I have an 87 B2200. It has a carburetor with a whopping 85 H.P. at sea level. I live in Parker, CO with elev. at 5500 - 6000 ft. I advanced the ignition timing from 6 deg. BTDC to 9 BTDC. There is no Air Mass flow sensor (that I know of) on this engine so I'm trying to compensate for the thinner air. It seems to have a little more power and I don't hear any pinging or knocking. Does that make sense to do on this vehicle at this altitude?

Thanks for any opinions,

Phil

 

As long as you do not get any pinging or pre-ignition then advancing the timing a few degrees will not hurt anything. The truck actually does have a high altitude compensator for this already however. Do not have a pic but it is mounted on the right fender area to the rear of the charcoal canister. It is either silver or gold in color with I belive a black top (not sure on thatf), shaped like a small cylilnder with top cap being larger. Should have three vacuum lines attached to it that all go to the carburetor. If it is functioning correctly then you should be able to remove each of the three lines at the carb and blow into them without restriction at altitudes above 1640 feet. Below that elevation the lines should be blocked off at the compensator and you would not be able to blow thru them.

 

Babyhuey comes thru with the answer once again!

Thanks for the info on the altitude compensator. I'll check the vac lines as you described.


Muchas Gracias,

Phil