[High Flier]

The benefits of JB4 are appealing. Does anyone have any experience using JB4 with an MPPSK B58?

1. Would get any more total power/torque than I am already getting with my stock MPPSK 340iX?
   
2. Would I get more low-end power/torque than I am already getting with my stock MPPSK 340iX?
   
3. Would the sport displays then be inaccurate or misleading with a tune like this?
   
4. Could I still get a power boost with the exhaust valves closed?

[riskmaker76]

1. Yes - but your mileage will vary - Issues are mostly around octane / quality of fuel and the car itself. For my car with the quality of gas in the area (93 octane) my max is 3PSI in the winter and 2 PSI in the summer (Map 6) above what ever the MPPSK puts out at that moment (it varies due to many factors, one day its base is 10 PSI another its 12 PSI). More than that my timing drops too much and affects drivability and performance. Map 1 works fine in the winter but too much for the Summer IMO.

2. Yes as 1
3. Misleading - in fact HP will read lower (but Dyno says otherwise).
4. Yes for sure.. in comfort mode its the same difference; especially when you step on it... its much more noticeable though with the throttle curve of Sport / Sport +

All in all your probably going to add 15 - 30 HP to the MPPSK without adding octane booster or E85 with the JB4. You can gain more with more octane...

[bmw5858]

Originally Posted by riskmaker76

1. Yes - but your mileage will vary - Issues are mostly around octane / quality of fuel and the car itself. For my car with the quality of gas in the area (93 octane) my max is 3PSI in the winter and 2 PSI in the summer (Map 6) above what ever the MPPSK puts out at that moment (it varies due to many factors, one day its base is 10 PSI another its 12 PSI). More than that my timing drops too much and affects drivability and performance. Map 1 works fine in the winter but too much for the Summer IMO.

2. Yes as 1
3. Misleading - in fact HP will read lower (but Dyno says otherwise).
4. Yes for sure.. in comfort mode its the same difference; especially when you step on it... its much more noticeable though with the throttle curve of Sport / Sport +

All in all your probably going to add 15 - 30 HP to the MPPSK without adding octane booster or E85 with the JB4. You can gain more with more octane...

And when I've talking with other person who have JB4 with MPPSK, guys are saying they can run map 2 (additive 4psi over the 2 psi added from MPPSK) which is the equivalent of the map 3 on jb4 (additive 6 psi over stock) and there is no issue, car is running great! Depending on octane yes this is a major fact!

Here in Canada we have access to 94 octane, so I don't think I'll have problem running map 2 + MPPSK but I'll need to make some log to verify.

One thing for sure,

A stock car + JB4 map 3 will have as much power as the jb4 map 2 + MPPSK.

[riskmaker76]

Every car is different - the data is the data - doesnt lie. My car just doesnt like anything more then 3psi in general and even less in the summer. Wish it wasnt the case.

Keep in mind also, can I do map 2 --- Sure... Will the car drive - sure.. will I see random performance boost - yep... But more often then not, I will also see timing flat or target not holding (maps 1 - 3 adjusting your target based on many factors). That means drivability is also going to suffer ever time the JB4 adjust - because the Cars computer will then adjust (it sees the added boost, thus drop in timing if you dont have enough octane, with then causes and adjustment to the JB4... etc. etc.). As long as timing holds everything is perfect...

So generally your right, some have had success... yet some like me have not had as much success... all in all JB4 is worth it even for the 2PSI above stock.. its a noticeable difference.. though 3 or 4 is a much much bigger difference. If you have the octane / quality of gas, I say do it.

Anyway, you can play with it on map 6 which gives you full tunability.

Originally Posted by bmw5858

And when I've talking with other person who have JB4 with MPPSK, guys are saying they can run map 2 (additive 4psi over the 2 psi added from MPPSK) which is the equivalent of the map 3 on jb4 (additive 6 psi over stock) and there is no issue, car is running great! Depending on octane yes this is a major fact!

Here in Canada we have access to 94 octane, so I don't think I'll have problem running map 2 + MPPSK but I'll need to make some log to verify.

One thing for sure,

A stock car + JB4 map 3 will have as much power as the jb4 map 2 + MPPSK.

[MaximusJ]

Originally Posted by bmw5858

A stock car + JB4 map 3 will have as much power as the jb4 map 2 + MPPSK.

I have to disagree with this. Yes they will have the same boost; if you dont look at the digits; but the MPPSK car still have an advantage that the stock one doesnt have; the exhaust system.

I agree its not a huge advantage, but i'd put my money on the mppsk car any day.

[riskmaker76]

There is also a known fueling advantage - Terry has confirmed this.

