Fat / Lean Question

[vdrivenman]

a question for you motorheads!
if an aspirated carbed engine is set up to run fat in sacremento cali, what will that set up be like in southeast Texas?
will it remain the same ,get fatter, or lean out ??
i have NO idea and would not want to take a chance on ruining any parts by cranking or running a motor.
thanks for the responses !

[Towndrunk]

a question for you motorheads!
if an aspirated carbed engine is set up to run fat in sacremento cali, what will that set up be like in southeast Texas?
will it remain the same ,get fatter, or lean out ??
i have NO idea and would not want to take a chance on ruining any parts by cranking or running a motor.
thanks for the responses !
Are you talking about that outboard you bought?? Anyway, if it's fat up high(thin air) it'll be fatter down lower.

[502 JET]

At a higher elevation there is less air there for the engine would run fatter with increased altitude.Go down in elevation and there is more air the engine will run leaner.How much this will change I dont know.The east coast is flat and we dont have to worry about elevation changes.

[GofastRacer]

a question for you motorheads!
if an aspirated carbed engine is set up to run fat in sacremento cali, what will that set up be like in southeast Texas?
will it remain the same ,get fatter, or lean out ??
i have NO idea and would not want to take a chance on ruining any parts by cranking or running a motor.
thanks for the responses !
Depends on the elevation between the two places, high elevation=leaner, low elevation=richer!..

[502 JET]

Depends on the elevation between the two places, high elevation=leaner, low elevation=richer!..
I must be confused?
Higher elevation less air it seems to me that you would run richer.

[WannabeRacing]

You are not confused, Art just spoke so quickly, that he got it mixed up. You will get fatter at higher altitude, and leaner at lower adjusted altitude.

[Towndrunk]

Lets try this again. When you go high you run leaner jets. Right? Hell I dont know I run fuel injection and the dam ecu does it for me. :cry:
When you are under a truck and tightening header bolts do you turn the wrench the same way you do when you are leaning over the fender doing it? :220v:

[GofastRacer]

You guys smokin bad panty hose or what????.. Reread the post, high elevation=you need to lean out, low elevation you=need to fatten up!.. :rolleyes:

[Moneypitt]

You guys smokin bad panty hose or what????.. Reread the post, high elevation=you need to lean out, low elevation you=need to fatten up!.. :rolleyes:
As always Art says it plain and simple, however, you also have to consider the "corrected" altitude. Elevation is only a minor factor when figuring jets, be it injected or carbed. The volumetric air pressure is what changes in elevation differences, but, high/low pressure fronts moving through an area can have tremendous effects on that pressure, hense the term "corrected' altitude. You also have to factor in temperature and humidity. In order to accurately calculate your mixture you must have a baseline to work from. Without this data, it's a crap shoot until you "try" it. If you establish a base line at a given air density, then you can tune to the next air density you travel to, or the changes in density that occur in the same place as highs/lows move through. This applies in your own backyard, as well as where you may travel to........MP

[vdrivenman]

the motor is a 468bbc,14 /1 motor, tr w dominators.
motor is currently set up rich,fat in sac,cali. this motor has a soft tune on it,timing slightly down,as is valve lash. i just do not want to HURT this motor.it will be for lake play not racing.
it is probably coming to the gulf coast of east Texas at 7 ft above sea level,hot 80-90degrees,% humidity usually about same as temp.
so i guess i'd better by a pyrometer(spelling)& install it to give ma an idea.
cause i'm confused!

[GofastRacer]

As always Art says it plain and simple, however, you also have to consider the "corrected" altitude. Elevation is only a minor factor when figuring jets, be it injected or carbed. The volumetric air pressure is what changes in elevation differences, but, high/low pressure fronts moving through an area can have tremendous effects on that pressure, hense the term "corrected' altitude. You also have to factor in temperature and humidity. In order to accurately calculate your mixture you must have a baseline to work from. Without this data, it's a crap shoot until you "try" it. If you establish a base line at a given air density, then you can tune to the next air density you travel to, or the changes in density that occur in the same place as highs/lows move through. This applies in your own backyard, as well as where you may travel to........MP
Still amounts to same shit though don't it!, LOL...

[Sleek-Jet]

Leaving everything alone, the engine will run leaner the lower you go (more oxygen to fuel)... so, you might need to fatten it up a little as you go down hill. How much depends on the conditions, like Moneypitt said.

[AzMandella]

According to my Web Search Sacramento is only 25 ft above sea level.So the only difference you need to worry about is Temp and humidity which correlates to air density.My suggestion would be to put some new plugs in gapped properly and go out and make a pass and shut it down immediatly and while your floating pull a plug.Look for the burn mark not just the color.The closer to the bend in the electrode(lean) the closer to the first thread(rich).If you really want to be fat get the burn mark to be just above the first thread.

[AzMandella]

Depends on the elevation between the two places, high elevation=leaner, low elevation=richer!..
Actually Art to the average person it does look like you have it backwards depending on how you read it.What I'm saying is you could read into it two ways :argue: .Besides smoking pantyhose tastes like shit from what I've heard. :rollside: