elevation and carb adjustment


4 replies to this topic
  • pbusanga

Posted August 18, 2005 - 04:17 AM

#1

hi please correct me if i am wrong but i thought that at sea level you had to lean out the mixture and as you gained altitude you had to richen the mixture adjustment, or do i have this the wrong way round.
the reason i ask is because i was told to richen the mixture on my Edelbrock carb as i was at sea level
thanks

  • AzMtnThumper

Posted August 18, 2005 - 05:38 AM

#2

You need to lean out your mixture at higher elevations since there is less atmoshperic pressure (less air) at higher elevations. At lower temperatures you need to richen your mixture to take advantage of the increased air density.

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  • blueridge

Posted August 18, 2005 - 07:24 PM

#3

Is it true that the Edelbrock carb, with its externally adjustable needle position, is a better carb for major elevation changes than the FCR?

Assuming you don't need to run WFO (and therefore depend only on the main jet aperture), it seems the needle position adjustment would be enough.

  • AzMtnThumper

Posted August 18, 2005 - 09:05 PM

#4

Is it true that the Edelbrock carb, with its externally adjustable needle position, is a better carb for major elevation changes than the FCR?

Assuming you don't need to run WFO (and therefore depend only on the main jet aperture), it seems the needle position adjustment would be enough.



That's what I've heard about the Edelbrock. I want one.

  • Cedarwilly

Posted October 16, 2005 - 11:49 AM

#5

I noted on the Edelbrock sight that the carb is factory set for 1500 feet. So at sea level, one would richen the carb from the stock, as delivered setting. More air at lower elevations requires more fuel.

Then, as you ride higher, or the tempature shoots up to 100's, there is less air, so one leans out the carb to keep the proper fuel air ratio.

Temp and elevation are the two big variables. Barometric pressure also affects jectting, but it is a quite minor influence on jetting and usually is disregarded.

So yes, you do make your E carb richer when at sea level.





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