I've been running your APR X1 for several months now and would like to offer my customer feedback on the unit. The first thing I discovered is how well the AFR/O2 sensor feedback AFR control works. The second thing I discovered is how different the MAF signal slope and MAF transfer function are between the 4.0L Toyota truck engine MAF/intake (that the X1 comes calibrated for) and the Scion TC/XB 2AZ-FE MAF/intake. While using a highly accurate MAF sensor to measure air flow is a great idea, it doesn't work so well when the X1 is programmed for one MAF sensor/intake but connected to a different MAF sensor/intake sending a different signal output for a given volume of air flow. It leads to airflow measurement and load calculation error by both the X1 and ECU.

Sure, you can adjust the oem/installed injector sizes, maf adjust table and/or injector adjustment table (as suggested by Dezod) to compensate for the MAF air flow measurement error but it's very tedious and IMO a "hack" work-around compared to how the X1 was designed to work seamlessly with the 4.0L Toyota engines. Although I have a 67mm ID intake pipe, I have to set the X1 MAF ID to 73mm to prevent the X1 from sending a grossly inflated MAF signal to the ECU (MAF transfer function error). Of course doing this also inflates the X1 and ECU airflow and load readings resulting in inaccurate airflow and load measurement by both the X1 and ECU. I have a AT and very often it "sticks" in 1st gear far longer than it should due to the ECU miscalculating engine load. This problem occurs with the X1 MAF ID set anywhere from 65mm to 73mm. This problem never occured without the X1 (FIC or ECU only).

After many hours on the phone with APR the consensus was that if I want my X1 to function as it does with the 4.0L engine I need to send my existing intake piping and MAF to APR for bench-flow testing and pay them to re-calibrate the X1's MAF signal slope and transfer function for my 2AZ-FE setup. APR used to include these essential MAF calibrations in the software front-end but no longer do since they never really intended the X1 for use on other vehicles.

Bottom line is that the APR X1 is pretty much "self-tuning" (as described by Gadget at URD) when used on the 4.0L Toyota engines but in my experience requires as much tuning as any piggyback when used on the 2AZ-FE. Although the X1 is a very capable and competent engine management system, it's important to understand before plunking down $2000 of your hard-earned dollars on one that it requires a lot of tuning, the software and data logging are much harder to use than the FIC and very few tuners have any experience with this unit. For instance, URD is not far from me and they sell lots of APR X1s for 4.0L Toyota trucks. When I asked them about tuning my X1 their reply was "Why? the X1 doesn't need it, it's "self-tuning"". Yeah, I suppose it would be if I somehow adapted a 4.0L truck intake and MAF sensor to my Scion XB turbo setup. Caveat emptor.

 

Wow...that was a lot of information to digest. Is there a less hassle free solution/work around for this. Like what is the best avenue to tackle this? Is this one of those situations where the management acts crazy because the vehicle is Automatic?

 

The X1 has enough tuning capabilities to compensate for the MAF airflow measurement error inherent due to it being programmed for a different MAF and intake system than the Scion TC/XB. My complaint is that I bought the X1 expecting that if I set the primary scalar settings (MAF-ID, oem/installed INJ size, oem/installed INJ voltage offest) correctly, it would compensate for any remaining minor deviations using it's oem AFR sensor feedback. What I found instead is that the inherent airflow measurement error necessitates tweaking hundreds of individual table cells to acheive the desired results. I wanted something easier to tune than the FIC and got something much harder to tune, albeit arguably with better end results.

