JB4 on G20 330i

[VipinLJ]

Looks fine

Throttle never fully opens up but then again it never did when we first started doing this map 6 either

Timing is all good

Seems fine to me

Yes it doesn't. Thank God it's nothing I can feel :D

And yes. As long as it's fine, I'm more than happy! Thank you very much once again!!

[Turboh]

I managed to get a log of sorts today on the highway. Freezing cold here plus roads were a bit slippery because of the rains. I just want to make sure everything is ok. Car performs great as far as I can tell.

Couldn't start lower than roughly 2600 because I saw lights approaching from far behind me and didn't want to be "that guy" on the highway.

Fuel ~ E25

Hi,

Just a quick look and comparing to my runs on 93 octane and no EWG, your acceleration is quite good, but the throttle is really erratic along with the trims, and FF and WGDC. I run V17, not V19. Your timing is excellent so I would expect better performance. My instinct says drop the gain, go back to additive map 6 and tweak the ff / wgdb settings. You should go smoother and faster. IMHO

As an aside, I just had my first tranny code. I deleted it via JB4 but wonder what you found out when you had it.

Thanks,

Alex

[VipinLJ]

Hi,

Just a quick look and comparing to my runs on 93 octane and no EWG, your acceleration is quite good, but the throttle is really erratic along with the trims, and FF and WGDC. I run V17, not V19. Your timing is excellent so I would expect better performance. My instinct says drop the gain, go back to additive map 6 and tweak the ff / wgdb settings. You should go smoother and faster. IMHO

As an aside, I just had my first tranny code. I deleted it via JB4 but wonder what you found out when you had it.

Thanks,

Alex

Hey Alex!

Yes. My throttle definitely is very erratic. But no matter what we (basically KnifeEdge87) did, we couldn't smoothen it out. Funny thing is, before I installed the EWG connector, I think it was smooth (though it never went to 100% IIRC). But that was also a different map 6.

So you're saying I should try setting it at 6 all through and then fiddle with the FF/wgdb (I honestly have no idea what those are) to try fix it? I would have if I knew how to.

The only thing I am looking at is the way the car drives and engine feels (seat of the pants). It pulls great and honestly feels extremely smooth too. I always thought piggybacks made a car drive slightly rough compared to a flash tune but this is not the case in my car.

And the code I got was 11A605. I'm not sure that was a tranny code (?) but I could be wrong. I read somewhere that it was related to fuel starvation. I think it was the supramkv forum. I'll have to Google it again. The reason I kept thinking it was that was because it happened twice when fuel was extremely low (1 gallon or less) and once when I pulled out of the gas station right after filling up. Nowadays, I always fill my tank up the moment the low fuel indicator comes on or when I notice my car is at around 60 miles to empty. I've never had the code pop up after those times. I also remember you saying it was the high load (when you went through my logs) which could also be the reason (I'm a total noob).
When did you get the code? What were the conditions?
When I got the codes, my car jerked for a second before the drivetrain malfunction popped up. It drove smooth after that even though the malfunction was present on the idrive. Also, right before the malfunction popped up, the car felt like it lost some power (when it happened twice after the first, I could tell my car was going to throw the code a second or so before it actually did and before the car jerked). Also, it happened at WOT.

Regards,
Vipin

[KnifeEdge87]

I’m not even sure what the FF and wgdc(Pwm) fields do on our cars with electronic waste gate actuation.

On the older pneumatic wastegate engines control of the actuation was based on vacuum lines and solenoids. ( you can’t tell the wastegate to open 70%, you can only say open/close the vacuum solenoid X times per sec to try and achieve this )

On electronic wastegates I can only assume that it’s a lot easier since you just tell the servomotor (wastegate to X position)

BMS has not really provided much info on what user adjustable fields we have or how we can use them for electronic wastegate engines. Or if they have, I haven’t seen it. Most of the info I see floating around is still from the pwg engine days and there are still references to things which obviously don’t/can’t do anything, like the fuel bias and fuel open loop fields when the b series jb4 does not have any connections/control over the fuel system.

I think what would be helpful in a later update for the b series EWG equipped software is user defined “psi underreport” variable. I might be talking out of my ass but there seems to be enough cases of throttle closure which is related to mild overboosting that isn’t causing timing drops (like vipin’s case) that this might be worth looking at. Hell... if we are thinking of what we would like to add maybe a “throttle wire” so we have direct control of throttle opening which seems to be how bmw is artificially kneecapping the retuned b48 variants. Of course this presents a certain level of danger given the throttle is an inherent safety device though it’s no more dangerous than a flash tune which does the “same” thing. What it would need though is more r&d on BMS’s part to get it in a “ready for retail” state. BMS will need to find what signals lead to legitimate throttle closures and let those signals through whereas ignore the signals which cause the inexplicable unwanted throttle closures.

[KnifeEdge87]

Please correct me if I’m wrong but a lot of the for/pidpwm/wgdc stuff and “learning” functionality was ONLY applicable to pwg since each car may need a different vacuum/solenoid activation frequency to achieve a given wastegate position or boost control dynamic.

Again, for electronic wastegates I can only assume that this problem doesn’t exist as the position control should be a lot more direct (to be fair this Is still only HALF the problem since wastegate position doesn’t directly correlate one to one with boost)

[Turboh]

Please correct me if I’m wrong but a lot of the for/pidpwm/wgdc stuff and “learning” functionality was ONLY applicable to pwg since each car may need a different vacuum/solenoid activation frequency to achieve a given wastegate position or boost control dynamic.

Again, for electronic wastegates I can only assume that this problem doesn’t exist as the position control should be a lot more direct (to be fair this Is still only HALF the problem since wastegate position doesn’t directly correlate one to one with boost)

Hi Knife,

Check this posting, if you have not done so. I found it quite good and after reading it 20 times and trying changes on the settings, it does seem to help.

I have not installed the ewg wire yet.

JB4 Duty Bias FF Tuning Info - N54Tech.com - International Turbo Racing Discussion

[KnifeEdge87]

If you don't have an EWG by definition the settings you're talking about can't help. They all relate to wastegate control which you don't have if all you're hooked up to are the pre throttle pressure sensor and manifold pressure sensor.

I refuse to trust my butt dyno for anything other than "fun factor" since the brain plays so many tricks on you.

[KnifeEdge87]

Even with numbers (logs showing before and after) your brain can play tricks on you

Things may have improved but the cause certainly can't be due to you changing fields that you KNOW can't do anything

Like for me I ran into severe throttling issues again when in map 0 because of the bmw detuning gremlins the past few weeks. But yesterday I ran a 3rd gear pull again and lo and behold no throttling issues. It could be due to any number of reasons. I had filled up at another gas station recently, it could be air temps, could just be random luck, could be the dme somehow adjusting itself to good knows what, etc.

To try and associate a change in result with a change in input requires keeping as much as possible the other variables constant which in this day and age is extremely difficult even when on a dyno and outright impossible on the road.

Finding the true source of something is hard enough without us trying to find solutions where they can't possibly be hiding.

I apologize if I am being a bit harsh but I really have to stand quite firm on these points. In general across all things in life now, there is way too much misinformation out there that I really don't want to contribute to it.

I'm not claiming to be a tuning expert but I'd like to think I'm knowledgeable enough that if a claim doesn't smell right to me that at the very least, it requires further investigation.

Likewise if I ever say anything that's unsubstantiated or not well thought out or whatever, absolutely do NOT just take my word on it. At the end of the day the stuff we are talking about is not that complicated, we aren't taking about hardware changes and whether porting a head is good or bad because it improves or hurts the swirl of air fuel mixture in the combustion chamber (this is not applicable to our engines, just something off the top of my head). Hell at the moment we aren't even taking about tuning in the strictest sense of the word, all we are doing is boost control. If I can't manage to convince someone of what I'm saying, then that is absolutely MY problem unless who I'm talking to has down syndrome.

[KnifeEdge87]

Btw

Shall we start a whatsapp group or something?

[Turboh]

Hey Alex!

Yes. My throttle definitely is very erratic. But no matter what we (basically KnifeEdge87) did, we couldn't smoothen it out. Funny thing is, before I installed the EWG connector, I think it was smooth (though it never went to 100% IIRC). But that was also a different map 6.

