high altitude problems, need advice please!

[jrm27]

Hey everyone-

I just moved from portland, or to Vail, CO. and I am having some issues with my 67! I burned out my transmission in Utah and had that rebuilt. When I started the car in Ogden, it ran like crap (I think because of the drastic altitude change between Ogden, UT and Portland ~5,000 ft, I think), so I adjusted the carb a little bit and it ran pretty good until I started climbing higher into Colorado. Once I got to Avon, CO (~7500 ft) the car was basically just crawling along even though I was flooring it all the way. No power, but I was still getting normal gas mileage. I am so confused at what I should be doing now to remedy that problem.

The car is a straight six 200ci, with a single barrel carb and a newly rebuilt c-4 transmission. I'm wondering if the carb just isn't getting enough air into the engine since it's such a high altitude. Any ideas? Any help would be immensely appreciated. I'm seriously at a loss. Thanks!

-jrm

 

[Ronstang]

You are right that the engine is not getting enough oxygen compared to what is it used to and "set for" so you will have to adjust the carb. You will need to contact Pony Carburetors and find out the appropriate jet to run and you will have to readjust the idle mixture to lean it out a bit because this circuit has an affect on how the car runs all the way up to about 2000 rpm or more. You simply have too much gasoline available for combustion with the limited amount of oxygen at high altitude. You can get the car to run good again but it will never make the power it would at sea level even when properly tuned. Good luck.

 

[jrm27]

thanks for the quick response! That makes sense. So if I adjsut it correctly, I should be able to drive rather normally shouldn't I? I mean, I can barely get up a very small hill right now. I jsut have to throw it in 1st and hope no one is coming up behind me too fast!

Is there anything else I can do to increase the performance... upgrade to a 2 barrel carb, soem kind of air intake system, any ideas? I honestly don't know that much about working under the hood, I'm still learning something new everyday, so excuse me if my assumptions are basic, elementary, and/or way off course!

Also, I can't find any accesible information for Pony Carb. I find a website, but it comes up "page not found"... any ideas how to get in touch with them?

 

[brianj5600]

Might need more advance in the timing too.