In short, the X1 needs to know that a 1V MAF signal = x airflow volume and that a 4V MAF signal = y airflow volume but it only knows the correct values for the 4.0L engine intake/MAF setup for which it is programmed. The simplest solution therefore is probably to utilize a MAF/intake system that very closely mirrors the MAF signal to airflow readings of the 4.0L engine. When I bought the X1 it was explained to me that all I had to do was change the MAF-ID to match my MAF intake pipe ID. This has proven to be far from the case. In fact doing so made my car so undriveable that I had to pull the X1 and send it back for testing as it appeared that the X1 was not working or that the harness had a faulty connection. It turned out that setting the MAF-ID to 67mm caused the X1 to tell the ECU that the airflow was ~25% greater than actual. Setting the MAF-ID to 73mm reduces this "transfer function" error greatly but results in both the X1 and ECU reading inflated airflow from the MAF.

IMO the shifting problems with my AT are an effect of the airflow/load miscalculations and not in any way a cause of them.

 

^^I'm still learning the tuning aspects of it all. Good info.

 

real feedback 4tw.

Fred, I know you spoke alot with brad with some of the issues. You should really of tried the combo were using on his car.

The Greddy/Split second box.

Hes still in love! o issues! and set your maf clamp and go! We have even figured out knock control. incresed revlimit on 05 06 07 08-09 Those years all have different ecu's. You can adjust fuel/timing based on air temp or water temp.

But something tells me. You dont wanna spend more money on this! Hopefully the calibration of maf is not alot!

I wish you luck buddy! On the bright side. Nothings ever perfect off the start!

 

Did you pick up an X1, rhythmn? I'm trying to learn as much as I can about this EMU since I'm heavily thinking of investing in one. Good info ScionFred!

 

Naw, I do just fine with an Ultimate. After that I probably will go Hydra or Haltech.

 

Brett, there are quite a few other customers other than you that are having excellent experiences with the X1, however I am afraid you may not be having them. I am always willing to help you in a way possible, but you never asked!

This unit is far from a hack at all actually and those whom have it on their car; have it running well. The system (like any other engine management system) will need tweaking to your individual setup. We have a few S1s running this with no issues. We have a few custom turbo tC setups running this as well. Bdyer666 has a custom setup and is working his way through tuning it right now with good success on his own.

With respect to the xB2, I have one successfully running on our shop STOCK xB2. The vehicle runs smoother than stock, has a CRAZY flat TQ curve, revs to 7K and will break traction in 1st, chirp into 2nd and if I am lucky and really pushing her hard 3rd as well. I am running a stock airbox with a MAF ID in the cal of 73mm (if I recall)

The bottom line is, it requires tuning like everything else. The simple function of the MAF ID size change alters the OEM Bernoli equation, which in fact alters the entire OEM sensing of load as a whole. You are now experiencing that first hand. For some more insight on this phenom, please read this:
http://aprpower.com/pdfs/APR%20Intro...iciency_00.pdf

^^Now for granted a LOT of the math in there is over plenty of people's math, but if you read the text material, a lot of the theory will make sense.

Lastly, the X1 is not completely self tuning. Once the proper injector size is achieved and the "injadj" table is done, the unit is VERY accurate, responds well and is almost self learning in the fact that it will make corrections for your "injadj" table being off by up to +/-25% with respect to fuel delivery when in FFM

Feel free to send me a datalog and cal file to view and let me see what you have going on there.

Just note, this unit is like a standalone more than like a piggyback in the fashion that garbage or half-arsed in = garbage out. I can prove that time and time again with simple cal changes on mine. You see first hand loss in power and drive ability.

Also, recall that your intake setup is very unique as well. As it transitions right before the MAF in size piping from 2.75" to 2.5" AND you have a silicone coupler inserted inside the pipe to "help" (in your words) transition the air flow easier.

 

Sorry, had to change comps....

Matter of fact Brett, I'd be happy to take a crack at the X1 on your xB2. Come to Buffalo or pay for me to come to MD.

In fact, for starters, here is my 90% tuned N/A xB map. Feel free to take a look at it. Shred it, do what you'd like with it. Notice the injadj table and all are used. Note my MAF size as well.

Stock 2008 xB2 5 speed

I still need to work on REAL low load, heavy throttle and from 6K-7K at WOT

Fuel feedback at WOT in 3rd and 4th gears is between -3 and 0%. The AFR control is unreal.

