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  #21  
Old 01-14-2018, 09:05 PM
Aircraft Specialty Aircraft Specialty is offline
 
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Location: Oconomowoc, WI
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Originally Posted by Aircraft Specialty View Post
We updated our website to show more information about the PMAG setup for the RV-14 and RV-14A both in the single and dual configuration.

The info is located on the RV-14 Products page.

http://aircraftspecialty.com/rv-14.html

Here is a link directly to the Firewall forward information manual.

http://www.aircraftspecialty.com/PDF...RV-14%20FF.pdf

As always, we are happy to answer any questions or build custom sizes for different configurations.

Have a great weekend and happy building!

This document has been updated to show the PMAG configuration adel clamp securing as well as the rubber PMAG hoses. In addition, we have now included the FM-150 servo configurations.

The single pmag pictures are not yet available, but the package will be nearly identical, except that one of the rubber hose fittings will instead include an AN-cap to plug the port. This will allow an easy change to a dual PMAG configuration down the road if desired.

http://www.aircraftspecialty.com/PDF...RV-14%20FF.pdf

Happy Building
Steve
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Aircraft Specialty is Your Source for Custom CNC parts, CNC cut instrument panels and labeling, Teflon fuel/oil hoses, Headsets, and many other items for Experimental Aircraft.

aircraftspecialty@gmail.com

www.aircraftspecialty.com
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  #22  
Old 01-15-2018, 11:04 AM
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N941WR N941WR is offline
 
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Location: SC
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Quote:
Originally Posted by KeithB View Post
I have a Superior XP-400 with dual P-mags. I installed the jumper (less advance) to help keep temps under control during break-in. After about 30 hours when it was clear I did not have CHT issues, I removed the jumper for max advance. The engine provides great performance, excellent CHTs,and runs very well lean-of-peak with very nice efficiency. I’m curious why do you say this advanced timing is way too much for an angle valve engine?
That is not a good setting for your engine and you could be giving up some power, and risk damaging your engine.

What is the recommended timing for your engine? I belive it and the IO-360 & 390 angle valve engines are designed for 20° BTC timing settings.

The "Jumper In" A configuration starts at 26.6° and the "No Jumper" configuration starts at 30.8° BTC for high power operations, such as takeoffs and they advance from there.

With parallel valve engines, we have been able to demonstrate better performance and cooler CHT's with slightly reduced advance settings.

I suspect you will pick up some performance and reduced fuel burn, if you customized your timing configuration close to the recommended 20° BTC.

I will be happy to work with you (or anyone else with an Angle Valve engine), to prove this out. Just PM your number, if you are interested.
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Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html

Last edited by N941WR : 01-15-2018 at 11:08 AM.
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  #23  
Old 01-16-2018, 08:08 AM
KeithB KeithB is offline
 
Join Date: Mar 2014
Location: Granbury, TX
Posts: 162
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Hi Bill:

This thread prompted me to do some digging on VAF. Last evening I invested an hour in an 18 page thread on the topic from 2013/14 (one you participated in). With this background, I am now intrigued enough to do some more experimentation and evaluation.

During break-in, I used the A curve with manifold pressure disconnected for the first few hours. When I didn't see a single CHT over 400° despite the high power settings, I connected the manifold pressure and after more hours, switched to the B curve. During my break-in, I was adding wheel fairings piece by piece so performance changes were impossible to attribute.

With 180 hours, I now get 170 kts TAS at 7,500 on 8.2-8.3 GPH, CHTs in the low 300s and never over 400 no matter what - quite a bit better than I saw on my RV6 and much better than I expected on this larger airplane, so I am (was?) quite happy. However, after reading all the discussion (older thread) I will give the A curve a serious evaluation now. Unfortunately, tomorrow the airplane goes into the paint shop so my testing will have to wait. I will contact you in about a month.
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RV-14A Builder - kit #136
N314KC - First flight Mar 8, 2017, >300 hrs
RV-6A sold
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  #24  
Old 01-16-2018, 11:49 AM
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N941WR N941WR is offline
 
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Keith,
Here is the good news, you will not hurt your engine by moving the timing down to 20°, where it belongs. Running more advance can cause damage.

