I have the 3.4 crate engine (not sure if it's the HT though) and I am using the 4.3 with the 4.3 injectors. Even though the injectors are bigger the computer still uses the 02 sensor data to put more or less fuel in. just the 4.3L injectors will never be the weakest part of the chain anymore. I also have the 2.5" exhaust now from the y pipe. Sounds a lot better!

91 Trooper LS, 5 Speed Manual
3.4L Engine w/4.3L Throttle Body
Snorkel, 31" Pro Comp MT Tires, 2"lift,
ProComp ES9000 shocks and steering stabilizer

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