Author Topic: Jetting changes for increase in elevation?  (Read 1604 times)

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Joe66GT

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Jetting changes for increase in elevation?
« on: March 20, 2025, 06:17:23 PM »
  My wife and I are hopefully moving to the Boise Idaho area after I retire later this year. The plan is to ship my Fairlane but am wondering if I should make any carburetor changes before it gets out there. Looks like a 2400' increase in elevation.

  On a similar note, has anyone used or can recommend a transporter (preferably enclosed)? We had used Intercity when shipping my daughter's Mustang out to California in 2023 but now apparently they don't pick up inside of NY city limits (can't really blame them). Thanks, Joe S.

Chrisss31

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Re: Jetting changes for increase in elevation?
« Reply #1 on: March 20, 2025, 09:34:01 PM »
There is a guy here in CT with a single car enclosed trailer.  The company is Mad Hen Trucking, I can send you his info if you're interested.

jayb

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Re: Jetting changes for increase in elevation?
« Reply #2 on: March 21, 2025, 08:26:33 AM »
  My wife and I are hopefully moving to the Boise Idaho area after I retire later this year. The plan is to ship my Fairlane but am wondering if I should make any carburetor changes before it gets out there. Looks like a 2400' increase in elevation.


I'd suggest you get a good wideband air/fuel monitor and see what the A/F numbers look like where you are now.  Then, when you get to the new location, you can check there and get a good comparison of what has changed, and then tune from there.  Generally speaking, as you go higher in altitude, you will need to lean out the carb, but if you happen to be running rich now, it might get the carb in a better spot at higher altitude.  No way to know for sure unless you can monitor your A/F numbers.
Jay Brown
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MrRupp

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Re: Jetting changes for increase in elevation?
« Reply #3 on: March 21, 2025, 12:56:35 PM »
Here in Colorado, were right at 5000 feet above sea level. We always advance the timing 4 to 6 degrees from what the factory recommends to give the fuel time to burn. As far as the jetting goes is I'm old school so we just read the plugs and go from there. Like Jay said an A/F sensor would be the most accurate.
Clint

Joe66GT

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Re: Jetting changes for increase in elevation?
« Reply #4 on: March 23, 2025, 11:57:27 AM »
Thank you for the replies. I had an Innovate MTX-L gauge on the car that helped dial in my current combination but after another O2 sensor failed I removed it. I'll have to look into getting another one when we get out there.

Chrisss31 - thanks for the heads up on Mad Hen trucking. I found his info online and reached out to him.

cjshaker

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Re: Jetting changes for increase in elevation?
« Reply #5 on: March 23, 2025, 08:20:46 PM »
On a carbureted engine, once you get the jetting correct with an A/F gauge, you don't need to leave the O2 sensor in, like you would with fuel injection. Just tune it, remove it and plug it.
Doug Smith


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