So you're saying I should try setting it at 6 all through and then fiddle with the FF/wgdb (I honestly have no idea what those are) to try fix it? I would have if I knew how to.

The only thing I am looking at is the way the car drives and engine feels (seat of the pants). It pulls great and honestly feels extremely smooth too. I always thought piggybacks made a car drive slightly rough compared to a flash tune but this is not the case in my car.

And the code I got was 11A605. I'm not sure that was a tranny code (?) but I could be wrong. I read somewhere that it was related to fuel starvation. I think it was the supramkv forum. I'll have to Google it again. The reason I kept thinking it was that was because it happened twice when fuel was extremely low (1 gallon or less) and once when I pulled out of the gas station right after filling up. Nowadays, I always fill my tank up the moment the low fuel indicator comes on or when I notice my car is at around 60 miles to empty. I've never had the code pop up after those times. I also remember you saying it was the high load (when you went through my logs) which could also be the reason (I'm a total noob).
When did you get the code? What were the conditions?
When I got the codes, my car jerked for a second before the drivetrain malfunction popped up. It drove smooth after that even though the malfunction was present on the idrive. Also, right before the malfunction popped up, the car felt like it lost some power (when it happened twice after the first, I could tell my car was going to throw the code a second or so before it actually did and before the car jerked). Also, it happened at WOT.

Regards,
Vipin

Hi Vilpin,

Finally managed the convert file forms to something the system would take. Review and compare. Let me know what you think.

Alex

[Turboh]

If you don't have an EWG by definition the settings you're talking about can't help. They all relate to wastegate control which you don't have if all you're hooked up to are the pre throttle pressure sensor and manifold pressure sensor.

I refuse to trust my butt dyno for anything other than "fun factor" since the brain plays so many tricks on you.

Hi Knife,

I agree on the butt dyno. I open the csv file in excel, and select the time and rpm columns, graph them using the scatterplot, select the plot and add a trendline which is linear. I then select the equation for that line. The slope of the line(the number before the x) is acceleration. It is the ratio of rpm change /time change. Simpler is to calculate your change in rpm over the entire change in time, right off the jb4 data. Track those ratios for your WOTs and you get a pretty good number for evaluating how your car performs.

My butt accelerometer has faked me out plenty of times.

Alex

[KnifeEdge87]

Hi Knife,

I agree on the butt dyno. I open the csv file in excel, and select the time and rpm columns, graph them using the scatterplot, select the plot and add a trendline which is linear. I then select the equation for that line. The slope of the line(the number before the x) is acceleration. It is the ratio of rpm change /time change. Simpler is to calculate your change in rpm over the entire change in time, right off the jb4 data. Track those ratios for your WOTs and you get a pretty good number for evaluating how your car performs.

My butt accelerometer has faked me out plenty of times.

Alex

Yea that's fine but I mean literally even seeing better numbers here just means you did better on that particular run, not that whatever you changed is the cause of that (especially if it is a change in a parameter that isn't "connected" to anything)

Vipin's car isn't getting boost to target and while your msp shows far better throttling condition. The question we should be asking ourselves is why is Vipin's car setting throttling issues in the first place.

The "downside" of using additive is you're completely beholden to whatever the dme commands. If at the same rpm sometimes the dme commands 12psi but sometimes commands 15psi there's nothing you can do to get consistent 20psi with additive.

There really isn't a solution that I can think of given the tools we have available to us. We know vipin has access to good enough gas to hit these boost levels safely as we can see from his timing but for whatever reason the dme is not opening up the throttle (which I am guessing is because the jb4 reported boost is close enough to the dme target that the stock dme is doing some throttling)

The jb4 can't underreport TOO much but it can't underreport too little. Unfortunately we have NO way to control this.

[KnifeEdge87]

Guys I have to go sleep

Hit you up in the morning (evening for you)

[Turboh]

Yea that's fine but I mean literally even seeing better numbers here just means you did better on that particular run, not that whatever you changed is the cause of that (especially if it is a change in a parameter that isn't "connected" to anything)

Vipin's car isn't getting boost to target and while your msp shows far better throttling condition. The question we should be asking ourselves is why is Vipin's car setting throttling issues in the first place.

