I completed doing the Throttle Stop Mod as well as another free mod called the Throttle Body bypass mod. The bypass mod I did a while ago and probably doesn't do to much in the way of Seat of the pant's performance gains. I will talk about the Throttle Stop Mod on my 5.3 here.
The Throttle Bodies on our trucks as well as older years only open up to 80% at WOT. This means that when you step on the gas all the way, the Throttle will open up 80%. Generally speaking, ?at idle a throttle plate should be closed or nearly closed. At 50% throttle input the throttle plate should be open 50%. At 100% throttle input the throttle plate should be open 100%.
G.M has designed Our Throttle Bodies to open up a maximum of 80%. One thing that I noticed was that when I accelerated with the pedal 2/3 to the floor, I could push the pedal the additional 1/3 and I would feel no more acceleration difference. This is because, at approx. 2/3 throttle pedal travel the throttle plate is opened as far as it can go (Throttle stop is hitting)
The mod performed removes a few millimeters of the stop on the throttle body and allows the throttle plate to open up to near 100%
In order to do this Mod you need an ATAP which is a computer reader or a Digital Volt meter that reads D.C. I used the volt meter method without a problem. Looking at the Throttle Body from the front, there are 2 sensors with wires on the right side. The lower sensor is the Throttle Position Sensor. This sensor has 3 wires. A grey, a Blue and a Black. I stripped back just enough insulation on the Blue and Black wires to get my test probes clipped on. Blue is + and Black is -.
With the ignition key on engine off, I got a .50 voltage reading. At full throttle position I got a 4.30 volt reading. A maximum voltage to acheive is no more then 4.6 volts. Some will say 4.7 but the majority agree that 4.6 is the safety mark. At about 4.8 volts, the sensor will trigger a code.
Now I began to SLOWLY grind back the Throttle Stop on the Throttle body's left side. Grind a little and check voltage at full throttle pedal position. I used a Dremel which is probably the best method for a controlled grind. It took me about 2 hours of light grinding to acheive 4.6 volts and the Throttle Plate is now at near 90 degrees (100%) at WOT.
Do I notice a Difference ?
The short answer is YES !!
Now when I reach 2/3 throttle and I push the pedal the rest of the way, I do get more response from the engine.
The Throttle Bodies on our trucks as well as older years only open up to 80% at WOT. This means that when you step on the gas all the way, the Throttle will open up 80%. Generally speaking, ?at idle a throttle plate should be closed or nearly closed. At 50% throttle input the throttle plate should be open 50%. At 100% throttle input the throttle plate should be open 100%.
G.M has designed Our Throttle Bodies to open up a maximum of 80%. One thing that I noticed was that when I accelerated with the pedal 2/3 to the floor, I could push the pedal the additional 1/3 and I would feel no more acceleration difference. This is because, at approx. 2/3 throttle pedal travel the throttle plate is opened as far as it can go (Throttle stop is hitting)
The mod performed removes a few millimeters of the stop on the throttle body and allows the throttle plate to open up to near 100%
In order to do this Mod you need an ATAP which is a computer reader or a Digital Volt meter that reads D.C. I used the volt meter method without a problem. Looking at the Throttle Body from the front, there are 2 sensors with wires on the right side. The lower sensor is the Throttle Position Sensor. This sensor has 3 wires. A grey, a Blue and a Black. I stripped back just enough insulation on the Blue and Black wires to get my test probes clipped on. Blue is + and Black is -.
With the ignition key on engine off, I got a .50 voltage reading. At full throttle position I got a 4.30 volt reading. A maximum voltage to acheive is no more then 4.6 volts. Some will say 4.7 but the majority agree that 4.6 is the safety mark. At about 4.8 volts, the sensor will trigger a code.
Now I began to SLOWLY grind back the Throttle Stop on the Throttle body's left side. Grind a little and check voltage at full throttle pedal position. I used a Dremel which is probably the best method for a controlled grind. It took me about 2 hours of light grinding to acheive 4.6 volts and the Throttle Plate is now at near 90 degrees (100%) at WOT.
Do I notice a Difference ?
The short answer is YES !!
Now when I reach 2/3 throttle and I push the pedal the rest of the way, I do get more response from the engine.
great instructions 
