MAF calibrations for bigger intakes

[Lex]

I've gotten a good amount of data for the HTP intake now to see that it is fairly close. Of course use at your own risk but the MAF calibration in the OP should be a very good start for the HTP 3" users.

[Deldran]

Originally Posted by Lex I've gotten a good amount of data for the HTP intake now to see that it is fairly close. Of course use at your own risk but the MAF calibration in the OP should be a very good start for the HTP 3" users.

Weather has been crappy here this weekend hopefully I can get u some logs for the 3.5 in the next couple days

Sent from my Galaxy Nexus using Tapatalk 2

[Deldran]

@Lex;

Here are some logs. It seems i can never get the 3rd and 4th breakpoints to learn anything. its hard for me to spend much time in those areas.
The knock i am seeing in the WOT log is not normal for me, usually i might only see 1 or 2 blips for .35

Also uploaded my map for referance

[sidekick]

@Lex; Now that I'm using your MAF Cal. for the HTP 3", I'm having some issues with the car bogging down when coming to a stop. Could this be related to the MAF Cal.? I never noticed it before that.

[mrdouble99]

Wow Thanks Lex

[Lex]

Originally Posted by boost_addict @Lex; Now that I'm using your MAF Cal. for the HTP 3", I'm having some issues with the car bogging down when coming to a stop. Could this be related to the MAF Cal.? I never noticed it before that.

Could be any number of things. Use LTFTs and WOT AFRs as a guide.

BTW this cal is here to help you guys out and get you started. I am not supporting "issues" people have with the calibration.

[sidekick]

Originally Posted by Lex Could be any number of things. Use LTFTs and WOT AFRs as a guide. BTW this cal is here to help you guys out and get you started. I am not supporting "issues" people have with the calibration.

I wasn't looking for support, simply wondering if other people have had similar issues. Thanks.

[Lex]

Originally Posted by boost_addict I wasn't looking for support, simply wondering if other people have had similar issues. Thanks.

I know, I just wanted to make it clear that these are use at your own risk calibrations .

[Lex]

Added a BETA 3.5" HTP calibration to the OP. Try it out and give me some feedback.

[Deldran]

Originally Posted by Lex Added a BETA 3.5" HTP calibration to the OP. Try it out and give me some feedback.

Flashing the Beta cal today.
Its interesting because my maf that i was calibrating had the same little humps in the curve, as your beta does. Those humps where why i decided to try the JBR maf cal. Figured i had messed it all up

[Lex]

Originally Posted by Deldran Flashing the Beta cal today. Its interesting because my maf that i was calibrating had the same little humps in the curve, as your beta does. Those humps where why i decided to try the JBR maf cal. Figured i had messed it all up

Post up the results.

[Deldran]

Here are the results.
seems pretty close. I am targeting 11.8 at WOT its a little lean at first then seems to get pretty close the rest of the way through.

Still cant seem to get it to learn a trim for the 4th breakpoint. i dont think i ever get to it until i do a maf cal log.

[Lex]

Originally Posted by Deldran Here are the results. seems pretty close. I am targeting 11.8 at WOT its a little lean at first then seems to get pretty close the rest of the way through. Still cant seem to get it to learn a trim for the 4th breakpoint. i dont think i ever get to it until i do a maf cal log.

Is this based on the cal I posted or were there any changes made? Also what year is your car?

[Deldran]

Originally Posted by Lex Is this based on the cal I posted or were there any changes made? Also what year is your car?

Its an 07.
no changes made. flashed your htp 3.5 beta cal and ran it for ~80 miles

why strange results?

[Lex]

Originally Posted by Deldran Its an 07. no changes made. flashed your htp 3.5 beta cal and ran it for ~80 miles why strange results?

I would like to change the idle region and there is a bit of a bump at around 200 g/s but nothing major.

Can you change your LTFT breakpoints to the following and put some miles on it and get a MAF cal?

A:5.70, B:12, C:20, D:30, E:40 F:150g/s

[Deldran]

Originally Posted by Lex I would like to change the idle region and there is a bit of a bump at around 200 g/s but nothing major. Can you change your LTFT breakpoints to the following and put some miles on it and get a MAF cal? A:5.70, B:12, C:20, D:30, E:40 F:150g/s

Will do. By maf cal you mean log. or you want me to get it all calabrated

[Lex]

Originally Posted by Deldran Will do. By maf cal you mean log. or you want me to get it all calabrated

MAF cal log once you have 40-60 miles on the flash.