The "downside" of using additive is you're completely beholden to whatever the dme commands. If at the same rpm sometimes the dme commands 12psi but sometimes commands 15psi there's nothing you can do to get consistent 20psi with additive.

There really isn't a solution that I can think of given the tools we have available to us. We know vipin has access to good enough gas to hit these boost levels safely as we can see from his timing but for whatever reason the dme is not opening up the throttle (which I am guessing is because the jb4 reported boost is close enough to the dme target that the stock dme is doing some throttling)

The jb4 can't underreport TOO much but it can't underreport too little. Unfortunately we have NO way to control this.

Yup, you are right on. I look at the JB4 as just a black box with a couple of wires. I have very little control over what it will do. Even the JB4 maps and descriptions and firmware are at best confusing and incomplete. All I can do is change maps and some settings and quickly see which is best for my likings. I have found that high gains can lead to rough acceleration and throttle valve fluctuations. That does make some sense. Switching to map6 additive has always been the best setup for me on the B46 and B58. Why...I am not sure.....I blame the black box.

Sleep well.

[VipinLJ]

I love how two knowledgeable guys banter back and forth. Lots of new info for me to assimilate. And I'm nowhere close unfortunately.

Regarding the throttle issue. Yes. My car is the only car I've seen so far with that issue. I even have it in map 0 now. I believe I had it in map 0 before I installed the EWG too. I did do a map 3 log a while back with the EWG and no throttle issues. But the car didn't feel fast and dragy proved that too. Back to back runs with the current map 6 showed it was much faster with map 6. I believe it might be my car alone having this issue since I'm always jinxed when it comes to automobiles/electronics etc. I seem to have the slowest stock 330i too (14.3s quarter mile times and 6s 0-60 mph times)! Probably my car was somewhat detuned from the factory?

And Alex. Yes. I'll compare your logs to mine. I've done that with some of your old logs too a while back. :D

[KnifeEdge87]

Vipin's P58_M6_R1_210115_log3rd4thEWG

There's a lot going on here but to me it looks like there's a pretty clear relationship between DME thinking there's an overboost condition (ECU_PSI/DME_BT) and throttle opening.

In the same log we also see that boost1 (the real boost) is undershooting target more and more while the wastegate remains nearly fully closed.

Now I'm getting a out of my element here but if I had to guess then I think this basically represents hitting our turbo's max flow capabilities (choke).

I've also gone and looked through your old logs

For some reason when on absolute map, the JB4 tends to report boost much closer to DMEBT than when on additive (as Alex noticed as well) which leads to the throttle staying closed for much longer. This just seems to be a JB4 thing which hopefully they can fix in later updates.

We CAN go back to additive which will resolve the throttle issue BUT we lose the stability in our absolute pressures.

Again, I don't know which way is "better". Personally I think absolute is the way to go and if BMS can change the way it reports boost to the DME when EWG is installed that would be the "best" solution

[VipinLJ]

Vipin's P58_M6_R1_210115_log3rd4thEWG

There's a lot going on here but to me it looks like there's a pretty clear relationship between DME thinking there's an overboost condition (ECU_PSI/DME_BT) and throttle opening.

In the same log we also see that boost1 (the real boost) is undershooting target more and more while the wastegate remains nearly fully closed.

Now I'm getting a out of my element here but if I had to guess then I think this basically represents hitting our turbo's max flow capabilities (choke).

I've also gone and looked through your old logs

For some reason when on absolute map, the JB4 tends to report boost much closer to DMEBT than when on additive (as Alex noticed as well) which leads to the throttle staying closed for much longer. This just seems to be a JB4 thing which hopefully they can fix in later updates.

We CAN go back to additive which will resolve the throttle issue BUT we lose the stability in our absolute pressures.

Again, I don't know which way is "better". Personally I think absolute is the way to go and if BMS can change the way it reports boost to the DME when EWG is installed that would be the "best" solution

I wouldn't be surprised if we've hit my car's turbo's ceiling with just the JB4. So if were to push my car further, what mod would you suggest next? A ca.tted D P?

Btw, if you do want to start a WhatsApp group, let me know. I'll PM you my number.

[KnifeEdge87]

please PM me
ill set up

[VipinLJ]

@KnifeEdge87

Posting some logs below with our latest numbers. Only got two logs since it was freezing cold and lots of traffic on the highway. Had to wait for it to clear completely which happened only twice.