Check your PM's.
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Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html
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  #25  
Old 01-16-2018, 01:33 PM
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Robertc Robertc is offline
 
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Location: Omaha, NE
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As info I have a TMX360 8.5 comp. ratio. Originally 113 eMag/pMag on my RV7. An early issue with the pMag resulted in a circuit board change. Last annual I sent them in for maintenance & upgraded the eMag to PMag. The circuit board on that unit wasn’t upgradable to the latest software. I decided to remove the jumpers & time them both 2 teeth after TDC. (149 tooth ring gear) This appears to work well & starting is really smooth. It appears to be 1 or 2 knots faster LOP @ 8gph & 8500ft.
Bob
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  #26  
Old 01-16-2018, 04:40 PM
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N941WR N941WR is offline
 
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Quote:
Originally Posted by Robertc View Post
As info I have a TMX360 8.5 comp. ratio. Originally 113 eMag/pMag on my RV7. An early issue with the pMag resulted in a circuit board change. Last annual I sent them in for maintenance & upgraded the eMag to PMag. The circuit board on that unit wasn’t upgradable to the latest software. I decided to remove the jumpers & time them both 2 teeth after TDC. (149 tooth ring gear) This appears to work well & starting is really smooth. It appears to be 1 or 2 knots faster LOP @ 8gph & 8500ft.
Bob
Bob, you are still running too much advance.
The B curve (They are the same on both boards) starts at 30.8. So by timing them two teeth after TDC, you are essentially running 26* timing, just a little less than the A Configuration.

However, the 114 P-mags (and your 113's with the 114 boards) fires the plugs at 4 degrees after TDC for starting (whenever below 200 RPM). This means you are at risk of a kickback with your setup.

It is best for you to put the jumper in and set the P-mags at TDC. (Assuming your TMX360 is a parallel valve O-360, 8.5:1 is the standard compression, it is even better to reduce the A configuration setting by 1.4 degrees.)
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Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html
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  #27  
Old 01-16-2018, 05:46 PM
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Robertc Robertc is offline
 
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Location: Omaha, NE
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This confuses me a little. Before the upgrade I would get an occasional kickback when timed with the jumper at TDC or even a half tooth retarded. Once I realized I needed 4 deg. retard at start I figured I’d just remove the jumper & set the retard by 2 teeth for 4deg on the older board & 8deg on the newer. I figured this would get me a running curve that’s retarded a little from the A curve on both. The start is really nice and spins up off the starter in 3 or 4 hits kind of like a rough running turbine. It seemed to make sense which is why I posted. ? Bob
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  #28  
Old 01-16-2018, 06:55 PM
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N941WR N941WR is offline
 
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There are a couple of things that can cause a kick back, including too much fuel when priming the engine.

The older software, pre-version 40, would fire the plugs at TDC when starting. It wasn't until V40 came out that they started firing the plugs at 4 degrees after TDC when below 200 RPM.

You might be firing just after TDC, as the resolution for setting the timing on the flywheel really isn't that great.

It is my recommendation to program the P-mags and set them to TDC. If you go this route, document the timing setting in your engine log book so you know exactly what they are. That way, if you ever send the P-mags back in for a checkup they will come back reset to factory defaults. Then you can reset them to your desired configuration.

Programming them is easy enough to do with the free EICAD program from EMAG; however, it will require you to buy a USB to Serial converter.

That you can rip down here to SC86 and we can do it here. All you will have to do is remove the cowls. (We are a bit far from Nebraska though.)
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Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html
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  #29  
Old 01-16-2018, 06:58 PM
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N941WR N941WR is offline
 
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Robert,

Check your PM's.
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Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html
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