NGK AFX vs. AEM 30-0300 CAN Comparison

[LSxpwrdZ]

Oh, that one is easy. It is easily +/- 1% with the several test gasses that I used on the test bench. Slightly more accurate than the ECM/NGK unit that I tested ( Powerdex ).

BUT, the test was performed at atmospheric pressure ( 0psig ). And, I , now, know that the Powerdex was expecting the test gas at ~1.5psi ( 0.1bar ). So, they may be equal, overall. HOWEVER, IF YOU DO A FREE-AIR CAL AT ATMOSPHERIC PRESSURE, YOU GET THE SAME ORIGINAL ERROR!!!

This is one of those cases of chasing the 4th digit.

As for time-skewing the data due to Windows timing. When using CAN data the MPVI, all of the data is collected IN the MPVI, then sent, together, over USB. So, it is properly correlated, at least to itself.

The problem is with USB/Serial ports. They take a separate path from the MVPI data. And that data has an unknown time skew, as compared to the MPVI data. This is PROBABLY not a big issue because serial data-rates are generally pretty low. ( in the 10Hz / 100ms range ). So, 20ms-50ms of skew isn't "that bad".

But, it is still an issue when looking at what I call "cell velocity". "Cell velocity" is the rate at which the RPM and MAP readings move through VE table cells. i.e. During dynamic events, the VE cell may change 30 times in a second ( 33ms per cell change ). So, 50ms of data skew means that the wideband data could be 1 or 2 cells off, from where it SHOULD be applied. Another 100ms of latency makes it even worse.

This kind of skew is a big part of what makes tuning an art. Knowing how to read between the lines.

If the wideband data always wound up in the right VE cell, anybody could tune

Thats the response I was looking for! Especially the last part! Interpretation and understanding of the data and it's limits is a huge part! As cheap as they are I'm going to look at the 30-0300 just to see how well it works.

With the serial communication issue that the older non-CAN car's can have it'd be nice if HP Tuners would release a new cable that had a serial data input on it itself to interpret/integrate the data into the main data stream going into the computer which "should" eliminate those windows issues.

[gmtech16450yz]

Now THIS is a discussion!!!

This kind of skew is a big part of what makes tuning an art. Knowing how to read between the lines.

If the wideband data always wound up in the right VE cell, anybody could tune

You NAILED it right there Mike. That's why I mentioned that I spend more time looking at chart traces than looking at histogram values. I prefer to "see" exactly when these transient changes are happening, rather than relying on the value in a histogram cell to be correct. Maybe it's because I'm used to seeing data from slow widebands that the histogram data can't be trusted, exactly like you're saying. THAT'S why I've said that since tuning with the AEM 30-0300, you CAN actually use histogram data and simply copy/paste your fueling changes. So yeah, I truly believe there will be MANY more successful "tuners" once these CAN based, fast and plenty accurate widebands become common. It's far less "art" like you said, and way more "copy paste" tuning. Anybody can copy/paste. I don't really care that much about the details, I see the end results. Guys simply won't need to know as much or be as talented in the "art" of tuning to get good results with these new widebands. That's the real world side I'm seeing.

Oh BTW, Ron Patrick is a very good friend of a friend. I was actually going to work for Ron at ECM awhile back. My friend is the one that did all the welding on Ron's Jet powered VW. He knows both of us very well and tried to get us to work together. I did actually do some work on one of Ron's cars, an E85 converted LNF Cobalt SS. Unfortunately, when my friend was trying to get me and Ron working together it was when I was thinking about quiting my dealership job. I ended up not leaving my dealership job,my boss and owner threw me a bunch of money to stay. lol. So I never did go to work with Ron at his company, but I know my buddy would love to see us both working there! Small world huh? Oh and he's kind of a kooky guy.

[dr.mike]

With the serial communication issue that the older non-CAN car's can have it'd be nice if HP Tuners would release a new cable that had a serial data input on it itself to interpret/integrate the data into the main data stream going into the computer which "should" eliminate those windows issues.

That has been one of the advantages of using teh MPVI with the 30-0300 w/ the OBDII re-flash. The MVPI will record CAN data ( if present ) even on pre-CANBus cars. So, everything stays synched. You can, if you have that kind f free time on your hands, connect the MPVI to nothing but the 30-0300 and log just its output, alone.

This ability seems to be unique to the MPVI/30-0300 ( come 30-0333 ) combination of devices.

[gmtech16450yz]

Thats the response I was looking for! Especially the last part! Interpretation and understanding of the data and it's limits is a huge part! As cheap as they are I'm going to look at the 30-0300 just to see how well it works.

