Is JBD worth it?

DbLog · 03-28-2014, 08:20 PM

My concern with JBD is adding fuel but no air. My philosophy with diesels in the past is to add fuel and clean it (the smoke) up with more air. If the JBD is not adding air to burn the fuel where is the excess fuel going? Maybe there is enough air to burn it...maybe the dpf or cat. I don't know the answer to that question but it is a concern of mine. No doubt there are horsepower and torque gains but at what cost to the longevity of the emissions systems?

335dM · 03-28-2014, 08:42 PM

MAF controls it!

DbLog · 03-29-2014, 10:02 AM

Quote:

Originally Posted by 335dM

MAF controls it!

MAF controls what?

I assume the MAP sensor controls boost. As I understand it the JBD only increases rail pressure. Just trying to learn...

335dM · 03-29-2014, 10:16 AM

Quote:

Originally Posted by DbLog

Quote:

Originally Posted by 335dM

MAF controls it!

MAF controls what?

I assume the MAP sensor controls boost. As I understand it the JBD only increases rail pressure. Just trying to learn...

The mass air flow determines the amount of air coming into an fuel injected engine and passing that data to your car's ECU.

DbLog · 03-29-2014, 11:18 AM

Quote:

Originally Posted by 335dM

The mass air flow determines the amount of air coming into an fuel injected engine and passing that data to your car's ECU.

That air gets compressed by the turbos. The MAP reads the charged air in the manifold and adjusts turbo boost accordingly. Since the JBD doesn't increase turbo boost but only adds fuel, which the ecu doesn't account for, I'm concerned that there is an excess of unburnt fuel that may be deposited in our lovely emissions systems.

335dM · 03-29-2014, 01:32 PM

Quote:

Originally Posted by DbLog

Quote:

Originally Posted by 335dM

The mass air flow determines the amount of air coming into an fuel injected engine and passing that data to your car's ECU.

That air gets compressed by the turbos. The MAP reads the charged air in the manifold and adjusts turbo boost accordingly. Since the JBD doesn't increase turbo boost but only adds fuel, which the ecu doesn't account for, I'm concerned that there is an excess of unburnt fuel that may be deposited in our lovely emissions systems.

That is for sure!

32valves · 03-30-2014, 06:41 AM

I have had mine on since Christmas @ 80% and have had no problems.
Every now and then it will go in limp mode @ 100%.
And say something about low fuel rail pressure but I just clear it and keep it moving.

darkevo · 03-30-2014, 03:14 PM

Quote:

Originally Posted by geost

Are you guys running your JBD at 100%? I've had mine installed for about two weeks now at the stock "60%" but kinda scared to bump it up to 100% haha.

100% installed second day I got it, no errors.

03-28-2014, 08:20 PM	#23
DbLog Private First Class 14 Rep 106 Posts Drives: 2011 335d Join Date: Mar 2014 Location: Greater Detroit iTrader: (0)	My concern with JBD is adding fuel but no air. My philosophy with diesels in the past is to add fuel and clean it (the smoke) up with more air. If the JBD is not adding air to burn the fuel where is the excess fuel going? Maybe there is enough air to burn it...maybe the dpf or cat. I don't know the answer to that question but it is a concern of mine. No doubt there are horsepower and torque gains but at what cost to the longevity of the emissions systems?
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03-28-2014, 08:42 PM	#24
335dM Major 139 Rep 1,363 Posts Drives: 335d m package Join Date: May 2011 Location: montreal iTrader: (0)	MAF controls it!
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03-30-2014, 06:41 AM	#29
32valves Captain 114 Rep 934 Posts Drives: 2011 335d sport Join Date: Mar 2014 Location: DC area iTrader: (0)	Jbd I have had mine on since Christmas @ 80% and have had no problems. Every now and then it will go in limp mode @ 100%. And say something about low fuel rail pressure but I just clear it and keep it moving.
	Appreciate 0 Quote