How-To Control Boost with the stock boost solenoid and a custom pill

[Evo_Kid]

This how-to will make it so you can run anywhere from wastegate boost (12-14lbs) to race gas boost (25+lbs) using the stock boost control solenoid, stock ECU and ECUflash.

DISCLAIMER

This mod will change boost characteristics drastically. Do at your own risk.

You will need:

Tools
3/8 ratchet
10mm socket
phillips screwdriver
regular (flat) screwdriver
regular pliers
needle nose pliers
hack saw/power wire cutters

From the store(s):

5/32 (4mm) vacuum hose (1 ft)
3/16 aluminum rod (1 ft)
one or more of the following drill bits (more on this later)
Wire gauge size drill bits
#60 / 0.0400in. / 1.02mm
#57 / 0.0430in. / 1.09mm


Step 1
Remove the two (2) clips holding the ram air duct on.

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Step 2
Undo four (4) clamps holding air box lid on. Remover lid and air filter.

Step 3
Remove two (2) 100mm bolts that secure the air box.

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Step 4
Loosen the clamp where the intake tube meets the air box/MAF.

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Step 5
Remove the air box, unplugging the MAF sensor plug and unclipping the wire holder in the process.

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[Evo_Kid]

Step 6
Take a look at the boost lines and get familiar with the configuration.

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Step 7
Loosen DV/BOV

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Step 8
Remove breather hose near DV/BV (behind it).

Step 9
Loosen the clamp where the intake tube meets the turbo

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Step 10
Remove intake tube, disconnecting the vacuum hose from the boost solenoid in the process.

Step 11
Using the needle nose pliers, pinch the clamp holding the vacuum line going to the turbo outlet pipe (at the turbo outlet pipe, not the tee) and slid the clamp up the line, then pull the line off.

Step 12
Using the regular pliers, pinch the clamp holding the vacuum line going to the wastegate (at the tee, not at the wastegate) and slid the clamp up the line, then pull the line off.

Step 13
Take the short line going from the tee to the turbo off the tee.

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[Evo_Kid]

Step 14
Take the aluminum rod and cut off a 5/16in (8mm) section.

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Step 15
Now for the drill bit selection.

If you just want to make enough head room for pump gas boost (20-23lbs), use the #57 drill bit.

If you want to be able to run pump gas boost and race gas boost (25+lbs), use the #60 drill bit.

You can also experiment with other sizes. Just remember that the high # of the drill bit means a smaller hole, and in turn, higher boost.

Step 16
Using a pair of pliers and friend (or a vise) to hold it, drill a hole though the small section of aluminum rod. Try and get the hole as strait and center as you can.

Step 17
Cut a piece of the vacuum line about the same length of the stock piece. Using a 3mm allen wrench (or similar item), push the newly drilled small section of aluminum rod into the vacuum line, to the middle.

Step 18
Using the new vacuum line and modified pill to replace the stock piece going from the tee to the turbo, put everything back together and go get your laptop and Tactrix cable.

[Evo_Kid]

DONT DRIVE UNTIL YOU HAVE ATLEAST LOWERED THE WGDC TO 50

Step 19 - Tuning
The following maps will need to be changed for basic boost control

Max WGDG/Basline WGDC (NOTE: map will be titled MAX WGDC or Baseline WGDC, based on what definitions your using. They are the same map.)

Boost Desired Engine Load

Boost Control Load Offset

Turbo Boost Error Correction

Boost Limit - This is the famous "Boost/fuel Cut". Set this about 20 higher then your max load.


PROCESS
***When taking the car out for the first test drive, roll on to boost SLOWLY and constantly monitor boost. If it starts to boost more then a safe amount for your octane and tune, LET OFF THE GAS.


Zero out the right side of the "Turbo Boost Error Correction" map. (keep a copy of the stock settings somewhere)

Then use the "Max WGDG/Basline WGDC" to get your desired boost curve in 3rd gear.

**Here is an example
RPM - WG duty
2000 - 70
2500 - 60
3000 - 50
3500 - 50
4000 - 50
4500 - 50
5000 - 55
5500 - 55
6000 - 60
6500 - 65
7000 - 70

After you have your desired boost curve, log your load (preferable 2byte load) in 3rd gear from 2500-7500RPM.

Set "Boost Control Load Offset" and the "Boost Desired Engine Load" so when they are added together, they add up to the load in your log (@ the same RPM point). ie if you logged 240 load @ 3500RPM, then the "Boost Control Load Offset" would be 100 and the "Boost Desired Engine Load" to be 140 @ 3500RPM.

After you have your "Boost Desired Engine Load" completely filled out, using your logs for load amounts, then re-enter the stock setting on the right side of the "Turbo Boost Error Correction" map (Stock setting can work, but you may have to tune this map)

It will take some tuning to get everything perfect. Log Load, boost, WGDC, Load Error and WGDC Correction and make correction based on those.

Also, here is a great description on how the error correction work. Thanks mrfred
*BDEL=Boost Desired Engine Load

The "Max WGDC" table is poorly named. It should be called "Baseline WGDC" table. When you are cruising, the car is at 0% WGDC (at least that's what EvoScan says), and when you stomp on the gas, the ECU looks at the engine RPM, then goes to the Baseline WGDC table, reads the WGDC number, and applies that value to the BCS. At that point, the ECU then starts comparing the actual load to the target load (BDEL + boost offset) about once every 0.4 seconds. If the actual load matches the target load, then the ECU continues to follow the WGDC value (vs RPM) in the baseline WGDC table. However, if the ECU sees a discrepancy between actual and target load, then it can/will apply a correction to the WGDC. The amount of correction depends on the values in the boost error correction table. The correction is simply to raise or lower the entire Baseline WGDC curve. So after the correction is applied, the ECU follows the raised/lowered curve. It checks again 0.4 seconds later, and if necessary, raises or lowers the curve again. This is why the correction table isn't a function of RPM. The graph shows the behavior well. The blue arrows show when corrections are made, and its apparent that the ECU is simply raising/lowering the baseline WGDC curve.

[Evo_Kid]

Here are link to "mods" that can be done to make ECU boost better and easier to tune

Fine tuning Load based boost control to prevent weather based boost variation by mrfred
http://forums.evolutionm.net/ecuflas...trol-mods.html

Direct ECU boost control by mrfred
http://forums.evolutionm.net/ecuflas...t-control.html