DIY: AVC-R set up

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idahotuner
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Joined: Thu Jun 28, 2007 7:11 am
Car: 2012 ram 2500 6.7 cummins, 93 Sileighty and 93 civic hatch, polaris ranger 2011
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I found this while searching out to set up mine. and thought it be useful for people on here too.

Welcome,

The Apexi AVCR is one of the best if not the best electronic boost controller in the world. It is liked and disliked for many reasons but the one thing the unit does well is hold boost stable and produce less spiking than nearly any other controller on the market.

In this guide, i will show you how to set up all the different parameters of the AVCR. From the initial boost setting through to the final start duty trimming of the boost maps.

Start up check;

Before we go into the setting up mode there is a couple of things which we must check to make sure the unit is set up correctly for the manual adjustment mode we are abnout to use. First off I would advise we go now and turn OFF the self learn mode for each gear. The AVCR uses a unique fuzzy logic self learning mode that can adjust the boost to prevent spikes etc. but i have found that it is very inconsistent and actually makes the car ramp up boost a LOT slower than what we can acheive by manually setting the controller.

Go into the the main menu:



Select setting A first then once we have done A go on to setting B.Now move down the menu until we highlight the Learn-Gear mode and press the next button. Now we can go along and make sure each gear is marked with an X, it should look like the following screenshot;



This will disable the self learn for al the gears and allow us to fully customize the adjustments to acheive the fastest ramp up and most stable boost control the unit can offer.

Secondly we need to make sure that when the boost controller was installed that the purple wire from the AVCR unit was connected to the RPM signal wire from the cars main ECU. This is a must if we are going to use the RPM specific adjustments and to get an accurate measure on how the boost is sitting at certain RPM points in the monitor mode.

How to check the boost level after adjustments are made;

Now i will show you how to check your boost setting the correct way. Any adjustments made to the AVCR sgould be checked by using this method. This method gives you an accurate true reading of your full boost under full load. Boost should not be checked any other way in my opinion. If you have access to a dyno i would recommend this is done on the dyno but it can be done on the street (*note, the QLD street scene staff take no responsibility for any misuse on the street and any fines/loss of license caused by breaking the state/federal laws in your local area.)

Once you have the boost and duty set ( we will learn how to do this later in the guide ) get the car into 4th gear at around 60km/h at a cruising pace, then go full throttle and hold it full until around 6000rpm. Monitor the boost on the AVCR or a boost gauge and see what the boost reached. If you have a passenger that can watch it more closely to check if there are any spikes etc. at a certain rpm point. This is very important when setting the start duty and RPM specific boost levels later in the guide.

I like to use the following monitor mode so i can keep an eye on boost at certain rpm points.

Each time you make an adjustment to the AVCR i would recommend checking the boost with the above method. This way you can make sure that you have made the correct adjustment and not have the car overboost later on if left unchecked.

Setting the basics up;

The initial set up requires you to go into the ETC. menu on the main menu screen. In here we can adjust the Car select, Screen brightness etc. I will leave this menu and setting up to Apexi themselves as they have covered it very well in the AVCR manual. If you do not have a copy of the manual check it out in PDF format here: http://www.apexi-usa.com/pdfInstallation/45.pdf

Setting the initial boost setting;

Once we have the car specific settings sorted out we can start to adjust the boost nice and accurate. We will start off with the initial setting.



In this menu select either setting A or setting B to adjust either of the 2 boost maps. Setting OFF means the car will run on standard wastegate spring pressure boost. Which in most cars is around 7-10psi ( 0.5-0.7 bar )

Once you have selected the map you would like to adjust press the next button and we will move onto the Map A or B setting screen. Select Boost/duty #1 in the menu and press the next button. Now we can adjust the initial boost/duty level.



Highlight the Boost or Duty setting and press > to highlight the setting. Pressing the up or down button we can adjust the boost and duty cycle level accordingly. Every different engine and turbo combination will have a different duty cycle setting required to acheive the desired boost level. I would recommend starting with a setting of around 40% duty for boost levels of 0.7 bar and then going and checking the boost with the method at the start of the guide. If the boost is to low then raise the duty cycle a couple of % at a time and repeat the checking procedure. If the boost is to high and it overshoots the desired boost level then lower the duty a couple of % at a time accordingly. This may take some time to get accurate but it is a must to acheive stable boost.Once we have this set and the boost is relatively stable we can move on to the RPM specific boost levels.

Setting the RPM specific boost levels;



First we need to set the NE points ( specific RPM points that the duty cycle can be adjusted ) I would recommend the settings as follows for use on an SR20DET engine;

1. 1500rpm2. 2500rpm3. 3000rpm4. 3500rpm5. 4000rpm6. 5000rpm7. 6000rpm8. 7000rpm

For different engines you can try different settings, for the SR20DET using a T28 turbo these settings provide the most adjustment where the main boost ramp up takes place.

