by John Grady and Allan & Gloria Moon
Over the years, various people have collected information on the fuel injected 300D. Recently John Grady
collected and digested this material. He writes:
A sincere thanks to Gloria Moon and Jim Bartuska for entrusting me with this data. There is quite a story here.
As it turns out, a lot of the material is internal engineering documentation of the efforts to get the first 12
cars to run right for a press release showing of the 300D FI in Miami. Chrysler had one hell of a time even with their engineers there to support the effort. The cars were barely drivable, but managed to get through the show.
The result of the Miami show was a list from the engineers of things that required immediate correction to the FI system. Some of the problems were inherent in the design and some were troublesome FI parts. After the Miami effort, they fixed only what they could fix. The engineers concluded FI was not ready for production but management liked the idea of it and production continued.
I moved on to the 3 best test reports, called "Technical Reports" , especially #4511-33 , "A676 Bendix Fuel Injection System Evaluation", dated 6-1-60. A significant takeaway in 1960 was that there was no net gain in output, despite some wild claims and published graphs early on, and that fuel economy suffered, even with highly tuned systems of closely matched parts.
Chrysler had an initial order for 85 FI units with Bendix and a planned program for a second generation of it starting with #86. I do not think 85 were made.
The Bendix system came from outside Chrysler and was aviation based. It had overrun an older internal program for a continuous flow FI that had been ongoing at Chrysler since 1955. The idea of FI was, surprisingly to reduce cost; apparently Carter carbs cost a lot even then.
This older Chrysler FI project was probably like the GM TBI. As the problems with the Bendix unit became apparent, this project was briefly resurrected in combination with new "Ram Manifolds" (late 1958) but it too, had too many problems "that had not been resolved". All the #86 Bendix and later FI efforts and engineering projects were subsequently cancelled. "Lack of durability" was the main issue but there were also a few quite alarming specifics too (fire for one, on one Electrojector in Miami).
One report is a single page from "Service Division". It outlines the main issues for them but ends with "complete replacement of the system , with dual 4 bbl carburetors is the only solution" for repeated complaints.
The replacement was, in retrospect, wise. This was not a good thing to have on your car in 1958, despite the aura that has grown around it since then.
Some of the major inherent design problems were the injectors themselves were too slow to close, initially taking 4 msec to shut. Later, after much truly heroic effort, they got it down to 1.5 msec. The injectors were also very inconsistent, bringing on cylinder A/F matching issues.