Originally Posted by MaximusJ

I have to disagree with this. Yes they will have the same boost; if you dont look at the digits; but the MPPSK car still have an advantage that the stock one doesnt have; the exhaust system.

I agree its not a huge advantage, but i'd put my money on the mppsk car any day.

[MaximusJ]

In a perfect world, we would need to compare logs on a same car Stock vs. Stock w/MPPSK vs. JB4 vs. JB4/MPPSK But the latter takes the cake for sure.

How much PSI total with MPPSK/JB4 riskmaker76?

[riskmaker76]

I generally see 14 - 15 PSI on Map 1 or with 3PSI Map 6 defined in the Winter..

The same settings yield 16 - 17 PSI in the summer - Why? because the BMW computer sets a higher base target in the warmer weather ---- I have no idea why it does that... again this is confirmed with BMS. They are seeing the same thing... The issue is when the PSI is too much timing will drop considerably - at least on my car. Some others have no issues at 16 PSI or 17 PSI with 93 octane... My limit is about 15 PSI... I have yet to install the EWG wires to define absolute values - that should help provide consistency... for now I do additive values on Map 6 using what I learned from Map 1. I set 3 psi to 5k... then ramp down to 2psi up to 7k. That seems to allow my timing to gradually increase as RPMs increase with no drops.... --- in the summer - I have to start that ramp down of PSI at 4k. Cant even use Map 1 in the dead of summer - runs too inconsistent for my liking (without octane booster).

Originally Posted by MaximusJ

In a perfect world, we would need to compare logs on a same car Stock vs. Stock w/MPPSK vs. JB4 vs. JB4/MPPSK But the latter takes the cake for sure.

How much PSI total with MPPSK/JB4 riskmaker76?

[CruzM3]

I have a 340i w/ MPPSK (rwd) and I have JB4 on map 3 98ron fuel which is about 93 octane in the US. The car runs great and is an absolute beast. The gas quality here in Europe is usually better but fueling is the key. If you use quality fuel you won't have issues running JB4 and will see gains in performance.

[bradsm87]

What fuel are you running? If 91, don't bother. If 93:

1) yes
2) yes
3) yes
4) that would be a bad idea

[bradsm87]

Originally Posted by bmw5858

A stock car + JB4 map 3 will have as much power as the jb4 map 2 + MPPSK.

Possibly buy WAY less dodgy in doing so. The MPPSK + lower map is MUCH safer. Fuel trims aren't pushed so far, leaving more safety margin. The DME is more aware of increased boost which is good for MANY reasons. If auto, the transmission will perform better by having a closer-to-real torque figure fed to it.

[High Flier]

Originally Posted by bradsm87

What fuel are you running? If 91, don't bother. If 93:

1) yes
2) yes
3) yes
4) that would be a bad idea

Yes, 93 only.

4) Why is it a bad idea? Any risk of damage or just counterproductive.

[Bullitt1841]

Originally Posted by High Flier

The benefits of JB4 are appealing. Does anyone have any experience using JB4 with an MPPSK B58?

1. Would get any more total power/torque than I am already getting with my stock MPPSK 340iX?
   
2. Would I get more low-end power/torque than I am already getting with my stock MPPSK 340iX?
   
3. Would the sport displays then be inaccurate or misleading with a tune like this?
   
4. Could I still get a power boost with the exhaust valves closed?

1. If tuned properly with enough octane, yes.
2. If tuned properly with enough octane, yes.
3. Probably. But who cares? These are a gimmick. Recording on a dyno is more fun, more accurate, and more informative. Use a GPS-based performance timer to get the best real world data that actually means something.
4. I've gone WOT many times with the valves closed via the JB4. I can't tell if there's any measurable difference, but intuition tells me it is harder on the turbo at higher boost levels.

[bradsm87]

Originally Posted by High Flier

Yes, 93 only.

4) Why is it a bad idea? Any risk of damage or just counterproductive.

It's already pushing things running a JB4 at all. Combining that with increasing exhaust back pressure makes things worse.

[wassy4]

Originally Posted by bradsm87

It's already pushing things running a JB4 at all. Combining that with increasing exhaust back pressure makes things worse.

People run jb4 on completely stock exhaust with no issues, and a piggyback like jb4 does not push things at all. Jb4 + stage 3 turbos + meth pushes this engine on current limitations.

[bradsm87]

Originally Posted by wassy4

People run jb4 on completely stock exhaust with no issues, and a piggyback like jb4 does not push things at all. Jb4 + stage 3 turbos + meth pushes this engine on current limitations.

Stock DME opens the valve at high load. User was asking about having it forced closed.

