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  #41  
Old 10-03-2015, 08:55 AM
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carrollcw carrollcw is offline
 
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Location: Friendswood, TX
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Here are some numbers from 2 recent flights:

11,500'
167 TAS
20" MP
6.3 GPH
1/3 110 LOP
2/4 35 LOP

7,500'
168 TAS
23.4" MP
7.3 GPH
1/3 170 LOP
2/4 80 LOP

So, as you can see, I can even go to almost 200 LOP and still have a smooth running engine!
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #42  
Old 10-03-2015, 09:42 AM
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DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
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Quote:
Originally Posted by carrollcw View Post
Here are some numbers from 2 recent flights:

11,500'
167 TAS
20" MP
6.3 GPH
1/3 110 LOP
2/4 35 LOP

7,500'
168 TAS
23.4" MP
7.3 GPH
1/3 170 LOP
2/4 80 LOP

So, as you can see, I can even go to almost 200 LOP and still have a smooth running engine!
Here's a larger engine, with well-worn Slicks and an AFP FM200, at 25~30 LOP, going 10 knots faster on 7.8 gph. I'll be going to electronic ignition in the near future, and expect to pick up the half gallon due to timing advance.

No magic.

Note the GAMI spread...5 degrees F. Given an engine with less than perfect mass airflow balance, an engine with each cylinder's fuel delivery matched to the available air works better than an engine with some cylinders running a little rich or lean.

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RV-8 SS
Barrett IO-390

Last edited by DanH : 10-03-2015 at 09:51 AM.
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  #43  
Old 10-03-2015, 09:52 AM
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RVbySDI RVbySDI is offline
 
Join Date: May 2005
Location: Tuttle, Oklahoma
Posts: 2,563
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Quote:
Originally Posted by carrollcw View Post
. . . For those of you considering a Titan engine, just be wary of the updraft sump. I have heard the Titan horizontal cold air sump has much better airflow. However you pay the price of higher oil temps. Living in Houston, I knew I would have oil temp probs with a high horsepower engine, so I elected to go with the vertical induction. So, since I have chosen to stick with vertical imduction, I just need to find a sump with more balanced air flow. Seems the superior sump is the way to go.
I have not heard anyone say the forwared facing cold air induction would result in higher oil temps before your post. I have just such a sump feeding air into my Titan IO340. I have absolutely no oil temp issues in the 5+ years I have been flying this setup. In fact it is the reverse of what you say. I sometimes think my oil temp should be higher than it usually is. Typically my oil temp is around 175 F or so. Even on blistering hot days, of which Oklahoma has been known to have, it may reach 195 F. I would not let this unsubstantiated notion stop you from installing cold air induction. I do not believe it is an accurate statement based upon my first hand experience running it in my plane.
Quote:
Originally Posted by carrollcw View Post
Here are some numbers from 2 recent flights:

11,500'
167 TAS
20" MP
6.3 GPH
1/3 110 LOP
2/4 35 LOP

7,500'
168 TAS
23.4" MP
7.3 GPH
1/3 170 LOP
2/4 80 LOP

So, as you can see, I can even go to almost 200 LOP and still have a smooth running engine!
reality is, it doesn't really matter whether you run 10, 50, 100, 200 LOP. Those EGT readings are not anywhere as important as fuel flow, and even more so CHT readings, when it comes to running succsessfully LOP. Monitoring EGT gets you in the LOP range, then your fuel flow and CHT are what you need to watch to keep things where you want them after the initial Big *** Pull to LOP.
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RV9A
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Last edited by RVbySDI : 10-03-2015 at 10:22 AM.
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  #44  
Old 10-03-2015, 10:15 AM
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RVbySDI RVbySDI is offline
 
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Location: Tuttle, Oklahoma
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Dan,
You posted just before my previous post. Alhough Dan has an 8 with a larger engine than my 9A the engine performance is very similar. He just flies faster than I do with the same LOP operations. Although to be fair, in this example I am at 12.5K and burning 6.7 gph. I would get a touch closer to his speeds if I were to bump my fuel flow up to the 7.8 gph he was running in his example. But speed isn't the thing to observe in either pic. Look at both Dan and my Oil and CHT temperatures.
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Last edited by RVbySDI : 10-03-2015 at 10:21 AM.
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  #45  
Old 10-03-2015, 10:38 AM
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skylor skylor is offline
 
Join Date: Aug 2009
Location: Southern California
Posts: 882
Default Temps

Quote:
Originally Posted by RVbySDI View Post
Dan,
You posted just before my previous post. Alhough Dan has an 8 with a larger engine than my 9A the engine performance is very similar. He just flies faster than I do with the same LOP operations. Although to be fair, in this example I am at 12.5K and burning 6.7 gph. I would get a touch closer to his speeds if I were to bump my fuel flow up to the 7.8 gph he was running in his example. But speed isn't the thing to observe in either pic. Look at both Dan and my Oil and CHT temperatures.
Down low, high MAP LOP ops. Also note the engine and oil temps (67 OAT).





