Using Carb Heat as a mixture control

For what it's worth...I was curious if anyone else has discovered that you can use the carb heat to cool your EGTs and CHT?

My Jab 3300 works great. I was able to dial my motor in during the Phase I flight testing. Jetting and baffles are important, but the single biggest discovery was the use of Carb heat to affect the mixture.

Applying Carb Heat has the effect of thinning the density of the intake air. Soooo, applying partial carb heat during any phase of flight has the same effect as richening the mixture (as in...extra fuel for cooling!)

Although it seems counter intuitive to apply heat to an already hot engine....you will find it works quite nicely. As long as you don't apply too much and make the engine stumble, you can even do this during high power situations like climb and cruise.

I have a Dynon D180 and monitor all 6 EGT's and CHT's I can consistently keep everything in the green even on the hottest days (Of course I live in North Carolina, so that may not impress everybody)

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Permalink Reply by Bruce crum on April 3, 2015 at 6:46am

  Wesley I also have the jab 3300 what have you done as far as extra baffling and jetting .  I have been fighting over heating problems since day one.    Bruce

Permalink Reply by Wesley Parker on April 3, 2015 at 9:24pm
Hi Bruce,
I would like to know i this Carb Heat trick helps you?
let us know next time you fly.

Wes
Permalink Reply by Christopher Nail on April 3, 2015 at 7:25am
I was taught this trick during transition training and it works quite well. It's never a cht issue, but usimg that carb heart will bring the egts down significantly.
Permalink Reply by Wesley Parker on April 3, 2015 at 9:27am
In my case it will bring down CHT after 30 seconds or so.
EGT is almost instant, and CHT lags a bit. (more mass to change temp)

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