 

I personally think this entire problem resides in the intake air pipe construction. You used to see this problem with Subarus constantly which use the same type of hot wire MAF sensor. When the intake was changed and size changed it would cause a difference in velocity thus creating a difference in air flow readings. Some cheap filters used to cause turbulence in the intake when transitioning from part throttle to WOT creating erroneous readings from the MAF and thus really poor driveability. As soon as a proper intake was installed, voila, problems solved.

I personally think that your intake is the problem. Even with that coupler in there you could be creating a lot of turbulence before a sensor that needs air to travel straight through it. Logically speaking it's the only piece of the puzzle that is unique to you and you alone and you are the only one having issues.

Why not cut that welded in section out of the end of the intake and just get the proper size filter, as well as a longer one that can take in a little more air for safety sake. You are creating a large column of air with that super long intake and if the filter isn't able to flow enough it will become a restriction. Also check to make sure your welds don't have pin holes near the MAF causing erroneous readings as well.

Good luck.

 

I am having great results with my apr my maf reading is dead on the money. I wont lie to ya i have asked paul for help quite a few times and of course with out question he did and he was able to get me in the right directions over email in like 5 minutes. but that had to do with transition from the stock ecu to the apr takin over and then he through in fixin my timing map a smidge well actually alot cause i neglected it fiddlin with the inj adj table. The inj adj table does take some time to get all the points zeroed in but that is tuning for you sometimes it takes multiple test drives and tuning changes to get it where you like it and in order to know your tuning is good you have to watch the FTs on every load point which takes time. But once you take the time to do this the thing is smooth like silk. Ive been fiddlin with it for awhile and i still will find random load points that need adjusted. All in all i really think this ecu is the new hotness!

 

I am glad I was able to help Brandon. Do you have any pics of your custom setup to share buddy?

 

i get off at 5 will snap some and postem

 

Have to agree here. Not liking the pipe jammed into another one and welded right before the MAF. As Fred has stated its super sensitive while making the piping I would try and make the MAF have the most consistent readings possible

 

Paul took me for a spin in the Xb2 with the X1 being the only mod roughly a week ago when I went to get tuned; and let me tell you... when Paul shifted into second gear I thought we got rear ended by a truck and ran over a log at the same time. The torque was super impressive even going into third gear threw me back in my seat with a small chirp at the wheels haha. I damn near got my head snapped off my neck. Now I've never driven an Xb2, but since it also has the 2AZFE engine I can compare it to my tC and I don't ever recall my car displaying that kind of torque especially stock.

...Just my experience with the X1 to take or leave

 

paul how would this unit work on my car with e85 im looking for something better then the fic or would you recommend going with the aem ems

 

posted some random picage

 

That Greddy/SS combo sounds great. The SS box addresses the main shortcoming of the GEMU. Despite my disappointment with the X1 on my current setup, I still believe it is a great EM unit provided that the intake/MAF are close enough to it's internal hard-coding. I can have my intake flow bench tested and the X1 re-programmed for it (optimal) or I can make a new intake that more closely matches that used on the 4.0L V6 and oem XB or I can spend a lot of time trying to tune around the airflow measurement inaccuracies. I'm skeptical about the last option for the following reasons:

1) If I set my MafID to the actual 66mm the X1 gets pretty accurate airflow but the hard-programmed transfer function sends a ~25% inflated MAF signal to the ECU. Tried it, doesn't work at all.

2) If I set the MafID to 74mm the X1 and ECU get roughly the same MAF signal but it's inflated by ~10%. Using this now, not bad but not great either. Obviously the ECU pulls more timing and adds extra fuel due to the +10% airflow error.