A piggyback like JB4 absolutely does push things. It can't change the lean stock boost AFR target when it's actually running higher boost. It relies on knock detection as it can't control the ignition timing target. The DME isn't aware of the extra boost so relies on fuel trims to try and meet the already-lean AFR target.

Larger turbo and meth makes things more safe, not less safe. Pushing high boost with the stock turbos at low RPM and the DME having no idea it's happening due to piggyback is what can kill rods. Pushing boost at high RPM with the tiny stock turbos and the DME having no idea what's going on with a lean AFR and too aggressive timing target also kills engines quickly.

[wassy4]

Originally Posted by bradsm87

Stock DME opens the valve at high load. User was asking about having it forced closed.

A piggyback like JB4 absolutely does push things. It can't change the lean stock boost AFR target when it's actually running higher boost. It relies on knock detection as it can't control the ignition timing target. The DME isn't aware of the extra boost so relies on fuel trims to try and meet the already-lean AFR target.

Larger turbo and meth makes things more safe, not less safe. Pushing high boost with the stock turbos at low RPM and the DME having no idea it's happening due to piggyback is what can kill rods. Pushing boost at high RPM with the tiny stock turbos and the DME having no idea what's going on with a lean AFR and too aggressive timing target also kills engines quickly.

Pretty sure larger turbos + meth don't make it safer, still have to deal with the issues you listed. Even Fuel-It sent out a warning about running anything more than meth. Not one mention about piggybacks being unsafe though. Of course a piggyback will push things, happens with anything you do over stock, but they're all fairly conservative. Not gonna hurt anything, and the valve will act the same as stock - it's MPPSK after all.

[bradsm87]

Originally Posted by wassy4

Pretty sure larger turbos + meth don't make it safer, still have to deal with the issues you listed. Even Fuel-It sent out a warning about running anything more than meth. Not one mention about piggybacks being unsafe though. Of course a piggyback will push things, happens with anything you do over stock, but they're all fairly conservative. Not gonna hurt anything, and the valve will act the same as stock - it's MPPSK after all.

MPPSK is much safer because the DME is aware of the higher load and has different AFR and timing targets to suit plus even different knock sensor calibration and many, many more unknown safeties.

Upgraded turbo means lower exhaust back pressure and lower IAT so definitely safer when not running lots more boost.

I understand that the DMEs are not yet tuneable so some compromise has to be made to get more power. I'd happily run MPPSK + Map 1 or even upgraded turbo with a conservative additive Map 6 map with gradual increase in additive over RPM. Stock flash + map 3 is just absolute madness though.

[blckz06]

Originally Posted by bradsm87

MPPSK is much safer because the DME is aware of the higher load and has different AFR and timing targets to suit plus even different knock sensor calibration and many, many more unknown safeties.

Upgraded turbo means lower exhaust back pressure and lower IAT so definitely safer when not running lots more boost.

I understand that the DMEs are not yet tuneable so some compromise has to be made to get more power. I'd happily run MPPSK + Map 1 or even upgraded turbo with a conservative additive Map 6 map with gradual increase in additive over RPM. Stock flash + map 3 is just absolute madness though.

Interesting view. I'm running MPPSK, dp, intake and 93 octane. Terry has reviewed my map 3 logs multiple times and was certainly comfortable with me staying on map 3. Both afr and timing looked reasonable.

[wassy4]

Originally Posted by blckz06

Interesting view. I'm running MPPSK, dp, intake and 93 octane. Terry has reviewed my map 3 logs multiple times and was certainly comfortable with me staying on map 3. Both afr and timing looked reasonable.

Yep, there's thousands of people that have been running jb4 map 3 and map 5 for almost two years with no issue. MPPSK really doesn't make a difference except for the initial power and fueling advantage.

[Mike@N54Tuning.com]

Originally Posted by wassy4

Yep, there's thousands of people that have been running jb4 map 3 and map 5 for almost two years with no issue. MPPSK really doesn't make a difference except for the initial power and fueling advantage.

+1

We have lots of customers with it and JB4..

Mike

[bradsm87]

Originally Posted by wassy4

Yep, there's thousands of people that have been running jb4 map 3 and map 5 for almost two years with no issue. MPPSK really doesn't make a difference except for the initial power and fueling advantage.

No issue? In most tuner's books, no issue means no leaner than 12.5:1, no constant knock detections and fuel trims +/- 5%. Just because the car seems to drive OK does not mean no underlying issues. Any B58 JB4 on map 3 is going to be constantly riding knock detections unless you're running race fuel and it's still running the crazy lean factory AFR target. It's also going to have its fuel trims pretty much maxed out and likely completely maxed out in some spots. You're much better off running less boost and enabling it to run a bit more timing.