[tylers1027]

Has anyone used the MX+ OBD reader? I got it to use to code Bimmercode. Today I installed my JB+ (left at the 3pm/+3psi default position). I do notice a small bump in power. I noticed on the MX+ app there's a boost gauge. Mostly it was reading in the 15psi range but a few times it was 20psi or above (the highest it read was 21.2psi). Is this boost gauge with the app inaccurate? I thought 21psi seemed a bit high for a JB+?

[DeathBlade]

If I understand right the module makes it underreport the actual boost level to the dme so the car makes more boost till it think it’s at the right level when in reality it’s now +3psi over because it’s under reported by 3. I think 20 is actual close to stock.

[VipinLJ]

With my JB4 on map 2 (+4psi), the app used to show a max of 21.6psi boost. But that was a spike during shifting. This was the JB4 app though, not bimmercode. Even with map 2 (+3psi), it used to show that spike. The actual boost levels weren't that high (just a spike during shifts). Not sure if that is what your app shows.
If there is a way to log, use that to find out what the boost levels are and find out when it shows the 20/21.2psi value.

And the stock boost isn't 20psi. In my car, stock max boost is around 14psi.

[tylers1027]

Originally Posted by VipinLJ

With my JB4 on map 2 (+4psi), the app used to show a max of 21.6psi boost. But that was a spike during shifting. This was the JB4 app though, not bimmercode. Even with map 2 (+3psi), it used to show that spike. The actual boost levels weren't that high (just a spike during shifts). Not sure if that is what your app shows.
If there is a way to log, use that to find out what the boost levels are and find out when it shows the 20/21.2psi value.

And the stock boost isn't 20psi. In my car, stock max boost is around 14psi.

Thanks for the response! This seems similar. The 20/21psi was popping up right when I pushed down the throttle briefly; not even at high RPM's or anything. And for the screenshot I posted; it's not from the actual Bimmercode app. I bought the MX+ blue tooth OBD adapter for the purpose of coding Bimmercode, but the MX+ has it's own standalone app with all the gauges etc. It also had a 0-60mph & 1/4 mile time tracker that I haven't got the chance to try yet.

[VipinLJ]

Originally Posted by tylers1027

Thanks for the response! This seems similar. The 20/21psi was popping up right when I pushed down the throttle briefly; not even at high RPM's or anything. And for the screenshot I posted; it's not from the actual Bimmercode app. I bought the MX+ blue tooth OBD adapter for the purpose of coding Bimmercode, but the MX+ has it's own standalone app with all the gauges etc. It also had a 0-60mph & 1/4 mile time tracker that I haven't got the chance to try yet.

Ah gotcha. Then it must be the boost spiking. I'd still suggest you take a log. Just to make sure timing and AFRs and boost are fine. Because I've learned that fuel quality can be a huge variable that can causing timing drops. It can happen with the JB+ too.

I have the OBD LX and app but it's been ages since I used it. The values it shows for performance will most probably be pulled from the ECU. It won't be perfect but it can be a good before and after (because the BMW ECU tends to show a higher speed compared to real time GPS speed; for example, my car with a custom map 6 does 0-60 in around 4.4-4.5s whereas the app says it is 4.1s).

[tylers1027]

Here's some logs I got; hope these can help. For both of these screenshots I was in 4th (or 5th gear). I punched it around 2500RPM and went to a little over 4500RPM. You can see right when I floor it boosts jumps to over 22psi @ 2500RPM. From 2500-3500RPM the boost slowly drops from 22psi down to 18psi and then holds steady at 18psi after 3500RPM. The A/F ration remains steady between 14-15.

I'm gonna take off the JB+ and see what the boost levels look like with it off. I'm a little freaked out this thing is showing 22+ psi on a completely stock engine with the JB+ set in the 3pm (+3psi) position. I read online stock psi is around 13psi so was expecting 16psi with the JB+; not 18-22psi.

Car feels great. Pulls hard, no sputtering or cutting out, no check engine lights. Just mostly worried of doing damage with too high of boost. Any thoughts?

[tylers1027]

Originally Posted by VipinLJ

Ah gotcha. Then it must be the boost spiking. I'd still suggest you take a log. Just to make sure timing and AFRs and boost are fine. Because I've learned that fuel quality can be a huge variable that can causing timing drops. It can happen with the JB+ too.

I have the OBD LX and app but it's been ages since I used it. The values it shows for performance will most probably be pulled from the ECU. It won't be perfect but it can be a good before and after (because the BMW ECU tends to show a higher speed compared to real time GPS speed; for example, my car with a custom map 6 does 0-60 in around 4.4-4.5s whereas the app says it is 4.1s).

Alright I just took the JB+ out and tried this again. With the JB+ out I did a full throttle run from 2500rpm-5500rpm. The boost was steady at 16psi the entire 2500rpm-5500rpm; whereas the JB+ shoots up to around 22.5psi for 1000rpm and then drops down to about 18psi after that. I'm not sure how accurate this gauge is; but with the JB+ showing almost 23psi and without showing 16psi max; that's almost a 7psi increase (but only supposed to be 3?)

