DDEC Upgrades?

[Greg York]

On 6V92TA/8V92TA engines found in the late 1980s Newells, is it possible or desireable to upgrade from DDEC to DDEC III or DDEC IV?

[TechTalk]

It is our understanding that DDEC upgrades, for example from DDEC to DDEC II, III, or IV, are simply not practical to retrofit. The DDEC system is integrated into the engine and, to a lesser extent, the transmission. There is a wide variety of significant differences in a number of parts, as well as the wiring harness, between these differing versions of DDEC. You may wish to talk with your nearest Detroit Diesel distributor about your specific situation, as they have greater expertise on this issue than we. But we don't think you can get there from here. A final comment: modifications to DDEC though the years have for the most part been for the purpose of meeting increasingly stringent exhaust emisssion standards. We would not expect to see any performance enhancements as a result of incorporating a later version of DDEC.

[Greg York]

In what year did Newell start using 6V92TA and 8V92TA engines with DDEC? Were any or all 1987 coaches DDEC? What were the major advantages of
the DDEC computer controls?