Throttle still looks the same.

[VipinLJ]

@KnifeEdge87

Posting some logs below with our latest numbers. Only got two logs since it was freezing cold and lots of traffic on the highway. Had to wait for it to clear completely which happened only twice.

Throttle still looks the same.

Other logs

[Turboh]

Other logs

Hi Vipin,

I think your last two runs are much improved and much faster.
I changed the CVS files to excel along with graphs and summary. Both runs are smoother, with good timing and less throttle action. Trims are getting close to max at top rpm but seem OK. AFRs are fine. Both runs are in the mid to low 60s (rpm/time).
My best runs have been in the 65 range. I did notice that the throttle closed sharply, especially on one run, when the IAT increased sharply. I suspect the louvers in the grill were activated which would definitely cause a valve change. Look at the graph, they coincide. Still thinking the gain should be lowered a bit more to smoothen the engine out...I would try a gain of 12. WGC and FF are following nicely too. Could try raising the FF setting to 45, to bring both closer together. I am not sure if map 6 does auto tune. I seems it does not.

I am working on gain and ff settings too. Keep at it and let me know.

Alex

[VipinLJ]

Hi Vipin,

I think your last two runs are much improved and much faster.
I changed the CVS files to excel along with graphs and summary. Both runs are smoother, with good timing and less throttle action. Trims are getting close to max at top rpm but seem OK. AFRs are fine. Both runs are in the mid to low 60s (rpm/time).
My best runs have been in the 65 range. I did notice that the throttle closed sharply, especially on one run, when the IAT increased sharply. I suspect the louvers in the grill were activated which would definitely cause a valve change. Look at the graph, they coincide. Still thinking the gain should be lowered a bit more to smoothen the engine out...I would try a gain of 12. WGC and FF are following nicely too. Could try raising the FF setting to 45, to bring both closer together. I am not sure if map 6 does auto tune. I seems it does not.

I am working on gain and ff settings too. Keep at it and let me know.

Alex

Yes sir! I noticed that the throttle looked really nice compared to before. But the car kinda felt jerky at times. Not sure why that was. Also, when I did launch control, it seemed to kinda lose power (butt dyno; dragy showed that it didn't since 0-60 was in 4.9s or so). Well. Not exactly lose power. I'm not sure how to explain it. With the numbers KnifeEdge87 provided earlier, that did not happen. I'm trying with numbers from both of you to try and compare but the weather here isn't helping me one bit!

Also yes. I noticed trims were high (it was higher before). I still don't know what that means. Most of the others I kinda can make sense. But not sure what a high trim means. I read a few different threads (not JB4 threads or regarding BMWs) about trims and some seemed to say it was ok as long as it didn't drop much. Others said it was bad to be high all the time. So it was like reading contradictory ideas.

But yes. I'm always open to testing new numbers and settings :D

Regards,
Vipin

[VipinLJ]

Logs of map 3 and 4 below

[Turboh]

Yes sir! I noticed that the throttle looked really nice compared to before. But the car kinda felt jerky at times. Not sure why that was. Also, when I did launch control, it seemed to kinda lose power (butt dyno; dragy showed that it didn't since 0-60 was in 4.9s or so). Well. Not exactly lose power. I'm not sure how to explain it. With the numbers KnifeEdge87 provided earlier, that did not happen. I'm trying with numbers from both of you to try and compare but the weather here isn't helping me one bit!

Also yes. I noticed trims were high (it was higher before). I still don't know what that means. Most of the others I kinda can make sense. But not sure what a high trim means. I read a few different threads (not JB4 threads or regarding BMWs) about trims and some seemed to say it was ok as long as it didn't drop much. Others said it was bad to be high all the time. So it was like reading contradictory ideas.

But yes. I'm always open to testing new numbers and settings :D

Regards,
Vipin

Hi Vilpin,

I think trim is the range of adjustment available to the fuel pump. The closer to 50 means the pump is running close to not being able to supply enough fuel to meet air to fuel ratios. To me it means that you and I are getting close to fuel limits.

Gain sets up how fast the boost will rise. A fast rise seems fine for quick starts but may really test other parts of the engine controls to get a good smooth response. Smooth is fast.

