When you are asking the size, do you mean the physical size?, or the amount of fuel they flow? If you are asking the physical size, 92 would have the 7mm injector bodies. I don't have the answer to how much they flow. They stock injectors are made by bosch. You can get a noticeable power increase buy adjusting the full power screw on your injection pump, and that's free. I believe there are instructions in the tech articles on hear.
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04.0 HO QC 4x4 LB auto transgo VB, stock, for now
Sold 91 now intercooled W250, 388HP 923TQ on #2 only 436HP 968TQ on meth
Work Truck, 93 W350 LE Dually 5Spd almost stock