sounds like either the gap was too wide on the supers or the base co is way off and the +4's are masking it. posibly the oil fouling issue steve mentioned as well. these engines will run on about anything you skrew in there but, seem to run best on the supers when properly tuned and with all fuel components working as designed. these are the last of the "tuneable" engines from benz and require a certian amount of knowledge to get right, when they are right they are wonderful mills.
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
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