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  #11  
Old 11-12-2014, 09:57 AM
LifeofReiley's Avatar
LifeofReiley LifeofReiley is offline
 
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Location: Round Rock, TX
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Default

The insert referred to in the SB mounts inside the sump. Google SB-258 and you can find the drawing. It pertains to OLD lycomings only.
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  #12  
Old 11-12-2014, 04:04 PM
A2022 A2022 is offline
 
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Posts: 2,425
Default from 9-12-13

I had a local guy at HAO make a sump riser (SB258) for my Superior O-320 because I had a rough engine and high rear cylinder head temps (400F) on my two flights that I was not satisfied with. My front cylinders were 325F. I added a lip to the sump riser insert to account for the throttle bracket and gasket offset to minimize abrupt steps in the riser from the carb. I also polished some flash from the carb vanes. I will have MT prop gov SB (prop surging issue), gear fairings and wheel pants and D100 software update, and sump riser for the next flight. I'll report on engine response. I have a copy of SB258 I can send you. Note: I followed Bob's idea and purchased the thick walled alum tubing from England to make the riser.

http://www.vansairforce.com/communit...+insert&page=2

Superior uses the same sump for both 320 and 360. This sump has a taper at the opening that creates a step at the 320 carb that causes the rear cylinders fuel distribution issue. Superior will tell you that it doesn't matter, but it does. You need the sump riser insert. I pro-sealed my custom insert in place rather than drilling an anti-rotation pin into the sump wall. After a year upon inspection (200 hrs) it is solid. CHT and EGT are even across all cylinders with the sump riser.


Last edited by A2022 : 11-13-2014 at 03:42 PM.
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  #13  
Old 11-12-2014, 04:49 PM
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
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Quote:
Originally Posted by Dbro172 View Post
I will have to lean it out and check to respond to your question but I think it has more to do with the butterfly valve setting. I can check fuel flow at wot and 65% power but that will pry mean climbing to 12500 da or so?

I think if you look at the charts 75% (or less) would be reached with WOT - and leaned to Rupsters range of fuel flow. esp at 9500 ft. This way you avoid that throttle position.

I think I'm realizing some significant ram air horsepower or some significant horsepower increase from the ASA vacuum valve because whereas I only get 2150 rpm static at 1500 msl, I can still wind it up to 2750 at 10,000 DA.

Neither is affecting your RPM. You have a fixed pitch, so with the incoming airspeed the balance RPM match of prop demand and engine power increases. Like full power and going into a dive, RPM will increase.
I added the colored responses above.
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  #14  
Old 11-12-2014, 06:45 PM
A2022 A2022 is offline
 
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Default throttle bolt

Quote:
Originally Posted by LifeofReiley View Post
Yes... and mounted inside the bottom of the sump. You have a Superior Engine, not going to be your issue.
side issue: you may think about reversing the orientation of the throttle cable bolt to reduce fatigue in the threads.

Last edited by A2022 : 11-12-2014 at 06:49 PM.
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  #15  
Old 11-12-2014, 06:54 PM
cajunwings cajunwings is offline
 
Join Date: Jun 2007
Location: new iberia la
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Default sump riser

Does anybody have a photo of the insert before installation?

Don Broussard

RV 9 Rebuild in Progress
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  #16  
Old 11-12-2014, 07:16 PM
A2022 A2022 is offline
 
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Default sketch

I made mine to this sketch because I wanted no gaps between the riser and carb. I let it cure in place with proseal. Also, I think you can still buy the Lycoming sump riser insert listed in SB258. I still have about of foot of tubing from England that is the correct ID.


Last edited by A2022 : 11-13-2014 at 04:50 AM.
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  #17  
Old 11-13-2014, 08:55 AM
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LifeofReiley LifeofReiley is offline
 
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Quote:
Originally Posted by Steve Melton View Post
side issue: you may think about reversing the orientation of the throttle cable bolt to reduce fatigue in the threads.
Derek... +1 what Steve said with the bolt. If this SB is a fix for a Superior issue that's awesome. Sounds like it works.
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  #18  
Old 11-13-2014, 09:17 AM
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Dbro172 Dbro172 is offline
 
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Per Aerosport my superior O-320 has an 0-320 sump and therefore i dont believe this spacer will help me any.

Edit: this proved to be wrong later down the road when I researched further and removed the carb... Deffinately a difference in diameter from my ma4spa carb to the opening in the bottom of the sump. About a 3/16" step wider from carb to sump
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RV-9A #92103 - N803DK
G3X, Superior XO-320, Dual Pmags, Catto 3B
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1974 Bellanca Super Viking - N16AW - Flying
RV-8 #83565 - N184DK - building
1968 Mooney M20C - N6801N - Sold
1956 C-182 - N744W - Sold

Last edited by Dbro172 : 03-14-2015 at 01:00 PM.
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  #19  
Old 03-14-2015, 01:01 PM
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Dbro172 Dbro172 is offline
 
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Default Follow up to this issue - solved

I finally made major breakthrough in my issue with split EGTs and uneven fuel distribution between the front and rear cylinders. Aerosport fabricated me an insert, similar to applicable service bulletin, SB 258 dating back to the 50's, that smoothes out the transition from my ma4spa carb to the O-360 sump. First test flight showed way more even EGTs leaned out in cruise as well as smoother operation at higher power and ability to lean better. Can't wait to get up high and stretch the legs on it now. This eliminates the step in varying diameters from the carb to the sump, which must have been disturbing the airflow.



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Derek Hoeschen
EAA Tech Counselor
RV-9A #92103 - N803DK
G3X, Superior XO-320, Dual Pmags, Catto 3B
www.mykitlog.com/dbro172/

1974 Bellanca Super Viking - N16AW - Flying
RV-8 #83565 - N184DK - building
1968 Mooney M20C - N6801N - Sold
1956 C-182 - N744W - Sold
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  #20  
Old 03-14-2015, 01:37 PM
alpinelakespilot2000 alpinelakespilot2000 is offline
 
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Quote:
Originally Posted by Dbro172 View Post
I finally made major breakthrough in my issue with split EGTs and uneven fuel distribution between the front and rear cylinders. Aerosport fabricated me an insert, similar to applicable service bulletin, SB 258 dating back to the 50's, that smoothes out the transition from my ma4spa carb to the O-360 sump. First test flight showed way more even EGTs leaned out in cruise as well as smoother operation at higher power and ability to lean better. Can't wait to get up high and stretch the legs on it now. This eliminates the step in varying diameters from the carb to the sump, which must have been disturbing the airflow.



Thanks for posting this Derek. This is exciting! I have an aerosport 0-320 that has very dramatic differences in front vs rear CHTS depending on whether I'm WOT or pulled back a bit. Does this sound like you? Any suggestions about how to approach aerosport with this (e.g. Any specific tests/numbers they wanted?).

Also, given the thickness of the riser, did it mess with your snorkel/FAB alignment?
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