[VipinLJ]

So looks like boost spikes to me. Those happen even in my car with the jb4. It used to be worse with the older firmware and has become better with the new updates. I still get spikes of around 21.6psi. Those spikes are for a very short period of time. I haven't ever logged with the JB+ so I don't know how it is. I'd be more concerned about timing that these boost spikes. See if you can log timing on all cylinders?

And your boost stock is around 16psi? So 18psi is only 2psi more. Don't worry about the spike. My car doesn't boost as much. Stock it only boosts to around 13-14psi. Highest is 14.6psi or so iirc. Doesn't even touch 15psi.

[tylers1027]

Originally Posted by VipinLJ

So looks like boost spikes to me. Those happen even in my car with the jb4. It used to be worse with the older firmware and has become better with the new updates. I still get spikes of around 21.6psi. Those spikes are for a very short period of time. I haven't ever logged with the JB+ so I don't know how it is. I'd be more concerned about timing that these boost spikes. See if you can log timing on all cylinders?

And your boost stock is around 16psi? So 18psi is only 2psi more. Don't worry about the spike. My car doesn't boost as much. Stock it only boosts to around 13-14psi. Highest is 14.6psi or so iirc. Doesn't even touch 15psi.

Thanks for letting me know! I'm not sure how to check timing on the app? I'm sure it has it but I don't know which filter that would be?

I thought I read online stock psi was 13 so was surprised to see I'm 16psi without the jb+. Since I'm at sea level right by the water, or since it's winter and very cold Temps maybe that raises the boost?

So it sounds like I'm OK with the 1 second or so boost spike to 22psi since it's dropping down to 18-19psi after the initial spike (2-3psi over stock)? Those charts show a lot. It seems the jb+ has a large initial boost spike where the stock boost is pretty much flat.

[VipinLJ]

Originally Posted by tylers1027

Thanks for letting me know! I'm not sure how to check timing on the app? I'm sure it has it but I don't know which filter that would be?

I thought I read online stock psi was 13 so was surprised to see I'm 16psi without the jb+. Since I'm at sea level right by the water, or since it's winter and very cold Temps maybe that raises the boost?

So it sounds like I'm OK with the 1 second or so boost spike to 22psi since it's dropping down to 18-19psi after the initial spike (2-3psi over stock)? Those charts show a lot. It seems the jb+ has a large initial boost spike where the stock boost is pretty much flat.

See if there's something like ignition timing or cylinder timing or timing correction?

And try and get a proper log to see how it is.
1. Car in sport/sport plus
2. Gear shifter in manual (not D/S)
3. Traction control in sport or off
4. RPMs at around 2-2.5k
5. Car in 3rd gear
6. Go WOT from there till around 6.5k rpms and then upshift to 4th. Stay in 4th for a second or so before backing off
Make sure it's a nice long empty roads since you'll be doing pretty decent speeds by the time you're done getting a logging run.

And yes. The B46/48 is weird. I know some people have cars that boost much higher than mine stock. Mine is only around 13-14 max. Someone else has one that boosts to 16-18psi iirc. Idk why the variation but yeah.

[tylers1027]

Originally Posted by VipinLJ

See if there's something like ignition timing or cylinder timing or timing correction?

And try and get a proper log to see how it is.
1. Car in sport/sport plus
2. Gear shifter in manual (not D/S)
3. Traction control in sport or off
4. RPMs at around 2-2.5k
5. Car in 3rd gear
6. Go WOT from there till around 6.5k rpms and then upshift to 4th. Stay in 4th for a second or so before backing off
Make sure it's a nice long empty roads since you'll be doing pretty decent speeds by the time you're done getting a logging run.

And yes. The B46/48 is weird. I know some people have cars that boost much higher than mine stock. Mine is only around 13-14 max. Someone else has one that boosts to 16-18psi iirc. Idk why the variation but yeah.

Alright I finally found how to add items to the csv log! I added the A/F ratio, boost level, engine power/torque, engine RPM/vehicle speed, throttle position, and "fuel injection timing". The only other item I can find is "ignition timing advance for #1 cylinder" but I don't see the other cylinders listed. Will give this log a try tonight after work.

Also that seems so strange some stock cars hitting 13psi while others hitting 18psi stock. Would that mean the 18psi stock car is getting faster wear on the engine/turbo than the other stock car of 13psi? And would the 18psi stock car be faster than the 13psi; even though both cars are exactly the same and both stock?

[VipinLJ]

Originally Posted by tylers1027

Alright I finally found how to add items to the csv log! I added the A/F ratio, boost level, engine power/torque, engine RPM/vehicle speed, throttle position, and "fuel injection timing". The only other item I can find is "ignition timing advance for #1 cylinder" but I don't see the other cylinders listed. Will give this log a try tonight after work.

