I knew even before I'd started this project that the stock Chrysler EFI system from the 4.0L HO Jeep six-cylinder would need some tweaking to work with my 4.6L stroked six. Increasing displacement meant I'd need more fuel. More fuel meant I'd need more air, and more of both meant I'd need a way to convince the stock computer to play along, or else driveability, economy and power would all three suffer.

First, I started with 24 lb/hr blue-top Ford 5.0L V-8 fuel injectors from FiveOMotorsport. Some stroker builders have reported that they've been able to get their stock 19 lb/hr injectors to work, but the math shows that the stock injectors would be at their maximum duty cycle supplying a stroker, so I went with the Ford injectors to be on the safe side. While the injectors worked with the stock Jeep fuel pressure regulator (fixed at about 37 PSI), I still encountered lean-outs with that setup, so I decided it was time to step up the pressure to the 49 PSI the Ford injectors were meant to run at.

Read the Whole Article