any tips for tuning weber 34ict? Options

[JOE M]

Curious about how to set the carbs up.The timing is close but may be out slightly.I started by turning the air mixture screws all the way in and than backing both off by 2 1/2 turns to start. I let the car idle and than I move 1 side until the car runs rough than back off the other way about 1/2 turn.I did the same for the other side. It runs ok but pops through the exhaust every now and than.It gets better when I take the throtle linkage off.I think my biggest problem is seting the idle speed screw. Is there something I should do prior to starting any other alignment?I read the procedure but I am stumped. What typically causes it to pop through the exhaust?I did check the vacum on both sides and they are real close ( within 1 of each other).

[hi4head]

Joe,
Rich is right on with his comments. If it helps to clarify any, I'm added some more pictures.

Here is a pic I took while doing the prep for my installation. Note the big barb fitting on the manifold. There should be one of these on each manifold. A hose simply runs between the two barb fittings. According to what I've read, this balances the carbs and helps in the lower rpm range.


Next is a pic that shows a couple of things. One thing that you'll need to do is to build a bracket for your throttle cable. (Or maybe there are some around for puchase now.) You can see the high-tech model that I created with some 1"x1/8" stock and some heavy duty washers. (It may not look like much, but it works.) Also in the photo is the line coming from vacuum port of the carb connecting to the front of the vacuum advance. My method is slightly different that what Rich described. I simply ran a line from one of the carbs to the vacuum advance. I have a T around so maybe I'll try Rich's recommendation. Finally, I have a short length of hose connected to the back nipple of the vacuum advance. I have plugged this off with a golf tee. I understand that not all dizzies have vacuum advance modules and that not all vacuum advance modules have the nipple on the back side. If yours doesn't have it, don't worry about this step. Also, if someone reads this section and really knows what should be done here, please advise.


Finally, here is a shot of how my linkage setup looks. My understanding is that there are a number of ways to accomplish the same thing.


I hope that this helps at least a little.

Chris