[Fuel-It!]

Originally Posted by VipinLJ

A few people have been getting CELs with the JB+ recently (though on the B46 engine). Probably a defective batch? Did you contact BMS?

There was a batch of around 50 JB+ systems that had the wrong firmware loaded. You know you got one of those from the bad batch if you install it and get a CEL right away. If you have one just email them and they will send a replacement and a return label for the faulty one.

[Fuel-It!]

Originally Posted by tarrant64

Well I put the JB+ back in (at position 3/50%) after having it stock for a bit and it seems after awhile it just throws the check engine/code again.

My guess is it won't matter what setting I have the JB+ set at - something with the '21 motor after awhile learns that it's off and refuses to be ok with it.

Car still drives fine, just throws a code. Honestly annoyed with it and it's keeping me from upgrading to something like the JB4, because there isn't really any ability to tell the ECU not to freak out.

Not really sure what my options are, but going to search around see if any others with a 21 are having the issue.

It's not your car it's the JB+. See my post above. They figured out the problem yesterday and can swap it for one with the correct firmware BMW firmware loaded.

[tarrant64]

Originally Posted by Fuel-It!

It's not your car it's the JB+. See my post above. They figured out the problem yesterday and can swap it for one with the correct firmware BMW firmware loaded.

Thanks for that information!

[tarrant64]

Well got my JB+ replacement, tried that out - and back to where I started. Periodic check engine light.

I don't know if it's just a matter of Burger not updating the software on it to address any differences with the newer 2021 mild-hybrid (48-volt) or what, and just assuming if it was good for the 2020 it's fine for the 2021. I have the "fixed" JB+ now, but it still throws the check engine code.

I'll reach out to their support, but at this point a little irritated but is what it is.

[RTPenland]

Originally Posted by tarrant64

Well got my JB+ replacement, tried that out - and back to where I started. Periodic check engine light.

I don't know if it's just a matter of Burger not updating the software on it to address any differences with the newer 2021 mild-hybrid (48-volt) or what, and just assuming if it was good for the 2020 it's fine for the 2021. I have the "fixed" JB+ now, but it still throws the check engine code.

I'll reach out to their support, but at this point a little irritated but is what it is.

Our cars have a very sophisticated DME (computer) it's not surprising that trying to trick it with something that is on par with something you could pick up at radio shack (back in the day) throws an error code

I would suggest a flash by the majors (MHD, BM3, Mission) piggyback vs flash all detectable so just go with a flash

[tarrant64]

Originally Posted by RTPenland

Our cars have a very sophisticated DME (computer) it's not surprising that trying to trick it with something that is on par with something you could pick up at radio shack (back in the day) throws an error code

I would suggest a flash by the majors (MHD, BM3, Mission) piggyback vs flash all detectable so just go with a flash

Flash > piggyback is not the problem or a matter of understanding that. Flash isn't an option for the 2021 DME's. It's locked, so JB4/JB+/Racechip are really the only options right now.

I turned down the JB+ and will continue to keep testing for now. If anything, the JB+ needs software updated to deal with changes in the 2021 latest DME. The higher the boost is set, the slower the car gets (butt dyno) and shifts are slow. This was determined before, but since it was clarified there were a number of jB+ units shipped out that incorrect firmware, set it to max again for some testing. I'm dialing it back to see what's good or not.

For a short period of time during 'learning' it seems OK, then it gradually gets worse then throws a code. So I 100% agree, it's a sophisticated DME that after a certain amount of parameters are hit after 'x' time/miles, it's either OK with it or it isn't. In this case it's not OK with it.

[Fuel-It!]

If the JB+ is giving problems on the new hybrid model even at the lower settings then maybe it just needs something more advanced like a JB4. They offer 100% trade up credit.

[mike@x-ph.com]

Originally Posted by Fuel-It!

If the JB+ is giving problems on the new hybrid model even at the lower settings then maybe it just needs something more advanced like a JB4. They offer 100% trade up credit.

[cjpp78]

I have been running a jb+ on a 2021 M340 for several months. The car is noticeably faster and has better low end grunt. I have the jb+ maxed out but I also run a E30 mix with 93 octane. I really feel that the M340 probably responds to the added boost better with added octane.. considering the car runs more boost stock than previous B58 powered cars. I've trapped as high as 117mph in quarter mile so far with nothing but JB+ maxed out and E30 mix. Stock everything else , even air filter.

[GD1981]

Originally Posted by cjpp78

I have been running a jb+ on a 2021 M340 for several months. The car is noticeably faster and has better low end grunt. I have the jb+ maxed out but I also run a E30 mix with 93 octane. I really feel that the M340 probably responds to the added boost better with added octane.. considering the car runs more boost stock than previous B58 powered cars. I've trapped as high as 117mph in quarter mile so far with nothing but JB+ maxed out and E30 mix. Stock everything else , even air filter.