Once we have the NE points set we need to take the car out and do a boost level check. Making sure we monitor the boost all the way through the RPM`s to see if there is any certain point at which the boost drops off or overshoots. Take note of these points if there are any and we can move on to the setting mode, which is located in the Boost/duty setting menu by highlighting the duty cycle and pressing the next button.



Now we can go along the graph using the arrow buttons and raise or lower the boost at any points that had troubles. In most cases turbos that run internal wastegates the boost tends to taper off slightly at the higher end of the RPM scale. Raising the duty slightly at 6000rpm+ can most of the time eliminate this.

Setting the AVCR to ramp the boost up as fast as possible;

Another great aspect of the AVCR that can be acheived from the RPM specific adjustment is the fact that we can keep the wastegate closed 100% at early RPMs to help bring on the boost a lot sooner. This is a little bit complicated to get 100% accurate so we will just set this at an average ( safe ) setting. Go and check your boost level again, and this time monitor when the AVCR comes onto full boost ( most cars with smaller turbos should acheive this around 3000rpm ) basicaly when we have learnt where full boost occurs on the RPM scale, simply take 500rpm off this number and we get an RPM number that i like to call a SAFE rpm zone. A area of the RPM where the turbo isnt ramping up very hard and an area that can withstand the wastegate being 100% closed and not getting any spikes from it.

Now we can go along in the RPM/duty adjustment graph and take the lower RPM points including this SAFE RPM zone and below up to 90% duty cycle.Should look like the graph below; ( graph is only an example, different engines will vary ).



Now when we check the boost level it should be very stable if not perfect accross the entire RPM range. Only trouble is, this is all good but it is only for 4th gear. The car will have varying boost in every gear so this is where we come to adjusting the Start Duty.

Adjusting the start duty for each gear;



This is more of a fine tuning tool but is an important one at that. Before we go on make sure that the gear judge in the ETC menu has been set up correctly for the AVCR to determine which gear the car is in. Refer to the manual link below for the correct procedure of setting this up. http://www.apexi-usa.com/pdfInstallation/45.pdf

First off we have to go and check the boost for each gear. We will have to do this differently now as we have 4th gear set pretty good at this stage. I like to start off doing 1st gear and then going up through the gears as i get each one set correctly. Start off at low RPM`s ( around 1500-2000 ) in each gear and go to full throttle up to about 6000 rpm and monitor the boost closely the whole time watching for spikes or drop offs. If you find it spikes or drops off in a particular gear, simply raise or lower the duty cycle accordingly until you can smash through the gears at wide open throttle and the boost stays consistent throughout the rev range.

If the car has wheelspin trouble in 1st gear we can lower the duty cycle down for this particular gear until we eliminate wheelspin. If you love the wheelspin then great...enjoy it!!

Setting up the feedback setting;



The feedback setting is one of the last settings we need to use and is only needed if after all the above adjustments are made and boost is still a bit inconsistant and unstable. Basically the higher the feedback setting is for a particular gear, the more the AVCR will correct itself to acheive the boost setting inputted. I would not recommend a setting higher than around 6-7 as any higher than this the car can tend to feel a bit jumpy, as the AVCR will sometimes over correct itself and make itself unstable in the process.

Using the Self Learn mode

If you decide that the manual set up mode is a pain in the a$$ and you want to use an easier method than the self learn mode works ok, It is far from accurate most of the time and unless your wastegate is a good one and if you havent got a perfect leak free boost system ( intercooler and piping/plenum ) i dont recommend it.

To set this you will need to make sure first off that the target boost pressure is very close to the perfect or esle the AVCR will not begin self learning as a safety feature. You will need to go into the set up menu for the self learn and make sure it is enabled for the gears you want to use it for.



Make sure you have a "O" in the gears you want it turned ON and an "X" in the gears you want it OFF.

Now go out and set the initial boost like described earlier in this guide, now we have to make sure we are almost spot on with our target boost, as the AVCR will not self learn if it is not within about 0.2 bar of the target boost.

Once you have this you need to do a few runs at above 85% throttle out to redline, if the AVCR see`s that the target boost pressure is close enough for safety it will begin self learning. Self learing can be seen as *** in thefollowing screen beside duty: ( Note: when setting the duty set it at the below screen and DO NOT set any of the individual RPM duty cycle points until it has self learnt, if you do it will bring up the *** beside the duty and you will not be able to determine whether ot not the AVCR is actually self learning or not. By setting the duty as a whole number like 40% in the following screen, as soon as the AVCR begins self learning it will replace the 40% with the *** if it does not do this then the boost pressure is either overshooting or not reaching the target boost setting )



Once it begins self learning it will adjust the rpm specific boost levels based on feedback from itself, much the same as we set it in manual setting mode. The AVCR will not set the first couple of NE points ( 1500-2500rpm ) to 90% on its own, you can actually use self learn mode to get the higher rpm settings correct then go and turn the self learn mode OFF and raise the lower NE points manually to 90% to get both the ease of the self learn set up and the response from a bit of manual setting.

That pretty much wraps it up. It is a time consuming process to set this boost controller up but it is well worth it in the end.

Original version can be found here.http://www.nissansilvia.com/fo...67038


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