[klafaille]

@Lex;

Here's an older MAF cal I have for a JBR 3.5" that is +/- 4.5ish using 93 octane. It should be great for getting up and running before fine tuning the cal.

I don't doubt in the least that zero'ing everything to 0.9 is useful, but I don't have any CEL or bouncing idle and it idles fine at 14.7/14.8 AFR.

Dunno if this is useful at all, but I figured I'd post it up.

0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.04	0.05	0.11	0.16	0.24	0.32	0.43	0.56	0.72	0.86	1.04	1.24	1.45	1.69	1.96	2.23	2.53	2.88	3.25	3.65	4.34	5.08	6.83	6.34	6.98	7.75	8.63	9.30	10.32	11.28	12.13	13.10	14.14	15.33	16.54	17.67	20.06	21.36	23.03	24.78	26.57	28.40	28.97	30.87	32.77	34.68	36.58	38.98	41.52	44.17	46.96	50.23	53.23	56.35	59.57	62.93	66.42	70.02	72.86	75.69	77.86	83.53	88.04	92.54	100.67	106.94	113.22	114.90	118.21	121.53	124.24	133.29	140.25	143.63	147.01	151.48	158.90	165.00	171.17	175.88	183.99	190.64	195.61	202.53	211.59	216.93	226.60	232.35	242.63	250.95	258.62	267.33	276.24	285.35	294.68	304.21	313.91	323.79	333.88	344.22	354.76	365.51	376.50	387.73	399.22	410.94	422.90	435.10	447.55	460.24	473.21	486.43	499.90	513.64	527.64	541.92	556.47	571.30	586.40	601.79

[JDW1]

Did some testing, log attached. The beta cal on the 3" is close, from what I can tell maybe a tad rich at idle and a hair lean at the beginning of WOT, an adjustment or two should have it about perfect.

[Deldran]

@Lex;

Here is the results from what you asked.
Breakpoints changed to you suggestion. I did not get a log of the first break point. at 2k in second i am doing 10grams of flow.

If you need me to do something else to help let me know
Log 105 is 4th gear wot pull.

[Redline143]

I'll give the HTP 3.5" beta a shot too. I'm also inputting the breakpoints you suggested to Deldran, @Lex.

As I'm a student of the tune, do you mind explaining those breakpoints? Are they merely temporary as you're refining the 3.5 HTP sensor table more? It seems like placing them close like that near the beginning can help you gather helpful data. Why jump from 40 to 150? That seems like a really big jump with all of the other breakpoints so close...

[Voltwings]

Originally Posted by Redline143 I'll give the HTP 3.5" beta a shot too. I'm also inputting the breakpoints you suggested to Deldran, @Lex. As I'm a student of the tune, do you mind explaining those breakpoints? Are they merely temporary as you're refining the 3.5 HTP sensor table more? It seems like placing them close like that near the beginning can help you gather helpful data. Why jump from 40 to 150? That seems like a really big jump with all of the other breakpoints so close...

you have to think about spool, once the turbo gets going it starts pulling in substantially more air. Do a data log of daily driving, then get on it a bit part throttle and take a look at what your G/s do and those break points will make a lot more sense.

[Redline143]

Originally Posted by Voltwings you have to think about spool, once the turbo gets going it starts pulling in substantially more air. Do a data log of daily driving, then get on it a bit part throttle and take a look at what your G/s do and those break points will make a lot more sense.

I realize that it would also help one to dial-in the lower region of the MAF sensor table a lot better too. Wouldn't it avail more resolution in the 0 to 40 range by having so many breakpoints? My logic may be flawed, but that's what I would think.

Then, to dial in the high side of the MAF cal table, maybe using breakpoints that are far spaced down low (in terms of grams/sec) and closer together up top (also in terms of grams/sec) could help?

Are you saying, @Voltwings, that these suggested breakpoints aren't temporary? That they're for more than just getting the 3.5 BETA table dialed in? If these breakpoints work well and are meant for continual (rather than temporary) use, I'd happily do so. I'm just really used to 5.7/18/50/75/120/150 (Bucker's suggested) which seems to be a more balanced, evenly-distributed scheme.

