Unplugging the Map with a comp
#1
Unplugging the Map with a comp
I've read about a couple of people doing this and thought I'd give it a try. All you do is unplug the map sensor from the block but leave everything else alone. The comp feeds fuel in based on the boost reading from the MAP sensor. Well, if it doesn't have the reading coming from the map sensor, it throws in full fuel at 0 boost. Do not try this unless you have a comp. You'll throw codes and go into limp mode. I'm not sure about what happens with any other box. All of this was done with the comp on 5x5.
First notice is that I can floor it in park and a huge cloud of smoke comes out. Cool. So I put it in gear and proceed from a stop. First thing I notice is how responsive the truck is. Much more responsive than with the comp on 5x5 and the map plugged in. Smoke is also very easily produced. That's cool. I stomp on it from a stop light. BIG DIFFERENCE!! The defueling that I used to experience so badly from a stop on 5x5 is now gone. I would defuel so bad in first gear I could only see about 20 psi of boost. Now I'm seeing roughly 25-28psi. So first gear actually moves you now. Once you hit second it's an animal. Much, much better response. The smoke cloud is also HUGE!!! Very cool. I turned the comp on 2x2 and proceeded to drive around. Once again, throttle response was vastly improved as was power delivery. Now, I have no clue what this is gonna do to my mileage nor do I care at this point in time. I'm having to much fun. I just thought I'd share this with yall.
First notice is that I can floor it in park and a huge cloud of smoke comes out. Cool. So I put it in gear and proceed from a stop. First thing I notice is how responsive the truck is. Much more responsive than with the comp on 5x5 and the map plugged in. Smoke is also very easily produced. That's cool. I stomp on it from a stop light. BIG DIFFERENCE!! The defueling that I used to experience so badly from a stop on 5x5 is now gone. I would defuel so bad in first gear I could only see about 20 psi of boost. Now I'm seeing roughly 25-28psi. So first gear actually moves you now. Once you hit second it's an animal. Much, much better response. The smoke cloud is also HUGE!!! Very cool. I turned the comp on 2x2 and proceeded to drive around. Once again, throttle response was vastly improved as was power delivery. Now, I have no clue what this is gonna do to my mileage nor do I care at this point in time. I'm having to much fun. I just thought I'd share this with yall.
#2
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blue,
look behind you thats money and power going up in smoke would like to see some numbers on hp/tq with that mod
ps what numbers did you see without your comp tap
bad 1 ton
look behind you thats money and power going up in smoke would like to see some numbers on hp/tq with that mod
ps what numbers did you see without your comp tap
bad 1 ton
#3
With my comp untapped and stock turbo I saw 260/600 but it wasn't a good day to dyno. 115* in the shop. I shoulda been around 300hp. Once the wire was tapped and I had the KSB-1 on, I did 371hp. I've got plenty of air for this combo. At 117mph sustained I can only hit 1250* or so EGT's with no smoke at full boost so I'm burning all of the fuel completely which is what I like. I'm not expecting any extra power from this mod, just responsiveness off the line. When the map was plugged in, I would bog real bad coming off the line. Now it comes off very hot.
#5
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That is interesting Blue, I noticed much better pull after I plugged in the Comp to the MAP sensor. I dynoed my sig with the Comp unplugged, and I did not find it until I was running the big line kit. Now it runs harder than it did before, and I am smoking much more.
#6
Mine is still plugged into the factory map sensor harness, but it's not plugged into the map sensor itself. You know how the factory harness attaches to the comp and then the comp goes into the map sensor itself? All I did was remove the comp from the map sensor itself but left the factory harness plugged into the comp. Make sense?
bad 1 ton, call up DTT and ask for Stephan. Tell him you want a valve body that will hold a comp and 275 injectors and he'll build it for ya and it will hold it.
bad 1 ton, call up DTT and ask for Stephan. Tell him you want a valve body that will hold a comp and 275 injectors and he'll build it for ya and it will hold it.
#7
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hey blue, who gave ya the idea? the smoke is huge isnt it? ive been runnin mine unpluged for quite a while now. the only downside is that when its cold, if you get into it hard itll spudder a little. other than that, heck with the fuel milage, its more than worth it!
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#9
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ain't the smoke great, on the trucks I unplugged I always noticed a harder pull down low, & the smoke still clears up nicely, w/out huge sticks anyway, I'd never plug the map up if I had an overvalved truck & the comp, seems to me like it makes them pull more like a 12 valve at low boost, I really like the extra power down low, just my own personal opinion, Dusty
p.s. blackdiesel, I see you're still enjoying urs unplugged
p.s. blackdiesel, I see you're still enjoying urs unplugged
#10
That's the main reason I'm thinking about leaving mine unplugged is for the bottom end. It's a lot smoother and stronger than with it plugged in. I wonder what this would do on a truck with a catcher?
#11
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I just unplugged my MAP and I litteraly can not see behind me. With my 125 sticks and that i will for sure get into alot of trouble.
#13
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Originally Posted by BigBlue
The reason you can't see behind you is because it's night time you idiot.
#14
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as i told tyler, keep the smoke down or you won't be able to do it in the future. they have restriced the big rigs and we are next.
remember we are like muscle cars of the 60's. the EPA killed them and they can kill these trucks just as quick
remember we are like muscle cars of the 60's. the EPA killed them and they can kill these trucks just as quick
#15
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This should work with my VA box right? I have been thinking about unplugging it for a while, but I have never heard about an actual improvement. I'll let everyone know tomorrow if it works or if I had to use the scanner to clear the codes