How do you adjust a carb for elevation? in california goin 600 miles to idaho

[440charger68]

so im goin on a road trip to meet some college friends in boise idaho and im driving my 68 charger. Im starting at 600 ft and ending up at 3000ft above sea level, so how do i adjust my carb for that elevation? i have driven to lake tahoe without adjusting my carb and my car pretty much lost all of its power  Its a 318 with a 600cfm 4 barrel if that helps me get a answer.

[ChgrSteve67]

No need to adjust the carb.
It might be a bit sluggish but nothing to worry about.

I did 6,000 miles in my Charger this summer reaching elevations over 7,000 feet (my Charger is tuned for sea level) pulling a trailer and only had issues when I tried to bury my foot in it.

If you racing then you would need to adjust your carb but if you just driving around don't worry about it.

Question:
What Octain fuel are you running?
If you running 87 then a 89 or 92 might help your detionation performance.
It definately helped my Charger in the higher elevations.

[A383Wing]

we drove the Daytona from Seattle to Talladega in 1999...never had an issue with any elevation and my engine is tuned for sea level

[RallyeMike]

Your car will run a little richer at high altitude, but that's not much to worry about unless it's already running rich. You have to change the jets to lean out the carb which is some work. Re-jetting is probably not worth the time unless you plan on staying there, and then it will just run lean leaving from home and coming back.

No matter what you do to the carb jets, your engine will make less power because the engine just can't suck in as much air at higher altitudes.

[HPP]

Question:
What Octain fuel are you running?
If you running 87 then a 89 or 92 might help your detionation performance.
It definately helped my Charger in the higher elevations.

Octane requirements actually drop with elevation increases. In Colorodo, all the pumps are 2 points lower than the equivilent sea level offerings.Now if the fuel is E10 or E15, than it is a whole nuther deal as 87 with 100% gas is a better fuel that 89 with E15.

Like others said, I wouldn't worry about a 3000' elevation change too much if your just driving around. However, you didn't say what carb you have. If it is a Carterbrock, you could easily and quickly change the rods in it to dial it in a bit better.

[heyoldguy]

[quote

Now if the fuel is E10 or E15, than it is a whole nuther deal as 87 with 100% gas is a better fuel that 89 with E15.

Really? Why is that?

[440charger68]

The carb is a holley 600 cfm double pumper, its a 318 and i think im running with jet size of #67. Thats good to know that i dont have to tune to elevation my car must have been running rich and as i climbed in elevation it must have gotten way too rich   and i always run premium gas. I heard gas back in the day was leaded 98 octane so premium is as close as i can get

[RECHRGD]

I had my car at Tahoe once and it ran so rich that it started fouling plugs.  I bumped the timing up a couple of points and it cleared right up.  I also doubt you'll have any issues at 3000'.   Bob

[HPP]

Really? Why is that?

The additive package that comes in blended fuels is not very stable. They have about a 90 day shelf life before the aromatic compounds start to evaporate. Additionally, they tend to absorb water much quicker, which leads to faster and further degradation and gives the impression that despite the higher octane, they are not as detonation reistant as straight gasline. The additional alcohol burns off much quicker giving poorer mileage and reduced power since most guys won't tune to an E10 level specifically over a gasoline tune

[heyoldguy]

So, once a gallon of gas leaves the refinery, how long before it is consumed? More than 90 days?

[Budnicks]

So, once a gallon of gas leaves the refinery, how long before it is consumed? More than 90 days?

That's a very good question... I would say it depends on supply & demand in what ever area it's going to.. I know It's piped all over in a gasoline pipeline distribution system, maybe they actualy add the additives when it reach's the distributors or in the fuel tanker trucks themselves or in the storage vessels at the gas stations maybe... It would be interesting to know, what, when & were

[mauve66]

here the additives are added as the truck is loaded from the local tank farm depending on the local customers recipe

[Budnicks]

here the additives are added as the truck is loaded from the local tank farm depending on the local customers recipe

That's what my Pops said also, didn't know whether to believe him or not he's kind of nutty some times, I know that he drove a fuel tanker for Shell Oil Co. in S.F. Bay area in the late 50's...

[Budnicks]

Most people don't know that gas is gas, the gas that goes in a Chevron station is the same as the gas that goes in the Shell station etc., it's the specific additives each company uses that make them unique, it's all the same stuff in the pipeline, it's all co-mingled together form all manufactures refineries, except for some small distribution Fuel companies & some large distribution & refinery hubbs...

[heyoldguy]

here the additives are added as the truck is loaded from the local tank farm depending on the local customers recipe

That being the case, it would seem unlikely the fuel would sour before it was consumed.

[ACUDANUT]

we drove the Daytona from Seattle to Talladega in 1999...never had an issue with any elevation and my engine is tuned for sea level

I have done that trip. Don't worry about it...You think they (factory) worried about it 40 years ago ?? NOPE.

[HPP]

No, the factory didn't worry about it much. Ass a kid,  I do recall being able to quickly idnetify out of state cars as they left large black clouds behind them as they accellerated.  High altitude tune ups where one of the top items on the list of "to do" things for transplants in to my area.