[Voltwings]

Originally Posted by Redline143;1898446 Are you saying, [MENTION=9219 Voltwings, that these suggested breakpoints aren't temporary? That they're for more than just getting the 3.5 BETA table dialed in? If these breakpoints work well and are meant for continual (rather than temporary) use, I'd happily do so. I'm just really used to 5.7/18/50/75/120/150 (Bucker's suggested) which seems to be a more balanced, evenly-distributed scheme.

I'm using buckers breakpoints on my 4" and they work just fine. However, your maf cal is based off whatever breakpoints you are using, if you do a Maf cal and then change your breakpoints, you will more than likely need a new calibration so its a bit of a step in the wrong direction.

[Redline143]

Originally Posted by Voltwings I'm using buckers breakpoints on my 4" and they work just fine. However, your maf cal is based off whatever breakpoints you are using, if you do a Maf cal and then change your breakpoints, you will more than likely need a new calibration so its a bit of a step in the wrong direction.

Yeah, that's what I was thinking. I'll gladly use new breakpoints to gather data and help the community, in general, and Lex's MAF chart for the HTP 3.5, specifically.

I was just trying to figure out if the breakpoints that Deldran and I are using are meant solely for data gathering, and that we'd change them later for more precise AFRs, or if the breakpoints will basically be the new ones that Lex is suggesting we use from now on.

Honestly, I find a lot a variation on suggested breakpoints. I'm not quite sure which work best and why. Also, I realize that "best" is often highly relative and goal-specific. I'm running E40, so that factor may alter "most accurate AFR breakpoints" (probably a better term than "best") even more. I've already noticed positive LTFT values across the board (in the +3 to +8 range, except a -3 or so at idle) in the 40 or so miles I've driven. I primarily attribute this to my ethanol blend.

Care to chime in, @Lex?

[Lex]

I will chime in to the breakpoints. The MAF curve is exponential. The higher you go in the curve the fewer points for resolution you have.

Further, take a log when normally driving. You almost never find yourself at 70 or even 120 g/s. Since the car spends very little time in that area of the curve it will take a LONG time for the ECU to learn the LTFTs. LTFTs are important to learn quickly because this is the ECU's way of calibrating your MAF. So if you have a point between 70 and 125 the car will almost never be in that area and the ECU won't apply the calibrations it learns before this to that area meaning it has to wait for STFTs to respond.

So there is logic behind the placement of my LTFT breakpoints and it is related to the way the vehicle is driven, increasing the speed at which LTFTs are learned, and finally taking into account the exponential like rise in mass airflow with respect to sensor voltage. Even distribution of the separation points in this case is not the correct way to approach this.

[Deldran]

Originally Posted by Lex I will chime in to the breakpoints. The MAF curve is exponential. The higher you go in the curve the fewer points for resolution you have. Further, take a log when normally driving. You almost never find yourself at 70 or even 120 g/s. Since the car spends very little time in that area of the curve it will take a LONG time for the ECU to learn the LTFTs. LTFTs are important to learn quickly because this is the ECU's way of calibrating your MAF. So if you have a point between 70 and 125 the car will almost never be in that area and the ECU won't apply the calibrations it learns before this to that area meaning it has to wait for STFTs to respond. So there is logic behind the placement of my LTFT breakpoints and it is related to the way the vehicle is driven, increasing the speed at which LTFTs are learned, and finally taking into account the exponential like rise in mass airflow with respect to sensor voltage. Even distribution of the separation points in this case is not the correct way to approach this.

Most of the time if you are in the 70+ range won't you also be in open loop where ltft doesn't matter?

At least that seems to be my experiance

Sent from my Nexus 4 using Tapatalk 2

[Redline143]

Originally Posted by Lex I will chime in to the breakpoints. The MAF curve is exponential. The higher you go in the curve the fewer points for resolution you have. Further, take a log when normally driving. You almost never find yourself at 70 or even 120 g/s. Since the car spends very little time in that area of the curve it will take a LONG time for the ECU to learn the LTFTs. LTFTs are important to learn quickly because this is the ECU's way of calibrating your MAF. So if you have a point between 70 and 125 the car will almost never be in that area and the ECU won't apply the calibrations it learns before this to that area meaning it has to wait for STFTs to respond. So there is logic behind the placement of my LTFT breakpoints and it is related to the way the vehicle is driven, increasing the speed at which LTFTs are learned, and finally taking into account the exponential like rise in mass airflow with respect to sensor voltage. Even distribution of the separation points in this case is not the correct way to approach this.

