New to the forum and first post. Recently did a Stage 1 upgrade on 2011 Street Glide 103. V and H all the way back, Kuryakyn hyperchager and a DynoJet Power Vision. I love the Power Vision although I couldn't find a map that got me to an AFR target of 13.7. So I modified the map to 13.7 from 14.1. Bike runs noticeably cooler and I have better low end power.

Just curious...what is everyone else using? Am I to far off going from 14.1 to 13.7 ?

Cheers guys!

 

I believe 14.7 to 1 has been standard since day one. This is weight by the way - if you were using pounds it would read 14.7 pounds of sea level air to 1 pound of fuel, and that would give you a completely clean burn with no fuel or oxygen residue left over. So, less weight of air will give you a richer mixture with more cooling effect due to unburnt fuel leaving the exhaust. You seem to be happy with what you have so I'd try for awhile and see how it goes.

 

Isn't 14.7 the standard set by the epa for their emissions crap? Which in reality is too lean.

 

did you just change all the afr in all cells to 13.7? or did you target any ranges?

you should read this thread: https://www.hdforums.com/forum/ignit...-by-admin.html

its a giant thread, and there have been many changes with the pv, so maybe start at the newest end and maybe go back 6-8 months?

 

Skratch - that's exactly what I did. I changed all the 14.1 to 13.7, saved it, and uploaded to the PV1.

 

The stoichiometric mixture for a gasoline engine is the ideal ratio of air to fuel that burns all fuel with no excess air. For gasoline fuel, the stoichiometric air–fuel mixture is about 15:1[1] i.e. for every one gram of fuel, 15 grams of air are required. The fuel oxidation reaction is:
Any mixture less than ~15 to 1 is considered a rich mixture; any more than ~15 to 1 is a lean mixture – given perfect (ideal) "test" fuel (gasoline consisting of solely n-heptane and iso-octane).
According to Wikipedia

 

15.1 would melt the engine. I tried a 110 map for testing and it starts off at 14.7, literally get lean engine pops when you twist the throttle.

Couldn't imagine 15.1

 

Been running 13.8 to 1 xied's on my Softtail for 4 years now and I'm very pleased with the performance - plus a big oil cooler.

 

Couch I modified and loaded another map with 13.8 - I'll test it out. Did you by chance reduce your idle or leave it stock? I'm assuming you are using a PV1 which you can change your idle on the fly.

 

Folks stoichiometric for emissions is 14.6 to 12. Stoichiometric for power is 12.5 to 1.

The science of afr's for internal combustion engines has only been around for a about a hundred years or more.

The easiest afr to ignite, makes the most power,coolest charge and fastest burn is 12.5/1. The hardest to ignite and slowest burn with the most heat is 14.6/1 but it yields the lowest emissions of the three gasses that EPA is concerned about. It was not ever used until the mid 70's when EPA began regulating emissions.

Engines that use 14.7/1 are called "lean burn" engines.

Rich is lower than 12.5 and lean is more than that value. A gasoline engine can run okay down to 10.0/1.