What´s wrong here? Been driving this car for a few days not being satisfied how it runs and decided to do something about it. It´s a -54 235 with newer head (3836848) and Isky Racing Cam, orig. carb and intake. Also original header. I bought and installed new plugs, condenser, points and coil and it runs better, not yet good enough. Idle is pretty nice, cam makes a little vibration but not much. Vacuum gauge shows around 17-18 on idle. Here is the mystery part. I can´t seem to make the dizzy vacuum work right. When revving the engine, dizzy moves CLOCKWISE!! WHAT THE ****? Vacuum line is properly attached to dizzy and carb, no noticeable leaks but dizzy moves like it´s pushed not pulled by the vacuum.
Vacuum is high when the throttle is closed, like when idling or highway cruising. Open the throttle, vacuum drops, so dizzy will move clockwise.
Yes, what ^^^ said. Your vacuum advance is working like it should. Check your timing though - these motors on today's gas like a lot more initial advance than the book says. A good rule of thumb is to keep advancing the timing little by little until you notice a slight pinging under acceleration, then back the timing back until the pinging just disappears. On my '54 engine, when I use my timing light the timing mark is barely visible in the little window but the motor runs strong!
Not all vacuum advances are the same. They match the engine years which had different cams, carbs and distributors (weights and springs) over the years. Get the later 58-62 truck advance (not car). And the same year distributor. They match the 261 cam grind and give the best advance curve when upgrading your cam for the street. I use these in both of my rides and get 20 mpg and as much power as possible with stock diz and advance. A racing cam may not even need a vacuum advance, but may be better with a modded optimized distributor and matching advance curve.
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