914-6 Weber 40IDA adjustment problems Options

[hars914]

I just rebuilt my carbs for my six. I got the car warmed up and started tuning them.
First when I turned the mixture screws on one of the carbs the idle did not change unless I just about turned them all the way in. The other carb did not change much
at all when I turned the in or out. When I tried to adjust the air correction screws on both carbs I could not get them to all read the same on the sync tool. I was geeting a lot of backfiring thru thru the carbs. What is my problem here???????

[john rogers]

You need to make sure the fuel pressure is about 3.5#, if much higher it'll flood. How is the float level? If you do not have a PMO gauge you'll need to buy one (I bought two so I can do one side at a time) so the floats are not to high or too low. If too low the engine will run too lean, too high and it will get too rich. Since I imagine you preset the mixture screws correctly that you had to turn them all the way in makes me think that side is flooding. Did you unhook the crossbar linkage and do the carbs seperate? If connected it will be hard to get them to match up. The spitting through the car can be from a lean cylinder unless you have 906 cams which have a lot of overlap and they spit no matter what usually. You can have one cylinder on a side be rich, one lean and one right on and never know which is which. I use my pyrometer to measure the exhaust from the cylinders to see if their temp is close, if one is low, it is too rich, etc. Good luck.