Do You Use Ram Air Poll

[201er]

I was surprised to learn that a bunch of guys have never even once opened their ram air. So I wonder what proportion of Mooney pilots use the ram air or not and their reasonining. Be sure to state what kind of Mooney in discussion and how much impact the ram air has.

[Ron McBride]

In my 69F I use it at altitude, above 5000. I get a full inch out of it.

Ron

[smccray]

I've opened the ram air at altitude but doesn't seem to make any difference.  If there is a difference I don't see it on the MP gauge.

[aerobat95]

Quote: N9154V

In my 69F I use it at altitude, above 5000. I get a full inch out of it.

Ron

[Immelman]

My understanding is that the J's induction system was well-designed enough that it didn't matter. The E's and F's on the other hand... it makes a substantial difference. If the air is clean and I'm not going through visible moisture the ram air is coming on with my after-takeoff checklist and staying on until I start backing the power back in descent.

[flight2000]

I use it above 5,000 feet in clean air.  I usually see about an inch increase in Manifold pressure as well. 

Brian

[Vref]

Nope, disabled and covered on my J

last one should be My mooney doesn't have it anymore...

[Shadrach]

I use it whenever in clean air. Down low I get >1" of mp in my 67 F. If I'm LOP, opening the ram air will actually drop EGTs ~20df when below 5000ft.

[Ned Gravel]

Quote: flight2000

I use it above 5,000 feet in clean air.  I usually see about an inch increase in Manifold pressure as well. 

Brian

[jax88]

I have opened it a handful of times above 10,000ft, but I only notice just less than an inch of manifold pressure increase.

[Shadrach]

Quote: jax88

I have opened it a handful of times above 10,000ft, but I only notice just less than an inch of manifold pressure increase.

[Piloto]

On the M20J models the only time you will see some significant difference (1/2") is when your IAS is above 140kts. So above 10,000 ft is hard to see any difference. The RAM air differential pressure is in direct proportion to your indicated airspeed. Any significant advantage would be below 5,000 ft at full throttle.

José

[BlueSkyTraveler]

In my '67 F model i use it above seven grand ---- or higher if i still get bug splatter on the windshield up at 7,000------ what are those insects doing that high anyway???? Does anyone else consider that or just go for it?????

[Bennett]

I have the LoPresti cowl on my M20J, and I regulary use the ram air above 5000' when the air looks clean.  I get between .8 and 1.0 " increase in MP with the ram air fully open.  The LoPresti ram air is quite different from the stock cowling. You can see this on their website and video.  Nice cowl, but expensive.

[drapo]

Quote: edgargravel

Me too.  On an E model.

[KSMooniac]

It was next-to-worthless on my J, and I removed the system.  (there is a thread on the Misc board about this right now).

[Shadrach]

Quote: Bennett

I have the LoPresti cowl on my M20J, and I regulary use the ram air above 5000' when the air looks clean.  I get between .8 and 1.0 " increase in MP with the ram air fully open.  The LoPresti ram air is quite different from the stock cowling. You can see this on their website and video.  Nice cowl, but expensive.

[jetdriven]

the J is too, the inlet for the ram air goes straight through the fuel injector servo.  the reason I heard there is not much MP gain with ram air on the J is the induction plenum is much more efficient, IE, less "loss" in the duct.

[meddesign]

yes at altitude at full throttle 7.5k or higher pick up an inch MP

[DrBill]

Yes over 4000. When I remember it.

65 E

BILL

 

[Shadrach]

Quote: jetdriven

the J is too, the inlet for the ram air goes straight through the fuel injector servo.  the reason I heard there is not much MP gain with ram air on the J is the induction plenum is much more efficient, IE, less "loss" in the duct.

[jetdriven]

I have seen 29" perhaps 29.5" of MP at 1000' before. the altimeter setting was 30.25.   I'd like to see as well.

[201er]

Meanwhile the 201 POH claims greater than ambient pressure at various altitudes under standard conditions!

[M016576]

I use ram air in my J more as an indicator for when to clean out my air filter or replace the element.  Any gains over .4 or so at altitude and I know it's dirty....  

[DaV8or]

I used to use mine all the time, but have stopped because of concern for my induction boot. It's a glued up repaired one and my theory is that air going through the filter is easier on it. As soon as Mooney, or anyone else gets around to making me a new one, I'll go back to using it again above about 5k feet. It does help.

I love the Lo Presti cowl and really like the ram air valve they use. Wish I could just get the valve and retrofit my SWTA cowl with it... or Lo Presti just reasonably price their cowl kit.