With the serial communication issue that the older non-CAN car's can have it'd be nice if HP Tuners would release a new cable that had a serial data input on it itself to interpret/integrate the data into the main data stream going into the computer which "should" eliminate those windows issues.

That last line was amazing wasn't it? You guys are all hella smart. I like having a discussion with hella smart guys!!! Thanks for spending the time to discuss! I know I learned a few new things. Oh and James you mentioned having multiple widebands. I don't have one in every cylinder but I do have two of the 30-0300's in the same spots in both manifolds in my LSA. They track damn near identically. I really am impressed by the AEM 30-0300's. I know AEM isn't known for the highest quality stuff, but I don't like to stereotype brands like that. After all, we could say that GM has made some total cr@p cars, and still is. But they also made stuff like the ZR1. So saying GM makes garbage just because they made stuff like the Pontiac Aztek is kind of ignorant in my opinion. (NOT saying you said or think that, it was just one of the common threads in this discussion.) There were a few guys that simply ruled out ANYTHING from AEM just because of the brand name. You just can't do that anymore. Brands can make garbage andstill hit home runs occasionally. Happens all the time.

[LSxpwrdZ]

That has been one of the advantages of using teh MPVI with the 30-0300 w/ the OBDII re-flash. The MVPI will record CAN data ( if present ) even on pre-CANBus cars. So, everything stays synched. You can, if you have that kind f free time on your hands, connect the MPVI to nothing but the 30-0300 and log just its output, alone.

This ability seems to be unique to the MPVI/30-0300 ( come 30-0333 ) combination of devices.

Oh interesting... gets better and better I guess haha.

That last line was amazing wasn't it? You guys are all hella smart. I like having a discussion with hella smart guys!!! Thanks for spending the time to discuss! I know I learned a few new things. Oh and James you mentioned having multiple widebands. I don't have one in every cylinder but I do have two of the 30-0300's in the same spots in both manifolds in my LSA. They track damn near identically. I really am impressed by the AEM 30-0300's. I know AEM isn't known for the highest quality stuff, but I don't like to stereotype brands like that. After all, we could say that GM has made some total cr@p cars, and still is. But they also made stuff like the ZR1. So saying GM makes garbage just because they made stuff like the Pontiac Aztek is kind of ignorant in my opinion. (NOT saying you said or think that, it was just one of the common threads in this discussion.) There were a few guys that simply ruled out ANYTHING from AEM just because of the brand name. You just can't do that anymore. Brands can make garbage and still hit home runs occasionally. Happens all the time.

I can agree with that haha. I knew the LSU4.9 sensor was a good sensor but up until recently ECM hasn't supported that sensor and neither has Haltech (which I use in my race car) with their CAN widebands. They are stuck on the old LSU4.2 sensors. The newer LambdaCAN from ECM supports basically all types of sensors as well as the new AFR500v2 from ECM/Ballenger but no real data has been tested with the Ballenger and the LambdaCAN is just more than my pockets can afford.

[dr.mike]

gmtech16450yz , I am pretty sure that the original intent of widenabd tuning with systems like HPTuners, et al., was to :

1. log the data. keeping a fueling / lambda histogram table.
2. examine the errors between commanded lambda and actual lambda in the tables.
3. apply the error table back to the fueling table
4. repeat.

And, that cycle should converge to a good tune.
But, with all of the errors from analog offsets, latency errors (vs. "cell velocity"), etc. The data never properly "lined up" cell to cell. So, the tune never converged. And you ended up chasing your tail.

That's why i did the mod to the 30-0300. It already had the latency issue kicked. With the OBDII re-flash, I knew I could get rid of the analog offset and data time skew errors.

So... the idea was that the histogram tables would be a real ( usable ) representation of the actual data. Then, one could, as you say, "cut and paste" your way to an ideal tune. Or, at least, as close as possible to that.

As for AEM's quality history. I do not know, as I have never used their older units. ( I previously did all my work with Innovate LC-1s, which have their own unique issues ) But, since I have taken both the 30-0300 and 30-4100/4110 apart, I can tell you that they look to have zero common ancestry. In fact, they seem to have no family resemblance, at all. Probably, closer related to their Infinity ECUs.

[gmtech16450yz]

gmtech16450yz , I am pretty sure that the original intent of widenabd tuning with systems like HPTuners, et al., was to :

1. log the data. keeping a fueling / lambda histogram table.
2. examine the errors between commanded lambda and actual lambda in the tables.
3. apply the error table back to the fueling table
4. repeat.

And, that cycle should converge to a good tune.
But, with all of the errors from analog offsets, latency errors (vs. "cell velocity"), etc. The data never properly "lined up" cell to cell. So, the tune never converged. And you ended up chasing your tail.

