JB4 for Gen3 VAG Group - Page 25 - N54Tech.com

George @ BMS · 11-25-2019, 06:32 AM

Quote:

Originally Posted by jb4998

Thank you for the reply... I was wondering, can you use AFR to track a boost leak? The reason I ask, I notice after I fully let off the throttle after any decent turbo engagement the boost is hanging between 0.1-0.4, and this in turn is causing the AFR to stay low, around 3.x-4 until I get on the throttle again.

Is the 0.1-0.4 boost reading indicative of a boost leak? Is coasting around in gear at 3-4 AFR going to cause a rich condition?

I would send you the logs, but I have already sent you two emails in the last 24 hours, and I don't want to be that guy

See reply on your other post.

blackgti · 11-26-2019, 02:27 PM

This may have been asked already but I cannot seem to find the answer. Is Map 3 the same as Map 2 except the peak boost is 6 vs 5? I’m running 93 with a ** and IC if it matters.

George @ BMS · 11-26-2019, 03:12 PM

Quote:

Originally Posted by blackgti

This may have been asked already but I cannot seem to find the answer. Is Map 3 the same as Map 2 except the peak boost is 6 vs 5? I’m running 93 with a ** and IC if it matters.

Correct. Map 2 has slightly more torque. Map 3 is done in such a way that its good for DSG and manual on 93. Power delivery feels more linear.

blackgti · 11-26-2019, 06:06 PM

Quote:

Originally Posted by George @ BMS

Correct. Map 2 has slightly more torque. Map 3 is done in such a way that its good for DSG and manual on 93. Power delivery feels more linear.

Great thanks George. My car definitely feels better with Map 3 than Map 2 and even Map 6 now that it’s colder out.

7.5smurfrabbit · **latest firmware -** 12-02-2019, 10:29 AM

whats the latest firmware?

George @ BMS · 12-02-2019, 10:37 AM

Quote:

Originally Posted by 7.5smurfrabbit

whats the latest firmware?

Its always in post 1.

7.5smurfrabbit · 12-03-2019, 06:27 AM

thank you master george

Nora2004 · 12-04-2019, 10:18 AM

I may regret asking this, but here goes, fuel duty bias, I've noticed having this set to 100 across the board will result in an AFR of mid 13's, but when logging in map 0 the stock AFR target is 14.6! Is it best to leave it as is or is the stock 14.6 target better? I had noticed a good while ago when helping a friend setup his map 6 he had forgot to enter the duty bias figure so they were left at 0, looking at his logs everyone of them had the AFR's bang on 14.6, that got me thinking and lead me to this question?

Any thoughts on this before I go and blow my motor up? Lol

George @ BMS · 12-04-2019, 11:47 AM

Quote:

Originally Posted by Nora2004

I may regret asking this, but here goes, fuel duty bias, I've noticed having this set to 100 across the board will result in an AFR of mid 13's, but when logging in map 0 the stock AFR target is 14.6! Is it best to leave it as is or is the stock 14.6 target better? I had noticed a good while ago when helping a friend setup his map 6 he had forgot to enter the duty bias figure so they were left at 0, looking at his logs everyone of them had the AFR's bang on 14.6, that got me thinking and lead me to this question?

Any thoughts on this before I go and blow my motor up? Lol

All other piggy backs use stock targeting. Even though the logs might look ugly at higher boost levels it wont melt the engine. At a certain point though boost wise you get a timing benefit when running richer and allows for more boost add safely without the ECU having to intervene continuously with corrections so 100 is the recommended value. This is also why we only recommend map 1 for guys that dont want to connect the AFR wire which is what does this biasing.

Nora2004 · 12-04-2019, 12:05 PM

Quote:

Originally Posted by George @ BMS

All other piggy backs use stock targeting. Even though the logs might look ugly at higher boost levels it wont melt the engine. At a certain point though boost wise you get a timing benefit when running richer and allows for more boost add safely without the ECU having to intervene continuously with corrections so 100 is the recommended value. This is also why we only recommend map 1 for guys that dont want to connect the AFR wire which is what does this biasing.

This is interesting! So right now I've got my boost dialled in with max ignition advance the ECU can offer, I'm currently low to mid 13's AFR, I get the while richer running helping to cool down the combustion, which I guess will result in more power in certain situations! So I'm assuming I can set my duty bias to zero, target 14.6 and log to ensure my ignition advance doesn't **** itself and I'd be good to go? I'm also assuming I can change the bias values in 10's to richen or lean the mixture?

God I love this ****!

George @ BMS · 12-04-2019, 04:15 PM

Quote:

Originally Posted by Nora2004

This is interesting! So right now I've got my boost dialled in with max ignition advance the ECU can offer, I'm currently low to mid 13's AFR, I get the while richer running helping to cool down the combustion, which I guess will result in more power in certain situations! So I'm assuming I can set my duty bias to zero, target 14.6 and log to ensure my ignition advance doesn't **** itself and I'd be good to go? I'm also assuming I can change the bias values in 10's to richen or lean the mixture?

God I love this ****!

Something like that but over all the 100 settings in the fuel bias will give you best performance. Normally its not something we adjust unless the car is going super rich. At 14.6 you will trigger a EGT safety the ECU has and then it pours in fuel especially under high load driving.

tegxsi · 12-05-2019, 10:26 AM

I was tinkering with a JB4 for Gen3 EA888...
I was kind of concerned how the AFR are in low 14s at peak boost/torque then slowly tapers down. I also noticed that it wasn't running any ignition advance in these areas either.
I learned that these cars will add more fuel based on load and modeled EGT in ECU. The exhaust manifold that is built into the head is water cooled to help keep EGT down. The engine also gets up to temperature amazingly quick.

It's really a neat little engine. Runs even better with a splash of E85.

George @ BMS · 12-05-2019, 04:43 PM

Quote:

Originally Posted by tegxsi

I was tinkering with a JB4 for Gen3 EA888...
I was kind of concerned how the AFR are in low 14s at peak boost/torque then slowly tapers down. I also noticed that it wasn't running any ignition advance in these areas either.
I learned that these cars will add more fuel based on load and modeled EGT in ECU. The exhaust manifold that is built into the head is water cooled to help keep EGT down. The engine also gets up to temperature amazingly quick.

It's really a neat little engine. Runs even better with a splash of E85.

Nice, also posted in wrong section