As you explain this, it makes perfect sense. Looking at the plot of the MAF curve itself shows quite clearly that an exponential equation is used. Therefore, having breakpoints that are very close together at first and get progressively wider-spaced makes a lot of sense. I didn't know that having the ECU learn trims very quickly has benefits. I'll take your word for it, as I know you're very well-informed about our ECUs. That provides even more support to have lots of closely-spaced breakpoints down low, then moving to more widely-spaced up top.

Thanks, @Lex. So, just to be clear, you recommend these breakpoints for long-term use? Based on what you said, that would make sense. It's not about getting your HTP 3.5 dialed in at all. They're great points to use always, right?

[Lex]

Originally Posted by Redline143 As you explain this, it makes perfect sense. Looking at the plot of the MAF curve itself shows quite clearly that an exponential equation is used. Therefore, having breakpoints that are very close together at first and get progressively wider-spaced makes a lot of sense. I didn't know that having the ECU learn trims very quickly has benefits. I'll take your word for it, as I know you're very well-informed about our ECUs. That provides even more support to have lots of closely-spaced breakpoints down low, then moving to more widely-spaced up top. Thanks, @Lex. So, just to be clear, you recommend these breakpoints for long-term use? Based on what you said, that would make sense. It's not about getting your HTP 3.5 dialed in at all. They're great points to use always, right?

Correct, these breakpoints is what I would use all the time unless there are specific reasons not to.

[Redline143]

Okay, so here are my initial results and logs. I've included 4 MAF cal logs and 1 driving around log. These logs were taken with ~60 miles since flashing:

0.88-1.14 volts: -2.34 LTFT (will multiply voltage range by 0.9766 to adjust)
1.16-1.51 volts: +3.91 LTFT (will multiply voltage range by 1.0391 to adjust)
1.54-1.73 volts: +7.03 LTFT (will multiply voltage range by 1.0703 to adjust)
1.74-1.94 volts: +1.56 LTFT (will multiply voltage range by 1.0156 to adjust)
1.96-2.15 volts: +7.81 LTFT (will multiply voltage range by 1.0781 to adjust)
2.16-3.15 volts: +8.59 LTFT (will multiply voltage range by 1.0859 to adjust)

Hope these data help, @Lex



I'm calibrating, reflashing, and I'll repost the new results after another ~60 miles or so.

[Lex]

Originally Posted by Redline143 Okay, so here are my initial results and logs. I've included 4 MAF cal logs and 1 driving around log. These logs were taken with ~60 miles since flashing: 0.88–1.14 volts: -2.34 LTFT (will multiply voltage range by 0.9766 to adjust) 1.16–1.51 volts: +3.91 LTFT (will multiply voltage range by 1.0391 to adjust) 1.54–1.73 volts: +7.03 LTFT (will multiply voltage range by 1.0703 to adjust) 1.74–1.94 volts: +1.56 LTFT (will multiply voltage range by 1.0156 to adjust) 1.96–2.15 volts: +7.81 LTFT (will multiply voltage range by 1.0781 to adjust) 2.16–3.15 volts: +8.59 LTFT (will multiply voltage range by 1.0859 to adjust) Hope these data help, @Lex I'm calibrating, reflashing, and I'll repost the new results after another ~60 miles or so.

Thanks for the data. How are the WOT AFRs?

[Redline143]

Originally Posted by Lex Thanks for the data. How are the WOT AFRs?

@Lex,
I haven't pulled any WOT logs yet. I was planning on doing so after the second calibration.

Would you like some pre-second calibration WOT logs? So far, my LTFTs have settled down pretty well. I'm now in the -3.7 to +5.5 range across the voltage/airflow spectrum. Several of the breakpoint ranges are actually within +/- 0.8 after my first revision, so they seem pretty much perfect.

