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> Eleveation change
pacman
post Aug 2 2016, 12:20 AM
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Alright guys im a newbie 19 year old that doesnt know much termanology but figured I can maybe ask the pros. I want my 73 1.7 litre (switched to carbs) and drove it from Portland elevation 50' to Bend which is 3,600'. Many people say many things but the most common one is to rejet the carburetors with bigger jets. Is this something a novice kid can do on his own? The car does seem to be running a little lean. Any insights and advice are appreciated!
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sixnotfour
post Aug 2 2016, 12:53 AM
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Yamaha blaster forum ,,but lotsa of info..should really confuse you or not,,
http://www.blasterforum.com/threads/effect...ordingly.39872/
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sixnotfour
post Aug 2 2016, 12:59 AM
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simplified;
http://www.lcengineering.com/LCTechPages/p...%20Altitude.pdf
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r_towle
post Aug 2 2016, 05:32 AM
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The beauty of Weber carbs or Dells is that they are easy to tune and quick to change jets. Learn this art form and be the carb guru for the next generation....there are several good books and tons of online tutorials.

First off, take a pic of your carbs and post it here so you learn what you have and then know where to start.

Rich
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zambezi
post Aug 2 2016, 07:16 PM
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In theory it should be acting just the opposite. At higher elevation there is less oxygen available to the given supply of fuel, hence will run richer. At sea level there would be more oxygen allowing a leaner mixture.
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pacman
post Aug 3 2016, 12:00 AM
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Thanks, will post pics and get back to you guys!
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anderssj
post Aug 3 2016, 07:15 AM
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Some additional tuning basics from aircooled.net:

http://www.aircooled.net/vw-carburetors-jetting-102/

This will help you get a good solid baseline to work from . . . .
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pacman
post Aug 3 2016, 11:52 AM
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So they are Webee 34's. I would be curious if this leads to any other information thanks!


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Mark Henry
post Aug 4 2016, 06:20 AM
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I'm personally not a fan of the ICT baby webers, I'd save some dough and get a set of IDF's.

The best tool is a wideband O2 meter, even a rookie can get near perfect AFR when jetting with a wideband. They are now fairly cheap at around $200, sometimes you see them on sale for even less coin.
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Mike Bellis
post Aug 4 2016, 07:06 PM
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QUOTE(zambezi @ Aug 2 2016, 06:16 PM) *

In theory it should be acting just the opposite. At higher elevation there is less oxygen available to the given supply of fuel, hence will run richer. At sea level there would be more oxygen allowing a leaner mixture.

(IMG:style_emoticons/default/agree.gif)

It should be running richer and require smaller jets at altitude. Once you tune to elevation, do not drive back to sea level or you will be dangerously lean.
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