This is very true^^

I have a JB4 and to really get the most out of it with the M340 (I have a 2021), any user must introduce some corn juice into the equation, else as you run more boost timing will get pulled.

I run about an E25 mix on Map 3 (no other mod) and it is noticeably quicker, with dragy concurring.


Side note- I just learned the other day the M340i User Manual states that we can use up to E25 on the vehicle

[cjpp78]

Originally Posted by GD1981

This is very true^^

I have a JB4 and to really get the most out of it with the M340 (I have a 2021), any user must introduce some corn juice into the equation, else as you run more boost timing will get pulled.

I run about an E25 mix on Map 3 (no other mod) and it is noticeably quicker, with dragy concurring.


Side note- I just learned the other day the M340i User Manual states that we can use up to E25 on the vehicle

JB4
Nice! Didn't know that was in the manual. yeah I see a lot of post of people talking about poor performance on the M340 with JB+/JB4 but most of the time they aren't using a higher octane than 93 pump, 91 a lot of times. These cars run 15psi stock so jb+ or jb4 is taking these up to around 20psi. I think now especially in the summer heat, elevated boost levels without additional octane just causes timing to be pulled. Then people say the jb+/ jb4 doesn't work or makes car slower... The trans does shift slower due to torque limiters being hit but the engine makes more power if you have the octane for the elevated boost levels. This is why torque limits are hit in the first place.
The original poster said his car is slower above 100mph. Probably so because it has heated up by that speed and started pulling timing due to octane not cutting it..My car pulls like a freight train to redline and I have recorded 117mph in the quarter mile. So on a stock car with a piggyback like these I think octane makes the difference

[GD1981]

Originally Posted by cjpp78

JB4
Nice! Didn't know that was in the manual. yeah I see a lot of post of people talking about poor performance on the M340 with JB+/JB4 but most of the time they aren't using a higher octane than 93 pump, 91 a lot of times. These cars run 15psi stock so jb+ or jb4 is taking these up to around 20psi. I think now especially in the summer heat, elevated boost levels without additional octane just causes timing to be pulled. Then people say the jb+/ jb4 doesn't work or makes car slower... The trans does shift slower due to torque limiters being hit but the engine makes more power if you have the octane for the elevated boost levels. This is why torque limits are hit in the first place.
The original poster said his car is slower above 100mph. Probably so because it has heated up by that speed and started pulling timing due to octane not cutting it..My car pulls like a freight train to redline and I have recorded 117mph in the quarter mile. So on a stock car with a piggyback like these I think octane makes the difference

Yep, have noticed the tranny shift a tad slower myself .. proof of the power bump.
That said - Im loving that corn in the gas tank lol:

[cjpp78]

Originally Posted by GD1981

Yep, have noticed the tranny shift a tad slower myself .. proof of the power bump.
That said - Im loving that corn in the gas tank lol:

Same here, it's like a different animal on the E30 mix vs straight 93 pump.

[G_B58]

So the tranny lags a bit with the jb+?

[tarrant64]

Originally Posted by G_B58

So the tranny lags a bit with the jb+?

YMMV and it depends on how turned up it is. It is likely pulling timing as mentioned above - meaning quality of fuel will matter here. My take away/personal experience so far after a couple months:

- JB+ at max results in noticeable low-rpm throttle delay/lag and rough shifts - diminishing returns really at higher speeds.

- JB+ at medium results in noticeable performance gains, light low-rpm throttle delay/lag, most shifts are good.

I tracked the car with the JB+ - it works. For the money, it is what it is. On the fence upgrading to the JB4 but I'm tempted. For the weeks I ran without the JB+ on the car does drive better, but seems slower once you're moving and punch it.

It's complicated lol.

[G_B58]

So if octane is added it fixes the shifts or at least improves them? Like adding e85 or running 94 oct?

I actually have one, been sitting at home for a few weeks now lol. Just been debating putting it on after reading the mission post, explaining how bmw tracks the cars performance to see if it's been tuned or a piggyback. I've got a dp, exhaust, and inlet, which give a nice improvement in throttle and power so im debating if it's really worth the risk of adding the jb+, especially if it will only make a small difference.

[chenry]

Originally Posted by G_B58

So if octane is added it fixes the shifts or at least improves them? Like adding e85 or running 94 oct?

I actually have one, been sitting at home for a few weeks now lol. Just been debating putting it on after reading the mission post, explaining how bmw tracks the cars performance to see if it's been tuned or a piggyback. I've got a dp, exhaust, and inlet, which give a nice improvement in throttle and power so im debating if it's really worth the risk of adding the jb+, especially if it will only make a small difference.