Skylor
RV-8
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  #46  
Old 10-03-2015, 11:16 AM
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carrollcw carrollcw is offline
 
Join Date: Jan 2012
Location: Friendswood, TX
Posts: 193
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Quote:
Originally Posted by RVbySDI View Post
I have not heard anyone say the forwared facing cold air induction would result in higher oil temps before your post. I have just such a sump feeding air into my Titan IO340. I have absolutely no oil temp issues in the 5+ years I have been flying this setup. In fact it is the reverse of what you say. I sometimes think my oil temp should be higher than it usually is. Typically my oil temp is around 175 F or so. Even on blistering hot days, of which Oklahoma has been known to have, it may reach 195 F. I would not let this unsubstantiated notion stop you from installing cold air induction. I do not believe it is an accurate statement based upon my first hand experience running it in my plane.
Cold air induction does in fact increase oil temps. I spoke with Kevin Eldridge when he was at Titan, Clint at Veterman's exhaust, as numerous others with a lot of engine knowledge. You may not have an issue, but that is most likely due to the lower HP of an IO340. More HP = more heat. The RV7 cowl was never designed to handle the cooling issues of higher HP engines. Once you go past 180 HP, you will have oil temp probs with the standard setup.
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #47  
Old 10-03-2015, 10:04 PM
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RVbySDI RVbySDI is offline
 
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Location: Tuttle, Oklahoma
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Quote:
Originally Posted by carrollcw View Post
Cold air induction does in fact increase oil temps. I spoke with Kevin Eldridge when he was at Titan, Clint at Veterman's exhaust, as numerous others with a lot of engine knowledge. You may not have an issue, but that is most likely due to the lower HP of an IO340. More HP = more heat. The RV7 cowl was never designed to handle the cooling issues of higher HP engines. Once you go past 180 HP, you will have oil temp probs with the standard setup.
just so you are aware of one other data point, my IO-340 is rated by ECI at 185 HP. So according to their information I have a 180+ HP engine. Also, not sure what you refer to as a "standard setup". I have a standard Vans IO-360 RV-7 cowl with the Vans RV-7 snorkel on my 185 HP IO-340. So this engine is not as powerful as Dan's IO-390 but I would put it up against any 360 out there.
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  #48  
Old 10-03-2015, 10:44 PM
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skylor skylor is offline
 
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Location: Southern California
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Quote:
Originally Posted by carrollcw View Post
Cold air induction does in fact increase oil temps. I spoke with Kevin Eldridge when he was at Titan, Clint at Veterman's exhaust, as numerous others with a lot of engine knowledge. You may not have an issue, but that is most likely due to the lower HP of an IO340. More HP = more heat. The RV7 cowl was never designed to handle the cooling issues of higher HP engines. Once you go past 180 HP, you will have oil temp probs with the standard setup.
Just to be clear, be sure that you aren't misunderstanding "cold air induction" as the cause of higher oil temperatures vs. engines with oil squirter nozzles. It just so happens that the common 4 cylinder lycomings that have the forward facing induction are the angle valve engines (IO-360A) that also include piston squirter nozzles. The piston squirters are often attributed to increased oil temperatures since the oil is being used to remove some of the combustion heat from the pistons.

Skylor
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  #49  
Old 10-04-2015, 09:26 AM
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carrollcw carrollcw is offline
 
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Posts: 193
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Not confusing the 2.
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RV-7 Flying Since March 2015
N412HC
Titan IOX-370
SDS Tunable Injectors
EFII Dual Ignition and Fuel Injection
Garmin G3X Touch
Whirl Wind 200RV Prop
7XS0 Polly Ranch Airpark, Friendswood, TX
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  #50  
Old 10-26-2015, 06:41 PM
Don at Airflow Don at Airflow is offline
 
Join Date: Jun 2006
Posts: 316
Default Another data point. Up draft sump, not to bad.

Here is another data point.

We are currently developing a fuel injection kit that will fit in the stock Van?s 320 cowling without modifying the cowling. Our test bed was an RV-6 with a Titan 340 engine. The stock configuration was with an MA-4 carburetor (although the sump looked like a stock 360 sump to me). Data from the GRT down load on previous runs with the carb. gave the following:
T.O. power of 2624 RPM and 29?MAP around 15 GPH with EGT?s of 1445, 1411, 1265, 1223 (cyls. 1-4 respectively in degrees F.). At a cruise power setting of 2600 and 24?and 11.3 GPH with EGT?s at 1215, 1213, 1318, 1305. All data here was full rich

With no changes to the engine other than bolting on a FM-150L with stock injector nozzles we install on a 320 (all the same size) and installing the necessary high pressure engine driven pump, aux pump and a new inlet filter air box we got the following. Take off power 2600 RPM and 28.5? MAP fuel flow was 15.7 GPH with EGT?s at 1274, 1294, 1251, 1298. Cruise power of 2400 and 24? fuel flow 11.4 GPH with EGT?s at 1225, 1268, 1217, 1249. Again all data here was full rich

Checking the full rich to peak EGT at 24 square gave a change of around 230 degrees F. Indicating the fuel control was set plenty rich. This gives a F/A of around .089 (or for you car guys 11.2:1). A quick lean to peak curve was run at 24 square to check the GAMI spread. This was by no means really accurate because the time to lean was only around 45 seconds( normally to get accurate data, EGT needs to sit on a data point for 30 seconds then lean 0.2 GPH etc.), but GAMI spread was 0.3 to 0.1 GPH. This was only run to 50 degrees LOP with smooth operation.

While we are still improving our filter box to get rid of some flow loses this preliminary data shows that the stock up draft sump that many think is the evil for air distribution, really flows air quite well. Can there be improvements; probably. But the gains probably won?t be noticeable in a flight situation. Even with tuning the injector nozzles we probably will not see an improvement in power, with only a slight improvement in fuel economy.

This was a pretty simple install, no programming, no jet changes, just straight up bolt on and set the idle mixture.

So, more to come as we complete this project with the final design of the air box and gather additional real flight data.

Don
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