Also, I am still not sure if the JB4 auto adjustments are operative on map 6. I have not seen ff settings change over time, so I suspect not. Regardless it is wise to get several runs in before logging a WOT.

I agree that the acceleration is not as smooth as you or I would like. Mine feels the same. Still working on it. I am heading toward less gain and bring the ff and wgdc curves closer together, while still have a good acceleration.

[VipinLJ]

Hi Vilpin,

I think trim is the range of adjustment available to the fuel pump. The closer to 50 means the pump is running close to not being able to supply enough fuel to meet air to fuel ratios. To me it means that you and I are getting close to fuel limits.

Gain sets up how fast the boost will rise. A fast rise seems fine for quick starts but may really test other parts of the engine controls to get a good smooth response. Smooth is fast.

Also, I am still not sure if the JB4 auto adjustments are operative on map 6. I have not seen ff settings change over time, so I suspect not. Regardless it is wise to get several runs in before logging a WOT.

I agree that the acceleration is not as smooth as you or I would like. Mine feels the same. Still working on it. I am heading toward less gain and bring the ff and wgdc curves closer together, while still have a good acceleration.

Ah yes. That does make sense. I did read a thread where someone said exactly what you said (regarding fuel supply by the pump).

And I thought it was only my car that had that issue that you felt. Since I believe my car is a one off (in being a slow one with who knows what other problems).

Let me know what you find when you tweak your settings. If I knew what to tweak, I could've helped :D

Vipin

[VipinLJ]

Mirror map 3 logs below. Along with logs with boost reduced by 0.5psi.

[Terry @ BMS]

You could lower duty bias at 5000rpm and below to try to avoid that over boost you get at the start of your run. Maybe subtract 5 per 500rpm from 5000 down.

In the future set app to combine runs in to one file, much easier to read that way later.

[VipinLJ]

You could lower duty bias at 5000rpm and below to try to avoid that over boost you get at the start of your run. Maybe subtract 5 per 500rpm from 5000 down.

In the future set app to combine runs in to one file, much easier to read that way later.

Yes sir. I'll do that and get some new logs and post here for review

[VipinLJ]

Logs with updated duty bias values

[Turboh]

Logs with updated duty bias values

Hi,

I looked quickly at your past 8 runs.

Your best acceleration run was the KE psi3, but it was very rough. You are running this in the absolute mode. The gain is very high and the throttle is almost immediately involved in controlling the boost. FF and WGDC are out of whack. Still, your acceleration was very good.

For me, the turbohval3 was the best overall. It is the smoothest, steady valve action, and WGDC and FF curves nicely lined up.

Cops will grab you on that 4th gear run...

enjoy!

[VipinLJ]

Hi,

I looked quickly at your past 8 runs.

Your best acceleration run was the KE psi3, but it was very rough. You are running this in the absolute mode. The gain is very high and the throttle is almost immediately involved in controlling the boost. FF and WGDC are out of whack. Still, your acceleration was very good.

For me, the turbohval3 was the best overall. It is the smoothest, steady valve action, and WGDC and FF curves nicely lined up.

Cops will grab you on that 4th gear run...

enjoy!

The KEpsi3 log was an absolute +6psi map. Tried mirroring map 3 by using absolute +6psi to see if there was any difference. So technically shouldn't that be the same as map 3?

And no cops on that road It's a long, abandoned road leading to a dead end and no one drives on it

Regards,
Vipin

[Turboh]

The KEpsi3 log was an absolute +6psi map. Tried mirroring map 3 by using absolute +6psi to see if there was any difference. So technically shouldn't that be the same as map 3?

And no cops on that road It's a long, abandoned road leading to a dead end and no one drives on it

Regards,
Vipin

I think they are not the same, regardless of boost. Map3 includes other settings, including timing, wgdc, ff etc to provide the best general performance.

Also, map 3 does auto adjustments....i do not think map 6 does. Auto adjust helps performance as things chance due to weather and gas..I think.

That road is perfect...

[VipinLJ]

I think they are not the same, regardless of boost. Map3 includes other settings, including timing, wgdc, ff etc to provide the best general performance.

Also, map 3 does auto adjustments....i do not think map 6 does. Auto adjust helps performance as things chance due to weather and gas..I think.

