Manifold Pressure Adjustment Chart (Intercooler Differential)

[Cpt_Kirk]

Can someone aid me in understanding this chart correctly?

Id post pictures but i cant on this phone. Theyll upload but i cant "close this window."

Anyhow, for those familiar, do the calculated values indicate how much more pressure is inside the manifold based on the in/out temp difference from the intercooler?

 

[RussR]

In the one I am familiar with, that installed on a Piper Turbo Saratoga, the value from the chart is how much you subtract from book value when you set the actual power.

So if the book says use 28" for some power setting, and you have a 30 deg differential, and from the chart for that MP setting and differential you get a 2.0 adjustment, then you really set 26" to make the same power as the book value. This is because the cooler, denser air from the intercooler makes more power than it would otherwise, so to maintain the same percent power, you need to set the throttle a little lower.

Is that what you're asking?

 

[Cpt_Kirk]

Thats exactly what i was asking, Russ. I just needed someone else to confirm it for me. Thanks for all of your help now, and in the past!

Edit: The chart was referring to a TC Saratoga in my case. I couldnt find anything about it on the manufacturers website.

 

[Cpt_Kirk]

Here is the chart.

 

[Cpt_Kirk]

Intercooler Temp In (engine off)

 

[Cpt_Kirk]

Intercooler Temp Differential (engine off)

 

[Cpt_Kirk]

Intercooler Temp Out (engine off)

 

[Sac Arrow]

My Turbo Arrow was intercooled, but the STC included a new power chart which was adjusted downward for the intercooler, vs, an offset chart.

 

[RussR]

That appears to be an identical installation to the one I mentioned. Just leave it on "differential", the actual numbers aren't really useful. With the engine off, it should of course say "0", but I suppose the placement of the probes could cause that if the plane was in the sun, etc.