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Everyone has been super in giving answers to my questions, however I still have another. I have added 4in exhaust, ripped out the air snorkel, have a K&N filter. I have been reading a lot about bumping up the pump. With the added air coming in and going out will bumping up the inj pump help? If so how much should the pump be bumped up safely? I need all I can get in HP with the least ammount of cash outlay at the present time. Thanks gordon.
 

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'93 is mech inj - simple adjustment to turn up the fuel on your pump.

QM posted that about three weeks ago.

Really shouldn't do that without gages and charge-air cooler, tho.
 

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Your working on your '93? Its fairly easy to adjust the Leaf spring inside the pump on the truck. You will need a 5/16" socket or Torx25 bit to remove the top cover screws, a ½" wrench to loosen the guide stud lock nut, and a 3/16" allen to remove the guide stud. Before you remove it, note the distance between the top of the lock nut and the head of the guide stud screw so you can get your governor hi idle back to where it's supposed to be. Then you will need to roll the engine over until the 5/32 allen screw is visible looking through the hole in the top of the cam ring inside the pump. 1/4 to a 1/2 turn depending on how much fuel you want. When you reassemble the min/max gov, be sure to put the spring back inside the guide stud bore, and make sure you get the shutoff solenoid in the top cover back on the pump properly.
 

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This is the easiest method and least prone to screwing up your pump by taking the top cover off. Don't take the top cover off.

Turn up the fuel by taking off the small cover on the drivers side of the injection pump. It is very small, and has 2 - ¼” head screws holding it on. You will need to remove the throttle cable and bracket to see the cover. Once this cover is off, a little bit of fuel will spill into the engine valley. What you are looking for is a small 5/16th allen screw under this cover that appears through a small access hole. The screw rotates as the engine rotates so you will need to have a large ratchet or breaker bar on the crank pulley nut to rotate the engine while you look for the screw to appear in the access hole. You will need a small flashlight and mirror to see this screw. It helps to have a buddy turn the crank while you watch for the screw. It does help to remove the throttle cable bracket and detach the throttle cable from the injection pump. You may also have to move the throttle linkage to get to the access cover and fuel screw.
Once the screw is in sight use a good quality 5/32th allen wrench to turn it. To increase fueling, turn the screw clockwise 1/4 of a turn clockwise. Once the screw has been turned put it all back together and go blow some smoke. Might be wise to make sure the breaker bar is off the crank to, otherwise it might give new meaning to hand cranked.
 

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Or you can do it that way, probably have to rock the pump on its side to get a good view, definitely need a mirror. He's right, if you can do it this way, lessens the chance of screwing up the governor/shutoff solenoid, better for novices.
 

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Professional trade secret

Actually, if your good enough, you can pull the cover off the front of the engine to gain access to the pump drive bolts. Turn the engine till the pump drive pin is at the ten O'clock position. The allen bolt should then be aligned in the window. Only a "Pro" would know that.
(Caution: . Professional trade secret. Should only be attempted by professional experienced technicians. All others do it the hard way)
 

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I still do it the hard way, one hand on a ratchet turning the alternator while looking through the cam ring from the top cover. That is a neat tip about the drive pin, I never even thought about doing that.
 

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I thought it spilled all the fuel, DP.:) It took a lot of cranking to see fuel at the injectors after

I pushed the pump over but it was a still a tight fit with the intake off just to turn those two 1/4" screws. Saw the allen screw first 5 degs of turning the crank. lucky me
 

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Next time you do it mark your harmonic balancer. Then you'll have a 50/50 chance of getting it right the first time without guessing.
 
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