That's why i did the mod to the 30-0300. It already had the latency issue kicked. With the OBDII re-flash, I knew I could get rid of the analog offset and data time skew errors.

So... the idea was that the histogram tables would be a real ( usable ) representation of the actual data. Then, one could, as you say, "cut and paste" your way to an ideal tune. Or, at least, as close as possible to that.

Holy f'ing cr@p Mike! Here is a quote from the OP's very first post in this thread...

But now this "ultra accurate" WB reading is showing me my fueling is no longer anywhere near accurate..

With that last statement you just posted, you clearly succeeded in answering the OP's original question, which was the whole point of this thread. You brought us all full circle back to the beginning. And you did it with facts and in a rational, adult, logical and respectful manner. Even when questioned and doubted, you kept posting more information that backed up your opinion. An opinion that was NOT based on emotion or brand bias, but based on your vast experience and knowledge in the actual real world of lab testing and validation of the exact product(s) being discussed. This is obviously your job, your expertise and why the companies that actually produce these products pay you for this data.

For me, the OP's question has been answered definitively. In HIS particular situation, he should trust the AEM. Especially if he's using histogram data only, which I'm betting 90% of "tuners" do. Like you've said, copy and pasting bad data just makes bad tunes. That's not his fault, again, I'm guessing 90% of the guys out there don't realize this can be a problem. I truly believe "tuning" IS an art, and I'm so amazed and happy that you said that. It was a form of validation for me, and I'm sure many others out there that truly understand how this stuff really works. You said it perfectly, if all you have to do is copy histogram data and paste it into your VE or MAF tables, anyone could tune. BINGO! You've just explained why a "tuner" can build a tune, and someone else can look at it and how the engine is actually running and shake his head at what a "hot mess" it is. (OP's exact words btw.)

I'm happy and grateful that you spent the time to clear things up. I'm disappointed that you HAD to spend the time to clear things up. lol. This should have been a discussion and not an emotion based dogpile. Emotion has no place in the work that we all do professionally. If you can't be objective and unbiased, you can't diagnose or test effectively. I have no doubt that the reasons you're good at what you do are those exact traits. I've seen literally hundreds of techs come and go over my 33 years of being a lead dealership tech/foreman/manager. A VERY small percentage can be objective and unbiased and keep emotion out of the data acquisition and final assessment. Thank you VERY much for being unbiased and objective, and pulling it back into an excellent discussion! MUCH respect from this old guy here!

[schpenxel]

Saw the exact same thing in someone's log that I looked at a few minutes ago. They were complaining of no WOT power after a cam swap.. they had no wideband but the NB's went to < 100mV @ WOT after cycling normally prior to going WOT.. so I'd say it's fairly safe to say he's lean as !@#% and needs to stop now before he breaks something. Oh, and he needs to find a new tuner.

Oh, and I love this thread.

[gmtech16450yz]

Saw the exact same thing in someone's log that I looked at a few minutes ago. They were complaining of no WOT power after a cam swap.. they had no wideband but the NB's went to < 100mV @ WOT after cycling normally prior to going WOT.. so I'd say it's fairly safe to say he's lean as !@#% and needs to stop now before he breaks something. Oh, and he needs to find a new tuner.

Oh, and I love this thread.

Threads like this are the reason I hang around places like this. It's too bad it had a rough patch in it, but it made a nice change of direction when Dr. Mike stepped in.

BTW sorry if I was short or not very nice with you, I was a little snippy being at the bottom of the dogpile!

[schpenxel]

It's ok, I'll ban you next time

Just kidding obviously

[gmtech16450yz]

It's ok, I'll ban you next time

Just kidding obviously

haha! I liked that! It wouldn't be the first time. There are 3 Solstice/Sky forums. I pulled off the Trifecta, I've been banned from all 3! I'm actually kind of proud of it since the members and moderators on those forums are insane. Literally insane. That and the average age on those forums is 80. Not kidding. One moderator posted video's of young Korean girls dancing in skimpy outfits, probably posted a couple dozen over a few year period. He's a 55 year old married guy. And those are Auto Guide forums, you can't do that kind of stuff there. But if you say the slightest thing against any of the vendors, even one's that have actually been sued for criminal business practices, he'll ban you. The moderation on those 3 forums has been compared to communist China, rampant censorship for ridiculous reasons. Oh well.

[schpenxel]

Even corvette forum is better than that.. but not by much though. It's insane. Say something bad about a vendor on there and unless you have irrefutable proof, the thread will get locked.. and even if you do, it will probably get locked and moved to a different section where no one will ever notice it.

