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 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)

Views: 327

Reply to This

Replies to This Discussion

  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

Hi Bruce,
I would like to know i this Carb Heat trick helps you?
let us know next time you fly.

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.
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)


New from Zenith:

Zenith Planes For Sale 

Classified listing for buying or selling your Zenith building or flying related stuff...

Custom Instrument Panels
for your Zenith

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, power distribution panel, Approach Fast Stack harnesses, Dynon and Garmin avionics, and more.

Custom Upholstery Kits for your Zenith Aircraft:

Zenith Vinyl Upholstery Kits

Zenith Apparel from EAA:

Zenair Floats

Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz

Builder & Pilot Supplies:

How to videos from

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit for the latest DVD titles.

Aircraft Insurance:


West Coast USA:

Pro Builder Assistance:


Transition training:

Golden Eagle Aviation

Pianosa Flying Farm

Aircraft Spruce & Specialty for all your building and pilot supplies!

© 2021   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service