Also that seems so strange some stock cars hitting 13psi while others hitting 18psi stock. Would that mean the 18psi stock car is getting faster wear on the engine/turbo than the other stock car of 13psi? And would the 18psi stock car be faster than the 13psi; even though both cars are exactly the same and both stock?

Fuel injection timing might be it. I checked my app and also saw only injection timing advance in #1 cylinder. No idea about the others.

And the stock turbo can handle 20psi+. I think someone who's into this engine and probably has one of the fastest G20 330is in the world said it was around 22-24 iirc. But yes. More boost means faster wear and tear though stock for stock, were looking at a couple hundred-thousand miles. And yes. Cars that boost higher from the factory are faster. Probably explains why my car has a lower 0-60 time than cars tested by magazines and the likes. Hehe. But yea. Get a decent log using steps i mentioned in the previous post and we can take a look at that to see how the JB+ works.

[tylers1027]

Originally Posted by VipinLJ

Fuel injection timing might be it. I checked my app and also saw only injection timing advance in #1 cylinder. No idea about the others.

And the stock turbo can handle 20psi+. I think someone who's into this engine and probably has one of the fastest G20 330is in the world said it was around 22-24 iirc. But yes. More boost means faster wear and tear though stock for stock, were looking at a couple hundred-thousand miles. And yes. Cars that boost higher from the factory are faster. Probably explains why my car has a lower 0-60 time than cars tested by magazines and the likes. Hehe. But yea. Get a decent log using steps i mentioned in the previous post and we can take a look at that to see how the JB+ works.

FYI response I got from BMS was "Whatever you are using to read the boost is not reading the actual boost as JB+ tricks the ECU into making more boost. You are reading OEM boost from the ECU".

I may just put the JB+ back on. The car ran great with it in and I was probably just over-worrying. I haven't read of any threads of anyone having any issues with the JB+ so I think I was just over-thinking it.

[VipinLJ]

Originally Posted by tylers1027

FYI response I got from BMS was "Whatever you are using to read the boost is not reading the actual boost as JB+ tricks the ECU into making more boost. You are reading OEM boost from the ECU".

I may just put the JB+ back on. The car ran great with it in and I was probably just over-worrying. I haven't read of any threads of anyone having any issues with the JB+ so I think I was just over-thinking it.

Wait so BMS is saying your car is making 20psi stock? That's crazy high for a stock car. Probably the highest boosting G30 330i in history! Did you ask them why the difference then between JB+ on and off with regards to the app values?

[tylers1027]

Originally Posted by VipinLJ

Wait so BMS is saying your car is making 20psi stock? That's crazy high for a stock car. Probably the highest boosting G30 330i in history! Did you ask them why the difference then between JB+ on and off with regards to the app values?

They said "since ECU is not flashed, you can add 3-4psi on top of what you read and that will be the real boost".

I didn't write back; I didn't want to keep bugging the guy (Ando @ BMS). But if I add 3-4 psi on top of 22psi, that would be 25-26psi.

I tried to read up some more online; and I think the ECU may be adding in that atmosphere pressure or something so it reads high (I'm not sure what the atmospere pressure is that would get backed out).

[patnaik]

Subtract 14.7 from the absolute pressure (psia) to get psi.

[VipinLJ]

Originally Posted by tylers1027

They said "since ECU is not flashed, you can add 3-4psi on top of what you read and that will be the real boost".

I didn't write back; I didn't want to keep bugging the guy (Ando @ BMS). But if I add 3-4 psi on top of 22psi, that would be 25-26psi.

I tried to read up some more online; and I think the ECU may be adding in that atmosphere pressure or something so it reads high (I'm not sure what the atmospere pressure is that would get backed out).

That is so weird. Unfortunately, my knowledge is limited. I can ask around in our tuned B46/48 group. We have a few knowledgeable people there who might be able to help.

[tylers1027]

Originally Posted by VipinLJ

That is so weird. Unfortunately, my knowledge is limited. I can ask around in our tuned B46/48 group. We have a few knowledgeable people there who might be able to help.

I'll try that absolute pressure - 14.7 too and see what I can get. We did get 2 feet of snow yesterday so it will be a bit before I can get some test runs in lol!

[njfoses]

Originally Posted by VipinLJ

That is so weird. Unfortunately, my knowledge is limited. I can ask around in our tuned B46/48 group. We have a few knowledgeable people there who might be able to help.

Is that a FB group?

[VipinLJ]

Originally Posted by tylers1027

I'll try that absolute pressure - 14.7 too and see what I can get. We did get 2 feet of snow yesterday so it will be a bit before I can get some test runs in lol!

So I spoke to a few people. One of them, like I've mentioned before either here or somewhere else, has a crazy tuned G20 330i and he's knowledgeable. He said what you see is normal.
To know for sure that is isn't an issue, we need to get a good log like I mentioned before. Random runs or WOT won't help.

Originally Posted by njfoses

Is that a FB group?

No sir. It's a WhatsApp group. Anyone is free to join. Mainly tuned B46/48s. Clever guys there who can read logs and explain stuff and help if needed.