Motorcraft 2150 ported vacuum
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- 488
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- Location
- Atlanta, GA
- Vehicle(s)
- 1979 CJ5 Renegade 258, t-18 pretty much stock except for a later model aluminum intake manifold and Gronk 2150.
Just an update.
We pulled the carb to seal the spacer and eliminate any possible vacuum leaks. It was still running poorly and the plugs were bone white indicating a lean condition. As for the ported vacuum showing too much vacuum at idle I surmised the idle screw was too far in and uncovering the transfer port. Even though the idle speed was not that high due to the timing being off. My suspicions were confirmed when I pulled the carb.
As for the timing we disregarded the timing marks and set the timing for the highest vacuum which put the timing mark off the scale. Odd but it seems to run OK (not great though) and the plugs are nice chocolate tan color. The fuel screws are out 2 1/2 turns so we may have to go up a size on the jets from the #48 we have now.
We pulled the carb to seal the spacer and eliminate any possible vacuum leaks. It was still running poorly and the plugs were bone white indicating a lean condition. As for the ported vacuum showing too much vacuum at idle I surmised the idle screw was too far in and uncovering the transfer port. Even though the idle speed was not that high due to the timing being off. My suspicions were confirmed when I pulled the carb.
As for the timing we disregarded the timing marks and set the timing for the highest vacuum which put the timing mark off the scale. Odd but it seems to run OK (not great though) and the plugs are nice chocolate tan color. The fuel screws are out 2 1/2 turns so we may have to go up a size on the jets from the #48 we have now.
