64 Monza low on power

[Ron64Convertible]

Does this need to be done prior to balancing the carbs? It has it listed in the manual before the balancing section.

[terribleted]

You will get a better balance on the carbs if the idle speed screws are set and evenly adjusted. Carb balance has to be WAY WAY out to cause a big lack of power by the way. Like one carb opening and the other essentially not opening.

[Ron64Convertible]

I don't think the carbs are that far out and they both appear to be functioning although they probably are not synchronized properly. I just need to eliminate one thing at a time. This shouldn't be such a hard problem to solve, but I am missing something.

[terribleted]

drivability issues can be a pain sometimes. I always start with the basics and easier things to try (like swapping in different condenser, coil, points, putting points back if electronic unit in use, etc.) and working toward wore involved things. Verify everything. Getting full throttle? How is fuel flow volume (not pressure but volume)? Re-check thing you know are good cause you checked them last week. Eventually you will likely find the answer. Do you have another set of carbs to try?

[bbodie52]

Did you ever get a chance to compare the appearance of the spark plugs — looking at the appearance of the electrode and insulator on each spark plug and specifically comparing the appearance of the spark plugs from the left bank versus the right bank? If a carburetor fuel passageway is plugged or partially blocked on one side, the result would be a very lean fuel/air mixture on the side that is supported by a faulty carburetor. You would in effect be driving on engine that was running on three cylinders, with the other three cylinders being nothing more than an air pump (if the fuel component is missing). Such a difference, if it exists, should be readily apparent in a significant difference in the appearance of the spark plugs when comparing one side with the other.

The problem you describe with the general absence of power at speed would most likely be caused by a faulty carburetor on one side or the other, or by a distributor centrifugal advance problem with the timing is not advancing at higher rpm. If you do note a difference in the spark plug readings on one side of the engine as opposed to the other side, you should look at substituting the carburetor on the questionable side, or at rebuilding the carburetor on that side. You could try disconnecting the throttle linkage on one carburetor temporarily and driving the car to see if there is any change in performance. If one carburetor is "dead" and you disconnect it, driving the car with a disconnected carburetor would not reveal a significant performance change. If you disconnect the "good" carburetor that was doing all the work the engine was essentially not accelerate at all.

This method of component substitution or isolation often helps to identify a faulty component. If a faulty carburetor is revealed you can aggressively deal with that problem by replacing or rebuilding the faulty carburetor.

[Ron64Convertible]

No carbs that are any good that I can swap. I still have a few items that were suggested that I haven't tried yet. I'll keep posting if anything comes up.