[3.0L]

I just received a nice catalog for aftermarket BMW performance parts. One enhancement caught my eye, and that is a so-called plug and play module that can be setup to increase turbo boost.

So my question is, how does this unit accomplish increasing boost? I assume that our turbos have traditional waste-gates, so my guess is that this unit controls the waste-gate more aggressively.

Since that manufacturer claims more boost, this seems to imply that the waste-gate on our stock turbo setup never completely closes. Apparently, there something left to give from the turbo.

Do I understand this correctly? I'm not planning to modify my car, but I am curious how our turbos work. I have a pretty good understanding of turbo systems on aircraft and have more or less assumed automotive turbos are about the same, at least in regards to waste-gates.

[Killramos]

Are you talking about a dinan tune?

[Diver]

There have been products like this before, but most of them don't work because the ECU is smart enough to know what is going on.

[3.0L]

Originally Posted by Killramos

Are you talking about a dinan tune?

No. The device is called "Juice Box" from Burger Motorsports, as presented in the Bavarian auto sport catalog. They claim gains of 30 to 100 HP. The device can be programmed via a USB cable from a computer.

Beyond that, the box can be expensive, ranging from $280.00 to $530.00. Manufacturer claims unit can make "huge" turbo boosts.

Seems too good to be true. But as I mentioned, I have no plans to mod my car. It runs great and has plenty of power as it is.

[mrcheezle19]

troll?

[3.0L]

Originally Posted by mrcheezle19

troll?

Who, exactly?

[ska///235i]

Hahahaha

Juice box = JB#

[Cyberdemon]

http://www.burgertuning.com/N55_Stage2_Jb4.html

The JB4 is what is called a Piggyback tuner. It intercepts signals between the ECU and the engine and modifies them based on parameters stored within the box (Maps).

This allows the box to control the engine, including to your original question - the Electronic wastegate used on the turbo engines.

This allows it to increase the boost, modify the fuel map, and make other changes to get more power. This is similar to what the BMW MPPK (Performance Kit) which provides additional power on other BMW models, except BMW modifies the actual ECU rather than adding this in between module.

The benefit of a piggyback is it is easily removed if you are bringing the car in for service. A custom ECU not so much, which is why the BMW approved solution (for the 3 Series, but not 2 series) is preferable for some people who would rather have a less powerful option but keep the OEM support.

The risks of course with a piggyback are that if something does go wrong, you may be up the creek without a paddle. But many users run JB tunes with no problems.

[3.0L]

Originally Posted by Cyberdemon

http://www.burgertuning.com/N55_Stage2_Jb4.html

The JB4 is what is called a Piggyback tuner. It intercepts signals between the ECU and the engine and modifies them based on parameters stored within the box (Maps).

This allows the box to control the engine, including to your original question - the Electronic wastegate used on the turbo engines.

This allows it to increase the boost, modify the fuel map, and make other changes to get more power. This is similar to what the BMW MPPK (Performance Kit) which provides additional power on other BMW models, except BMW modifies the actual ECU rather than adding this in between module.

The benefit of a piggyback is it is easily removed if you are bringing the car in for service. A custom ECU not so much, which is why the BMW approved solution (for the 3 Series, but not 2 series) is preferable for some people who would rather have a less powerful option but keep the OEM support.

The risks of course with a piggyback are that if something does go wrong, you may be up the creek without a paddle. But many users run JB tunes with no problems.

Thanks for the informative response.

[mjposner]

More boost = more strain on engine, and if there is a failure, and they see the tune they will likely blame the tune and deny the warranty claim. That is why Dinan is so much more money, they back the warranty.

[hoppy6698]

Originally Posted by mjposner

More boost = more strain on engine, and if there is a failure, and they see the tune they will likely blame the tune and deny the warranty claim. That is why Dinan is so much more money, they back the warranty.

Well, technically Dinan doesn't 'back the BMW warranty,' they match the typical BMW time with their own warranty should something related to their components be pointed at as the cause of failure.

[alz0rz]

If you really are not a troll then there is a lot to be learned from the other 26 threads that have 'JB4' in their title in this part of the forum!

My personal experience with the JB4 has been very positive - click the link in my sig for the thread I created.

[3.0L]

Originally Posted by alz0rz

If you really are not a troll then there is a lot to be learned from the other 26 threads that have 'JB4' in their title in this part of the forum!

