I have overhauled my q-jet and it is ready for installation on the weekend. I did some e-research (including pirate search) and found a really neat blurb on tuning a q-jet, but now I cant find the URL.:mad:

Please help. I have a vacuum guage for measurin' the sucka. Its a 170XXXXX.

Thanks

Ben

This is what I was looking for. Everyone can stop worrying now!:flipoff2:

http://www.pirate4x4.com/forum/showthread.php?s=&threadid=48551

You can really only adjust the idle mixture on the q-jet.. everything else is done by changing metering rods.. The l;ocal auto parts place should have a book all about q-jets if you're into that.. Mine runs fine with a good cleaning and setting the idle.. Just has a little stumble when the secondaries open.

Just has a little stumble when the secondaries open.

There is an adjustment for that...if it bugs you enough to bother messing with a fine running carb:p

Thanks Guys :)

There is an adjustable thing that has some sort of control over the mid range rods. It limits the flow of gas from under that little piston that pulls the mid range rods down. Is that what you are talking about Tankota, when you say there is an adjustment?

The vertical cylinder that the piston sits in looks like it is connected to manifold pressure at the bottom, and float bowl pressure at the top. There is a screw adjustment that chokes off the flow from under the piston. As far as I can can tell, the rods will move downwards as the manifold vacuum increases, and the rate at which they move down is controlled by the adjustable thingy. I can guess that much, but as far as the effect it has on tuning, I have no idea.

Cheers

Ben

Kinda figured I could bend the hangar for those 2 rods and get it to meter right... But I've screwed with this carb so much (it's backwards-mounted, too), that I'm happy that it runs very well with no choke, and works at nearly all angles.

There is a screw adjustment on the spring for the secondary butterflys. This screw can increase or decrease the spring tension to make the secondary butterflys open quicker or slower.
Mine worked good enough to not have to mess with.