Do I need to adjust carb for altitude?

[mjeansonne]

Here in the Bayou State (Louisiana) we are 77 feet above sea level. We are planning on heading "way up Nort to dem Colorado Spring) this summer. Do I need to be concerned about carburetor adjustment when I reach the altitude of Colorado Springs?

[Pat Dilling]

You should probably at least adjust your idle speed upwards. It would not be a bad idea to adjust your mixture screws as well for smooth running. Maybe some of the local folks CO can chime in.

[blackhawk61]

Spent 8 years in Colorado........Smaller jets are required if You live there.

[mjeansonne]

Not going to live there. Just going to the International Meet and visit some family members who live there. So this questions deals more along the lines of any temporary fixes I may need to accomplish when I start going up in altitude.

[Carl Purdy]

When we were in Colorado with the 51 we were up looking at Buffalo Bills burial spot I opened the air screws and retarded the timing a little bit and seems to run OK. DON'T use 85 octane in your Stude it don't like it.

[WCP]

Do a search for the post entitled "R2 Carburetor altitude Adjustments". Lot's of comments and opinions. I'll repeat here Carter's rule of thumb for AFB's - Above an altitude of 4000 feet, reduce primary jet size by .001" for each additional 1000 feet. Therefore, for an altitude of 7000 feet, the primary jets would be reduced .003". This would be more easily accomplished with a step-up rod increase, if you can find one the yields a comparable reduction in mixture.

[Carl Purdy]

[Welcome]

Here in the Bayou State (Louisiana) we are 77 feet above sea level. We are planning on heading "way up Nort to dem Colorado Spring) this summer. Do I need to be concerned about carburetor adjustment when I reach the altitude of Colorado Springs?

Hey, maybe there will be a crew there to reset your timing and air/fuel mixture when you pick-up your registration package!?!? That certainly could explain why the registration fee being charged for the SDC 2013 Colorado Springs IM is the "highest" ever!!! see here: http://www.studebakerdriversclub.com/bod_20120228.asp and here: http://www.studebakerdriversclub.com/bod_20120514.asp

[bezhawk]

Yes, you can put in "fatter" metering rods. It takes about 30 seconds per side for an AFB. WCFB's are just about as easy. Strombergs......not so much.
They can tolerate a bit more timing at altitude.
You may need to turn in the idle adjustment screws a little. (there are no "air adjustment" screws as mentioned earlier)
You'll lose a bit of power at altitude, but on the bright side, octane requirements are lowered.

[BeeJay]

Went from Mich to Wyoming with my street rod.Adjusted idle stop. No problems. Ran a little rich, but we wern't there long enough to bother with.
B0b

[52-fan]

When I took my 52 to Estes Park back in the 80s all I had to do was open up the choke. It would barely run when cold in the morning with the choke closed.