That road is perfect...

Ah gotcha. I did think there were other factors as well but I wasn't sure.

Also, how do you calculate acceleration? Rpm and what other factor? Change in rpm over a certain period of time?

And yes. It's my personal drag strip except that the roads aren't great or completely level. I do my runs on an uphill section.

Vipin

[Turboh]

Ah gotcha. I did think there were other factors as well but I wasn't sure.

Also, how do you calculate acceleration? Rpm and what other factor? Change in rpm over a certain period of time?

And yes. It's my personal drag strip except that the roads aren't great or completely level. I do my runs on an uphill section.

Vipin

Lol, beats my I 89 on and off ramps.

Yes, the average acceleration is ending-minus beginning rpm divided by the ending time. It is simply a ratio. The bigger the number the better your acceleration. Just track that for all your runs and you can quickly get an idea of how you are doing, power wise.

If you want to get exact, the timestamp is in 1/10 seconds. So on your calculator, take the difference between the ending and beginning mph, off the log sheet, and multiply by 1.467, and then divide the number by the ending time stamp divided by 10, and you will have the average ft/sec2 acceleration.

As far as maps, I have found Map 6, overall, to be the best of them all.

I liked seeing your runs. Terry always says that the throttle valve is part of the boost control system. You can watch that on your runs. But if boosts get too high too quickly it will close off. Similarly, the waste gate will control the boost rate and amount and close off as set by the PID control and safety settings. Throttle control for boost is difficult and slow compared to waste gate control just from looking at the size of the throttle plate itself. So the better the WGDC operates, the less the throttle plate has to get involved. Big changes in gain on the waste gate result in big boost increase rates, which the throttle plate will have to manage. They end up fighting each other. Hence roughness and other things. IMHO lol.

[VipinLJ]

Lol, beats my I 89 on and off ramps.

Yes, the average acceleration is ending-minus beginning rpm divided by the ending time. It is simply a ratio. The bigger the number the better your acceleration. Just track that for all your runs and you can quickly get an idea of how you are doing, power wise.

If you want to get exact, the timestamp is in 1/10 seconds. So on your calculator, take the difference between the ending and beginning mph, off the log sheet, and multiply by 1.467, and then divide the number by the ending time stamp divided by 10, and you will have the average ft/sec2 acceleration.

As far as maps, I have found Map 6, overall, to be the best of them all.

I liked seeing your runs. Terry always says that the throttle valve is part of the boost control system. You can watch that on your runs. But if boosts get too high too quickly it will close off. Similarly, the waste gate will control the boost rate and amount and close off as set by the PID control and safety settings. Throttle control for boost is difficult and slow compared to waste gate control just from looking at the size of the throttle plate itself. So the better the WGDC operates, the less the throttle plate has to get involved. Big changes in gain on the waste gate result in big boost increase rates, which the throttle plate will have to manage. They end up fighting each other. Hence roughness and other things. IMHO lol.

Ah gotcha. I knew how to calculate the time taken between two speeds but didn't know how you calculated acceleration from the logs.

And I agree. I've found map 6 to be the best too. I did try map 4 but I think I didn't give my car enough time to adapt. Probably why my log showed a very low boost (haven't posted it here because of that). Map 3 wasn't bad until I discovered map 6. Lol

And Terry asked me to change the duty bias on my last few runs. I did that and the throttle looks so much better!

[VipinLJ]

Hey guys

Quick question. I run around E25 (3.75gallons E85 and rest 93 for a full tank of ~15.6 gallons) regularly. I have a few bottles of Lucas octane booster lying in my garage that I bought before I found out about the benefits of E85. I was wondering if I could use those bottles in my car (with E85 in the tank). Would it help with the octane level? Or would it be better if I use it in one of my other cars? I don't want to let those bottles go to waste is all.

Regards,
Vipin

[sejin]

Lol, beats my I 89 on and off ramps.

Yes, the average acceleration is ending-minus beginning rpm divided by the ending time. It is simply a ratio. The bigger the number the better your acceleration. Just track that for all your runs and you can quickly get an idea of how you are doing, power wise.

