vaccum advance

[Nightengale]

Hi Nightengale,
all this because you are missing the vacuum tap on the #2 carb?
I have a 78/79 XS11 carb rack if you want it.
Butterflys work, all 4 needle jets missing & possibly 1 or 2 needle tips bust off in the carb bodies,
all the slides are stuck full up, dunno if the diaphragms & springs are even there, ditto float bowl internals.
With all that, the body castings look OK and yes! the #2 carb has the vacuum connection.
I paid $30 for them, yours for that + postage.

thanks for the offer, but i think i am gonna keep the carbs, because my buddy that sold them to me said that he would be able to make the carbs work with the vaccum advance like this
http://www.xs11.com/forum/showthread.php?t=36055

[motoman]

The first half of that statement is true, the second half isn't. Vacuum advance is wholly dependent on engine load, i.e. throttle opening or manifold vacuum. The bigger the throttle opening, the less manifold vacuum you have. Now, there's different ways of hooking it up that gives different results, but the most common method (and the one used on the XS) is to connect to 'manifold' vacuum to give more advance the smaller the throttle opening.

Actually Steve, the "most common" vacuum advance AND the XS's IS ported vacuum, not manifold vacuum.

[DGXSER]

Steve,

Just to finish the thread jack....Yes, it is a TH400 with manual shift kit 2500 stall speed converter. Rear is a Currie version of the ford 9" with 3:73 gears, detroit locker. It also has a little bottle in the trunk. That will shave a full second off the 1/4.

One time, only once, I tried running that car with the exhaust opened up downt he strip on the street Eagle Gts. Never again!! took off the line, broke the tires loose, shifted up through second to third still just sliding around. After I stopped 1/3 of the way down the track to finally get the rear end planted, I took off in third. Still ran a 14 second. Then I stopped to change my under-roos.