Update: I just did the second recalibration:

1.06–1.11 volts: -3.12 LTFT (will multiply voltage range by 0.9688 to adjust)
1.12–1.42 volts: +3.91 LTFT (will multiply voltage range by 1.0391 to adjust)
1.68–2.10 volts: +0.78 LTFT (will multiply voltage range by 1.0078 to adjust)
2.12–3.16 volts: -0.78 LTFT (will multiply voltage range by 0.9922 to adjust)

The gaps in voltages represent regions that had an LTFT of 0.

These LTFTs were ~80 miles after flashing. I'll reflash the new map and do WOT logs for you. Do I need to wait a certain amount of time for the LTFTs to settle in for the purposes of gathering useful data on the WOT logs? I wasn't sure if the ECU needed some time to adjust to extrapolate the trims for WOT runs more accurately. If I don't hear back from you soon, I'll just wait ~50 miles before WOT logging.

[Lex]

Originally Posted by Redline143 @Lex, I haven't pulled any WOT logs yet. I was planning on doing so after the second calibration. Would you like some pre-second calibration WOT logs? So far, my LTFTs have settled down pretty well. I'm now in the -3.7 to +5.5 range across the voltage/airflow spectrum. Several of the breakpoint ranges are actually within +/- 0.8 after my first revision, so they seem pretty much perfect. Update: I just did the second recalibration: 1.06–1.11 volts: -3.12 LTFT (will multiply voltage range by 0.9688 to adjust) 1.12–1.42 volts: +3.91 LTFT (will multiply voltage range by 1.0391 to adjust) 1.68–2.10 volts: +0.78 LTFT (will multiply voltage range by 1.0078 to adjust) 2.12–3.16 volts: -0.78 LTFT (will multiply voltage range by 0.9922 to adjust) The gaps in voltages represent regions that had an LTFT of 0. These LTFTs were ~80 miles after flashing. I'll reflash the new map and do WOT logs for you. Do I need to wait a certain amount of time for the LTFTs to settle in for the purposes of gathering useful data on the WOT logs? I wasn't sure if the ECU needed some time to adjust to extrapolate the trims for WOT runs more accurately. If I don't hear back from you soon, I'll just wait ~50 miles before WOT logging.

LTFTs are not going to affect WOT so no you don't need to wait to take WOT logs.

So are you on the 2nd cal right now or the 3rd? You supplied 2 sets of adjustments. Did you apply both or did you let the trims settle more and then just applies the 2nd set quoted here to the MAF calibration in the OP?

[Redline143]

Originally Posted by Lex LTFTs are not going to affect WOT so no you don't need to wait to take WOT logs. So are you on the 2nd cal right now or the 3rd? You supplied 2 sets of adjustments. Did you apply both or did you let the trims settle more and then just applies the 2nd set quoted here to the MAF calibration in the OP?

I wasn't sure about LTFTs affecting WOT AFR--thanks for clarifying, @Lex

I applied each set of adjustments when I posted the data. I didn't wait for the trims to settle any more before doing so.

So, first I applied your 3.5 HTP MAF table and flashed the map. I ran about ~60 miles and adjusted the MAF sensor table with the values I first posted. Then, I reflashed.

After reflashing, I ran about ~80 miles and did another MAF sensor table calibration with the values I second posted. Then, I reflashed.

So, I'm on the 3rd map. The first was what you gave me. The second was after the first ~60 miles. The third (which I'm on right now) was after ~80 miles. The two sets of logs and data I posted were from between the 1st and 2nd flash, and the 2nd and 3rd flash.

So far, I have 0 miles on the newest (the 3rd) flash. I commuted with my wife to work today. Since today's my birthday, so I'm not sure if I'll be able to pull WOTs tonight, but I'll try to do so soon.

Let me know if this response clarified things for you, or if you have further questions.

[Lex]

Originally Posted by Redline143 I wasn't sure about LTFTs affecting WOT AFR--thanks for clarifying, @Lex I applied each set of adjustments when I posted the data. I didn't wait for the trims to settle any more before doing so. So, first I applied your 3.5 HTP MAF table and flashed the map. I ran about ~60 miles and adjusted the MAF sensor table with the values I first posted. Then, I reflashed. After reflashing, I ran about ~80 miles and did another MAF sensor table calibration with the values I second posted. Then, I reflashed. So, I'm on the 3rd map. The first was what you gave me. The second was after the first ~60 miles. The third (which I'm on right now) was after ~80 miles. The two sets of logs and data I posted were from between the 1st and 2nd flash, and the 2nd and 3rd flash. So far, I have 0 miles on the newest (the 3rd) flash. I commuted with my wife to work today. Since today's my birthday, so I'm not sure if I'll be able to pull WOTs tonight, but I'll try to do so soon. Let me know if this response clarified things for you, or if you have further questions.