My personal experience with the JB4 has been very positive - click the link in my sig for the thread I created.

No need to get wrapped around the axle about it. This is the first time I've ever heard of "JB4."

[3.0L]

Originally Posted by Cyberdemon

http://www.burgertuning.com/N55_Stage2_Jb4.html

The JB4 is what is called a Piggyback tuner. It intercepts signals between the ECU and the engine and modifies them based on parameters stored within the box (Maps).

This allows the box to control the engine, including to your original question - the Electronic wastegate used on the turbo engines.

This allows it to increase the boost, modify the fuel map, and make other changes to get more power. This is similar to what the BMW MPPK (Performance Kit) which provides additional power on other BMW models, except BMW modifies the actual ECU rather than adding this in between module.

The benefit of a piggyback is it is easily removed if you are bringing the car in for service. A custom ECU not so much, which is why the BMW approved solution (for the 3 Series, but not 2 series) is preferable for some people who would rather have a less powerful option but keep the OEM support.

The risks of course with a piggyback are that if something does go wrong, you may be up the creek without a paddle. But many users run JB tunes with no problems.

Thinking about this a bit more, it seems apparent that in stock form, the waste-gates in our turbos never fully close, thus giving the stock electronic control enough latitude to keep the boost within or right at the factory boost limits, but no more. So the aftermarket device are leveraging the extra waste-gate movement towards fully closed to increase boost levels beyond stock. Do I have that correct?

My M235i is my first-ever turbo car and I must say that I'm extremely pleased with the stock performance. My only experience (and limited knowledge) is with turbocharged aircraft engines. Until recently, pilots often had to observe the manifold pressure gauge (equivalent to an automotive boost gauge, except reads in inches of mercury) so as to not over boost the engine, a condition that could be catastrophic. Also, as the aircraft climbs into thinner air, the pilot had to gradually increase throttle settings to retain the desired boost.

As with cars, more recent electronically controlled systems make everything automatic, with much less chance of damaging the engine.

Interesting stuff!

[Cyberdemon]

Originally Posted by 3.0L

Thinking about this a bit more, it seems apparent that in stock form, the waste-gates in our turbos never fully close, thus giving the stock electronic control enough latitude to keep the boost within or right at the factory boost limits, but no more. So the aftermarket device are leveraging the extra waste-gate movement towards fully closed to increase boost levels beyond stock. Do I have that correct?

No, the waste gate remains closed when boost is building, otherwise you'd effectively have a vacuum leak and would never reach peak boost. Once it reaches the factory limit, it will open as progressively needed to regulate the boost.

The aftermarket tune will keep the waste gate closed for longer, increasing the maximum boost. The factory BMW boost is kept at a conservative level to account for long term reliability, wide temperature and environmental conditions, etc - but knowing that there are lots of conditions and sensors which can be compensated by the computer, aftermarket tuners will crank that limit up within what they feel is reasonable via their tuning.

Engineers are purposely conservative, especially for a performance car which is likely to see very hard usage. Increasing the boost ultimately is going to amount to some additional heat/wear, etc, but most of the time that is within an acceptable limit, especially for people who are not operating at the extremes of the environment (IE a 24 hour race in Arizona).

[3.0L]

Originally Posted by Cyberdemon

No, the waste gate remains closed when boost is building, otherwise you'd effectively have a vacuum leak and would never reach peak boost. Once it reaches the factory limit, it will open as progressively needed to regulate the boost.

The aftermarket tune will keep the waste gate closed for longer, increasing the maximum boost. The factory BMW boost is kept at a conservative level to account for long term reliability, wide temperature and environmental conditions, etc - but knowing that there are lots of conditions and sensors which can be compensated by the computer, aftermarket tuners will crank that limit up within what they feel is reasonable via their tuning.

Engineers are purposely conservative, especially for a performance car which is likely to see very hard usage. Increasing the boost ultimately is going to amount to some additional heat/wear, etc, but most of the time that is within an acceptable limit, especially for people who are not operating at the extremes of the environment (IE a 24 hour race in Arizona).

Ok, that makes sense. It's different with aircraft engines, so you could see where I got off track. Aircraft engines "sneek up" on the boost as power is gradually applied. The waste-gate doesn't fully close until the aircraft reaches very high altitudes.

And again, thanks for the good information. I enjoy learning new stuff!