As you've mentioned gone are the days that a piggyback (by any manufacturer) is undetectable whether it is found out before hand and flagged or discovered after a failure by reverse engineering. This same topic is also being discussed in the G80 forum...and the consensus is the same

So that's the bad news. The good news is well designed piggybacks and flashes have not created issues for the B58 since it was first brought to market in 2016/17. That said - if you are going to go down the tuning path I personally wouldn't bother with a box when you can get an oem like experience with a flash. Yes I know for 21 owners a flash is not an option (just yet) but I'm not sure if I would even bother with a box knowing what is right around the corner.

If nothing else buy the box from forum sponsor Mike at x-ph.com in that he offers money back on his box sales. But you already have the JB+ so plug it in and play around with it - the b58 and box combo hate 91 but that shouldn't be an issue with you in Canada (I don't think).

**disclaimer** former box owner and current huge MP fan here - just had my car (2020 M340) at california speedway a couple weeks back for my 50th birthday and car simply wouldn't stop pulling on the banked oval as I passed 145+ (car had way more to give I did not) and then drove it home in traffic like it had been sitting at home all day and/or just out on casual grocery runs

[G_B58]

I actually bought it from Mike, as well as the intake muffler delete and ftp inlet, only regret was paying extra for shipping from the post office, must have been tired cause I didn't pay close attention and assumed or was ups and not usps lol. Funny enough I thought I was being clever get the two intake parts as a project and then I saw your thread.

I'm the opposite actually, coming from a flash tune and never using a piggyback. I had mhd stage 2 and xhp stage 3, never tracked it but did get an 11.64 at 120.3 on the strip. The only issue was that one of the camshaft bolts broke about 10,000kms after my warranty ended and I didn't get an extended one because I wanted to tune it. Was also getting fuel line fault codes, do decided to trade it in and get something with warranty. I've read alot about mission and seen things about ppl wanting big power going somewhere else cause Alex said he wouldn't push the car any further safely, which to me is a good thing. My concern is just something else failing, I bought this car as a demo with about 5000kms, so who's knows what happened before lol. I know this engine is stout, and the same goes for mission and their tunes, but it's still a bmw, and things can go break from time to time lol.

[cjpp78]

Originally Posted by G_B58

So the tranny lags a bit with the jb+?

shifts are a little slower when you're making more power due to hitting torque limits in software for trans. Actual flash tunes can raise or delete these torque limits. JB+ is just a boost controller so it cant do anything with that issue.

[cjpp78]

Originally Posted by G_B58

So if octane is added it fixes the shifts or at least improves them? Like adding e85 or running 94 oct?

I actually have one, been sitting at home for a few weeks now lol. Just been debating putting it on after reading the mission post, explaining how bmw tracks the cars performance to see if it's been tuned or a piggyback. I've got a dp, exhaust, and inlet, which give a nice improvement in throttle and power so im debating if it's really worth the risk of adding the jb+, especially if it will only make a small difference.

Adding octane will not improve transmission shifts..Making more torque with the extra boost causes the car to hit torque limits programmed into cars's software. This is why its shifts slower or softer than stock..

More octane will however Improve engine performance with jb+/jb4. My experience has been that the M340 runs much stronger while using jb+ if you have higher than 93 octane . The more you turn the jb+ up, the higher the octane requirements for good performance at that boost level. I run the jb+ turned all the way up but with a E30 mix in the tank and the car pulls much better than stock.
I can't say if its worth it to you or not but I think it will be an extra kick you will for sure notice. Fill up with 3.5 gallons of E85 with 10 gallons of 93 pump gas and crank the jb+ up if you decide to give it a try

[G_B58]

Alright well thanks, I appreciate the honest feedback.

Does the b58tu have a fueling cap? I think the gen 1 was around 400whp, which is why you had to use meth with the jb4 to get any further, if I recall correctly.

[GD1981]

Originally Posted by G_B58

Alright well thanks, I appreciate the honest feedback.

Does the b58tu have a fueling cap? I think the gen 1 was around 400whp, which is why you had to use meth with the jb4 to get any further, if I recall correctly.

The JB units have a fairly reliable track record in case you were wondering.
Secondly, with your existing mods, I’d go for a JB4 instead of a JB+, and be sure to get the EWG harness as well. Lastly, I’d run up to E25 on Map 3 and work yourself up as you get feedback from Burger on your logs. Right now, I’m running JB4 with no other mods and about E27 in the tank on Map 5 and the car pulls hard as hell. I have a few supporting mods awaiting shipment. AA catted DP and Dinan CAI.