Retuning a turbo spec IP to N/A?

DirtyWood

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I've almost got things where I want but was interested in how much adjustment is needed on the torque screw, or whatever the appropriate name is, to get close to N/A specs?
I turned down the internal fuel screw behind the access door but I still had way too much fuel and only about 3/4 inch of throttle travel from idle to WOT. Finally I realized this IP had the extra screw and turned it in 1.5 flats. On my IP the torque screw takes an Allen key and there is no lock nut to hold it in place.
Turning the screw in 1.5 flats made an enormous difference but it's all just trial an error guesswork on my part. Any tips are appreciated.
 

DirtyWood

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CCs? CCs?!?! We don't need no stinking CCs!! I have no idea how many CCs. Based on paperwork and the vehicle the pump came from my best guess is that it was factory spec for a turbo IP--this was not a high quality rebuild from a known vendor.
I haven't had a chance to go out and really put some strain on the new setup but just backing out the internal fuel screw about 2 flats and turning in the external fuel screw about 1.5 flats feels good so far. Engine starts right up without glow plugs, no smoke during normal driving, sounds pretty good if maybe a little quiet.
 

IDIBRONCO

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CDD lists the N/A pumps at 60cc and the Turbo pumps at 70cc. I'm running a Turbo spec IP i my Blue Truck at whatever setting they sent it as. With the headers and ported heads, it seems to be just barely enough fuel. If there isn't much wind, I can barely see black smoke when I floor it. It could be turned up slightly, but I'm happy with it for now.
 

Black dawg

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Since the torque screw just limits the max travel of the metering valve....just like if you limited throttle movement....I would back the torque screw out all the way and then adjust internal screw for smoke/egt. Can use the torque screw for fine adjustment
 

DirtyWood

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Well after a lot of minor adjustments it seems that turning IN the torque screw 2-2.5 flats made the most difference in terms of proper fueling over the full throttle range--before making any adjustments I only had about 5/8" travel between idle and WOT. The internal fuel adjustment seemed to be far less important than the torque screw as far as overall 'drivability'--backed out the internal screw about 1.5 flats. And again, the torque screw on my IP does not match up with anything I found online.
 
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