Why Your 3614S Measures 3/4" (Instead of 11/16")
Carter's official technical charts for the 3614S blueprints list an 11/16" pump cup, but you are holding a 3/4" bore in your hands for one of two highly common reasons: [
1,
2]
- Mid-Year Production or Heavy-Duty Casting Changes: Carter frequently updated castings mid-run or shared cast bodies across different assembly lines. Heavy-duty applications (like the high-performance Chrysler 383/413/426 Wedge big blocks that the 3614S belonged to) were routinely upgraded to the larger 3/4" accelerator well to dump more fuel and eliminate the off-the-line flat spot inherent to moving massive Mopar B/RB-body cars.
- A Past Machining Rebuild (Sleeving/Boring): It was incredibly common for commercial rebuilders in the 1970s and 1980s to clean up pitted, corroded aluminum Carter wells by boring them out exactly 1/16" oversized to accept the larger 3/4" plunger cup.
Has anyone else run into this issue? Both bores and scored up a bit, so I don't think they were machined any larger in the past.
Allan