data for a rotary, whereas it is the primary tuning indication used by most engine manufacturers


10A engine, 10A engine prototype with trailing plugs only, 10A engine prototype with leading plugs only
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Old 10-20-11, 05:31 PM
  #180  
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Very interesting. Dual plug system is reaching highest combustion pressure and rise itself after ignition is sharpest. Leading only seems poor combination in this example, it has lowest peak pressure and not so much area under the curve where it counts ie early after TDC. Trailing only seems really good, more overall pressure than leading only.

Most interesting for me is blowdown pressure, it seems that leading only has very slow burn rate, pressure is still high in late crank degrees, Trailing and dual system seems better all around - higher peak pressure and lower blowdown - less noise maybe
Old 10-20-11, 09:08 PM
  #181  
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Interesting thread. Learn more and more every day. I have definitely subscribed to this one.
Old 10-20-11, 10:01 PM
  #182  
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Originally Posted by Liborek
Very interesting. Dual plug system is reaching highest combustion pressure and rise itself after ignition is sharpest. Leading only seems poor combination in this example, it has lowest peak pressure and not so much area under the curve where it counts ie early after TDC. Trailing only seems really good, more overall pressure than leading only.

Most interesting for me is blowdown pressure, it seems that leading only has very slow burn rate, pressure is still high in late crank degrees, Trailing and dual system seems better all around - higher peak pressure and lower blowdown - less noise maybe
According to the source document: the leading-only configuration can't propogate to the trailing side easily because it is fighting gas flows as the rotor turns. Thus the combustion is delayed, hence the slow pressure rise. The trailing-only configuration does have a better position in terms of mixture distribution inside the combustion chamber. However it encounters the well-documented flame quenching effects that Mazda has sought to address in later designs.
Old 10-22-11, 07:36 AM
  #183  
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I have been doing some testing with in chamber pressure sensors.....
Attempting to increase burn rate using a combination of best split and advance.
Barry

Old 10-22-11, 07:59 AM
  #184  
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Barry,

do you have a thread on this and if not could you give us additional info. very interesting. what have you learned to date?

wow, new data.

hc
Old 10-22-11, 12:36 PM
  #185  
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very informative thread
Old 10-25-11, 11:31 AM
  #186  
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Does anybody know what the biggest size coolant fitting you can bore into the rotor housing is without weakening it? maybe -10 AN or 3/4 NPT fitting? I found this spec sheet for AN fittings some people might find helpful:

http://assist.daps.dla.mil/docimages...LLLRQMYLYT.PDF
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