If you want to get exact, the timestamp is in 1/10 seconds. So on your calculator, take the difference between the ending and beginning mph, off the log sheet, and multiply by 1.467, and then divide the number by the ending time stamp divided by 10, and you will have the average ft/sec2 acceleration.

As far as maps, I have found Map 6, overall, to be the best of them all.

I liked seeing your runs. Terry always says that the throttle valve is part of the boost control system. You can watch that on your runs. But if boosts get too high too quickly it will close off. Similarly, the waste gate will control the boost rate and amount and close off as set by the PID control and safety settings. Throttle control for boost is difficult and slow compared to waste gate control just from looking at the size of the throttle plate itself. So the better the WGDC operates, the less the throttle plate has to get involved. Big changes in gain on the waste gate result in big boost increase rates, which the throttle plate will have to manage. They end up fighting each other. Hence roughness and other things. IMHO lol.

How do the values of pidgain, ff/wastedgate adaptation, and duty bias affect the relationship between the wgdc curve and the ff curve?

[VipinLJ]

How do the values of pidgain, ff/wastedgate adaptation, and duty bias affect the relationship between the wgdc curve and the ff curve?

I'm sorry. I just saw this post for some reason. I'm not very knowledgeable about the relationship between them. You have to check the thread where the BMS guys have explained the various parameters in detail.

[Joshyb750]

1. This is borderline categorically untrue. The writing on the wall is quite clear when it comes to air filters. For a well designed filter, yes you WILL get lower pressure drop, thus better flow, thus less power loss, if you go from a "regular" filter to a "hi-flow" filter. But this is at the cost of filtering less stuff. This is just common sense. The problem of going down this route is the amount you can gain is soooooo small that it can't possibly be worth it for someone that OWNS their car.

Check out Air Filtration Test - Bob is the Oil Guy

There are plenty of properly conducted tests that show the pressure drop across OEM paper filters is only marginal (difference between stock and no filter in the above test was 0.07 psi !!).

Any test you see online claiming proven power gains is just BS as it's super easy to fudge figures should you choose to do that. Remember to never ask your barber if you need a haircut.

Likewise pod filters in cars nowadays has the same issue. Stock airboxes source air from the boundary layer or from the front bumper (actual cold air intakes) and minimize flow losses. The push towards efficiency we've seen in the past decade also serve to help us make more power. Pumping losses are losses that both economy and power optimizers strive to eliminate.

2. Ethanol definitely helps with timing and thus power yes. If you can get it definitely run it. Unfortunate I can't get any gas with ANY ethanol content in Hong Kong

High temps, high humidity = terrible power

3. Yeah if you already have a 30i and aren't looking to do more than simple mods I think the JB4 is perfect. If you're on a 20i platform I think a tune is a must as you get throttle closures that are hardcoded into the stock tune from the OEM as part of the "detuning" strategy they have AND the stock tune refuses to run rich even under load & WOT (all the 20i stock tunes i see never go below 14.2 AFR whereas 30i and 40i easily go to low 13s)

4. You're absolutely right

5&6. You sir are a gentleman and a scholar, check out this sheet I made A nerdy present for you all - N54Tech.com - International Turbo Racing Discussion

7&8. I wouldn't say it's the most important, and honestly you can't control your IAT so keeping it in mind is something you should do, but given you can't do anything about it you kinda just have to go

it's almost not possible to have a 10% power output difference because of IAT. Remember ideal gas law PV= NRT. For you to have 10% power difference at same boost you're roughly going to need 10% change in temps. That's next to impossible. It would be like going from 120f IAT to 179f IAT (remember temperature is measured from absolute 0 i.e -273 celcius or 0 kelvin)

9. With the EWG wire an absolute target map is feasible as JB4 has direct control over the wastegate but you should know how to "tune" in the sense of knowing what you need to watch out for before attempting anything. The additive boost (even custom additive boost) has the advantage of "relying" on your stock computer to adjust your boost target lower if it receives enough warning triggers from knock sensors and such.

WOT should be 85% of Stoich (on a blower at least. So 12.5-12.8. Screw gas mileage, save the car by running it rich and cooler

[Joshyb750]

Also, buying a aftermarket air filter you can personally clean and oil is worth more money over time. I don't think anyone buys them believing their butt dyno will know its there