IMO my problems are primarily caused by running a slightly smaller ID MAF tube. The X1 is programmed for a intake that starts at 100mm and tapers to 74mm before the MAF sensor (which is also quite different from the TC/XB MAF). The X1 transfer function is based on the 4.0L intake/MAF/ECU. The stock TC maf tube is 64mm and the XB's is 71mm. My current plan is to make the straightest, smoothest flowing 3" (74mm ID) intake pipe I can and then tuning around any remaining error. I just don't think I can tune around the problems with my current 66mm intake because of my AT. If I had a MT and the ECU was seeing +10% load, I could tune around that. With an AT that +10% error also affects shifting.

As for spending money, I gave up on frugality $4000 ago. I don't care about the cost any more. I just want this $hit to work right. Thanks mang.

 

Hey Paul, I didn't mean to imply that your X1 is a hack, merely that the method of tuning around the MAF airflow measurement error is a bit of a hack when the X1 is capable of such accuracy when programmed for a specific intake/MAF sensor. You can factually state that I haven't asked you for help recently but not that I "never asked". I stopped asking when you kept suggesting that I refer to your 'tuning guide' that suggests using the INJ adj table to tune when that table has no effect on the airflow/load seen by the ECU. It only alters the amount of fuel added for a given air volume.

I can see how a MafID of 73mm would work with the stock XB's 71mm maf tube. Since the 4.0L uses a 74mm maf tube and the transfer function inflates the ECU's maf signal when MafID is set to less than 74mm, 73mm seems like a good compromise setting for your XB. Too bad it doesn't work with a smaller MAF tube like mine.

I understand how the Bernoulli equation works and that is precisely why the X1 works so well with the 4.0L and not as well with the 2.4L. If the X1 knows that 1V MAF = 10 g/s and that 4V MAF = 150 g/s precisely and it knows exactly what MAF signal the ECU expects at any given airflow volume, it should be "self-tuning" in that all you need to set is the scalar values to maintain the correct Bernoulli equation results. My point is that all the cell by cell table tuning is neccessitated due to MAF signal error caused by running different intakes and MAF sensors that don't match the X1's hard-coded MAF signal slope and transfer function.

I couldn't agree more that "garbage in = garbage out". That very neatly sums up my problem with the X1. Not that it's especially relevant but my intake is actually 2.75" OD with a 3" OD piece welded onto the filter end. The internal transition is very abrupt and turbulence inducing which is why I added that carefully trimmed piece of tight-fitting silicone coupler. It made the transition very smooth by comparison but just to be sure, I removed it weeks ago and if anything it made things worse.

Thanks for the new NA XB calibration but I tried the last one you sent me and it wasn't even close for my setup. I really think that the XB needs a MAF tube between 70 and 75mm to work with the X1's current MAF hard-coding. To that end I plan to make a new 3" intake to get closer to the X1 MAF hard-coding before spending a lot of time tuning. I may well end up making the trip to Buffalo for a tune. I'll be in touch and thanks for your continued help.

 

Well... yes and no. Yes, my intake deviates too far from the 4.0L X1 hard-coding but no, it isn't the only problem. Paul has told me that he's had to alter some of the X1's scalar settings pretty drastically from actual to compensate for MAF signal deviation. I've also seen from his calibrations that he's even added timing to compensate for the ECU pulling it due to falsely exagerated load readings. Even the MafID's currently being used are altered to compensate for MAF signal deviation from the X1's hard-coded MAF signal slope and transfer function.

But... things being what they are, you're correct (IMO). If I want the X1 to work for me in it's current configuration, I need to use a new intake/MAF tube that more closely matches the MAF signal slope and transfer function hard-coded into the X1. IMO anyone planning to use the X1 on a XB2 better plan on using a ~3" intake/MAF tube because 2.75" doesn't work.

I would cut that 3" piece off the end but I strongly feel that the 2.75" maf pipe is too small for the X1's programming and a XB2. Therefore I plan to replace the existing intake tube with a shorter, straighter, smoother 3" intake. My air filter is a AEM dryflow with a velocity stack base, I'll keep that.

Thanks Don.