I saw one guy who had a massive build thread, had been on the forum for 10+ years say one bad thing about a vendor. He was ticked off they wouldn't take a defective part back because it was beyond their warranty period (but had never been used because his build took so long). He just said it would make them look good if they would take it back given the number of people reading his build thread. The vendor got his build thread locked and I think they even banned him for a few months. I couldn't believe it. The bad part is there's no history of stuff like that.. if you don't see it when it happens then you'll think everything is perfect with every vendor on there. I always wonder how liable the forum could be if they KNOW someone is ripping people off and continue to hide it from other members.

Oh well--back to widebands. I still need to order me one of these. I'm going to though as soon as the gauge less version comes out

[GHuggins]

Dr. Mike, can these be ordered straight from you or do "we" still have to purchase them and then send them to you for the update?

I always try to tune vehicles with widebands in each bank... Between this and reading plugs on at least the bigger builds, it's amazing what air fuel ratios can tell you if you kinda know what your seeing - such as incomplete burns from timing (had timing too retarded on one last week - good air fuel on bank 1 but bank 2 was lean due to incomplete burn) then they're great for seeing misfires not necessarily felt during wot pulls and so on... Plug reading is great for seeing rear cylinder lean out.... Been having decent luck activating individual cylinder injector controls to richen these back up...

The misfires and the fact that you can see actual cylinder dropouts with this wideband make me very interested... I'm not a huge fan of the bosch sensors if I'm being 100% honest - had lots of problems in the past with wot richer fueling and egt temperature swings killing them while trying to dial in VE tables, but I'm open to giving this a try...

[schpenxel]

Individual cylinder controls have worked for you? That is awesome. I've never messed with those

[LSxpwrdZ]

Individual cylinder controls have worked for you? That is awesome. I've never messed with those

I've not messed with the cylinder fueling but have done the cylinder timing and it for sure works. Comes in super handy for power adder cars where certain cylinders are hotter than others.

[dr.mike]

Dr. Mike, can these be ordered straight from you or do "we" still have to purchase them and then send them to you for the update?

The gauge is , now, an official part from AEM. Part# 30-0333 is a 30-0300 w/ the firmware update and a pre-wired splitter cable. So, you should be able to call AEM, or one of their distributors, to get hold of one.

AFAIK, they have not done the non-gauge "inline" WB, yet. I think they are waiting to see how popular the gauges are.
If it is going to be a while, I MIGHT offer them, with the splitter cables, until AEM has them ready.

I'm not a huge fan of the Bosch sensors if I'm being 100% honest - had lots of problems in the past with wot richer fueling and egt temperature swings killing them while trying to dial in VE tables,

That is a problem with the Bosch sensors. And, more so with the 4.9 than the older 4.2. They require VERY tight control of the sensor heater to maintain a constant temperature under changing EGTs. Several controller brands do not do a very good job of this. The AEM gauge actually uses a DC power-supply to run the heater, rather than the normal switched 12v PWM signal. That may help some. I have not heard of any coming back for this.

[5FDP]

Is it normal that my face hurts after reading this whole thread???

[jsllc]

Here is a short run on my ZL1 after tuning both the SD and MAF on the E67 with the AEM inline version. I spent 4 months and could not get close. Just a few hours and the car likes the information it was given.

[dr.mike]

Individual cylinder controls have worked for you? That is awesome. ...

Not quite the same thing. But, a few years back, using a specially set up LC-1 ( which is slower than the 30-0300 ), I was able to tune individual cylinder idle and transition on a Ferrari 365GTB/4 V12 which has individual carburetors for each cylinder. I hooked up a scope to the analog out and triggered off of the #1 sparkplug wire. The humps and valleys in the trace were pretty clear, moving, as I turned the idle mixture screws.

That was MUCH easier than the old way to do it !

P5261020-b.jpg

[dr.mike]

jsllc, that trace reminds me of a formula.

Air/fuel ratio is not just a combustion quality value. It is, literally, the mass ratios of air to fuel.

So,

MAF = fuelflow x AFR. ( in like units )

With a fast enough WB you can, actually, calculate MAF, CFM and VE, directly from fuel flow, rpm, IAT and engine displacement, in real time.

i.e. IIRC ...

MAF ( lbs/hr) = AFR x FuelFlow(lbs/hr)
CFM = MAF ( lbs/hr) x 0.02237 ( @25C . should be adjusted for IAT )

VE = 100 x (2 x MAF(lbs/hr) x 386.58 ) / ( Displacement(CI) X RPM )

Assuming you measure fuel flow correctly, this should be usable for characterizing a MAF sensor. Or building a VE map.