This is from an older thread that disappeared when forum 1.0 crashed, thought I'd repost for those who haven't seen it. Also still posted on the Concours Mustang forum.
Other than service parts, we all know there was no HiPo 289 engine for 1968. But based on this fuel pump (and a few other parts), it appears Ford initially had plans to produce it for the Mustang.
Ford part number C8ZZ-9350-A, Carter number 4543S. It has dual springs and appears to be exactly like the 66-67 HiPo C6ZZ-9350-A, Carter 4201S unit, with one exception...it has the larger 3/8" inlet. Tim Lea, Bob Mannel, and Fred Ballard were instrumental in helping identify this. Below is a copy of the listing from Tim's 68 specific MPC, as you can see it shows the application as "
F Special (with 4/B carb.)...8...289", a car that was never built. The assumption is with the car on the drawing board Ford had to develop this pump to accommodate the larger 3/8" fuel line for 1968 since the 4201S had a smaller 5/16" inlet.
Dave