Seems like you're on the right track! Happy Birthday and post up the results from the 3rd calibration. Also FIY there are WOT trims that can go +/- 12% on gen2 cars. We can't log these trims. So we won't know how far the MAF is off at WOT in the gen2 cars unless it's more than +/- 12%

[Redline143]

Originally Posted by Lex Seems like you're on the right track! Happy Birthday and post up the results from the 3rd calibration. Also FIY there are WOT trims that can go +/- 12% on gen2 cars. We can't log these trims. So we won't know how far the MAF is off at WOT in the gen2 cars unless it's more than +/- 12%

Thanks!

Wow, +/- 12% is definitely significant--I had no idea!

FWIW, I started with the JBR 3.5 curve you originally had posted on this thread on the previous calibration I was running. After getting things dialed-in, I was virtually always within 11.8 to 12.2 when targeting 12.0 AFR on my E40 mix. That means I was withing +/- 1.67%. I did virtually no WOT calibration too--there was no need.

If I can be within that range with this new calibration, I'll be happy. I notice the max JBR voltage shows over 600 grams/sec. This new calibration I'm using maxes out at about ~586. In other words, a 2.3% difference in flow at max voltage. The results should be interesting.

[Lex]

Originally Posted by Redline143 Thanks! Wow, +/- 12% is definitely significant--I had no idea! FWIW, I started with the JBR 3.5 curve you originally had posted on this thread on the previous calibration I was running. After getting things dialed-in, I was virtually always within 11.8 to 12.2 when targeting 12.0 AFR on my E40 mix. That means I was withing +/- 1.67%. I did virtually no WOT calibration too--there was no need. If I can be within that range with this new calibration, I'll be happy. I notice the max JBR voltage shows over 600 grams/sec. This new calibration I'm using maxes out at about ~586. In other words, a 2.3% difference in flow at max voltage. The results should be interesting.

At WOT your ECU was adjusting your AFRs so you may have been further off. The JBR calibration is pretty good though and yes, his 3.5" has more flow headroom.

[Redline143]

Originally Posted by Lex At WOT your ECU was adjusting your AFRs so you may have been further off. The JBR calibration is pretty good though and yes, his 3.5" has more flow headroom.

Makes sense... I kinda wish the HTP flowed more than the JBR, but it would only be bragging rights. There's no way I'll be maxing out my setup. I'm thinking of a BNR S3 one day, and I know that won't be a flow issue.

Gosh, even with a GTX3076 or larger, it probably wouldn't be an issue. I don't think I've ever seen a single log with 500+ grams/second, let alone almost 600, LOL!

[Redline143]

Alright, @Lex, here are the results from the 3rd flash. So, to recap: I did your initial Beta calibration table, drove ~60 miles, pulled logs, then recalibrated and flashed again. After running ~80 miles, I pulled more logs and then flashed again. I'm now on this 3rd calibration. I have driven ~60 miles before pulling these most recent (attached) logs. I have 2 WOT runs, 1 MAF cal run, and then a final run where I was sitting at a stop light, casually getting on an onramp, then coming to cruising speed on the highway.

The MAF cal shows I'm within +/- 1.56 for all ranges but one, which shows 3.12. One final calibration should lock my closed loop in nicely.

Regarding the WOT runs, you tell me. I'm targeting 12.0AFR. These logs look good to me; what say you? Since you're looking at them, can you offer me any insight or advice at all on how they look? My initial boost spike is brief and ~1.5 higher than my 21.0 target. I wonder if there's anyway to eliminate the initial WOT 10.x AFR I seem to always see.

Anyways, I hope these data help

[Lex]

I would not try and chase your tail with a 3.x LTFT. That is more than within spec - leave it as you will see more fluctuations from changes in weather.

As for the WOT regions, did you modify the WOT region at all from the original MAF cal you started from?