Why Air Density Is Important In Engine Tuning.

[Terry Keeley]

Is there a relative ratio/ percentage between a change in air density and the required change in our needle flow? Or is that where the tune it by ear aspect comes into play?

I needed to go about a full point leaner (old school flow meter 7-6) on my 40 boat going from 95-96% here in S. Ont. to Hunsville's 90-91%.

Again I think the humidity throws a third dimension into the mix...

 

[Charles Perdue]

A neat web site to check for weather conditions is: airdensityonline.com/tracks

This site give all of the updated information that you need to adjust for weather conditions. Just find a raceway near the lake where you are running and look it up. Several handy calculators are also included on their site.

This is just one way that I found, I am sure that there are many other places to get the weather information if you do not have a weather meter, airports is one

Charles

 

[timothy johnson]

Thanks Terry for the water grains info and Charles yes I have used that web site and it is very helpful. David, to see some of the runs by Stu Barr , 99MPH with his twin, at the Huntsville race you wouldn't think that was possible with the conditions.. Stu uses a flow gauge and I'm sure he adjusts for the weather. There were some other's that did well with the condition's, but for the most part a lot of people struggled. Thanks to Doug Twaits and Stan Simpson I was able to get some decent finishes with my D hydro.