[The Silver Slammer]

Someone with experience looking at these logs please take a gander. Target boost 2-3 psi higher than I'm able to achieve.
https://datazap.me/u/wellstileandsto...g=1&data=3-12#

[The Silver Slammer]

Anybody?

[BOOSTLEE]

Originally Posted by The Silver Slammer

Anybody?

looks normal for a stock turbo.
try logging in one gear only, 3rd or 4th. each time you shift, diverter valve dumps all the psi then you have to build boost again on next gear.

[The Silver Slammer]

I would expect it to be closer, it was when I had the JB4 hooked up to it but I know JB4 does boost fooling. I'm running only MHD right now, that's what this log was from.

[Johnny Boost]

Originally Posted by The Silver Slammer

I would expect it to be closer, it was when I had the JB4 hooked up to it but I know JB4 does boost fooling. I'm running only MHD right now, that's what this log was from.

As the previous poster said, you're not logging properly. Start in third gear, not first, and do a pull from about 3k RPMs to red line.

[The Silver Slammer]

Originally Posted by Johnny Boost

As the previous poster said, you're not logging properly. Start in third gear, not first, and do a pull from about 3k RPMs to red line.

1. He did not say I was logging improperly, he simply made a recommendation to do a 3rd gear only pull.
2. If you want 3rd gear only you can zoom in and take a snap shot of the 3rd gear pull alone and see the delta between the target and the actual boost.

If you zoom in you can clearly see the car never reaches target boost, ever. Right after the hitting 3rd gear it climb slightly but falls as RPMs climb while target boost either climbs or plains out. At one time it appears to be even 3+ psi below target. In fact at 5031rpm its 4psi exactly low. I don't believe thats normal even for a stock turbo.

Just looking for some insight as to why this is the case. I have everything in my sig installed with exception of the JB4 which I've taken out for the time. I've also installed the GFB DV+.

[Pladi]

Originally Posted by The Silver Slammer

1. He did not say I was logging improperly, he simply made a recommendation to do a 3rd gear only pull.
2. If you want 3rd gear only you can zoom in and take a snap shot of the 3rd gear pull alone and see the delta between the target and the actual boost.

If you zoom in you can clearly see the car never reaches target boost, ever. Right after the hitting 3rd gear it climb slightly but falls as RPMs climb while target boost either climbs or plains out. At one time it appears to be even 3+ psi below target. In fact at 5031rpm its 4psi exactly low. I don't believe thats normal even for a stock turbo.

Just looking for some insight as to why this is the case. I have everything in my sig installed with exception of the JB4 which I've taken out for the time. I've also installed the GFB DV+.

1 . Calm the F down

[Torgus]

Not meeting target can be a number of things. Worn wastegates, boost leak, leaking DVs, the list goes on.

[BB 335i]

you can take a look at my gap in peak psi right now. you will feel much better about your then. lol

[philgli]

which intercooler do you run? I had the ARM 5" stepped with stock connections. I swapped for silicone connections and heavy duty clamps and literally picked up a full PSI in doing so...

[The Silver Slammer]

Turns out it's fairly normal to have boost tapering down to 11-13 psi range at the upper range of rpms on these N55s. Custom tune gets you a little more, E85 gets you a little more, PI gets you a little more and all the airflow things we do to these gets you a little less, but more CFMs (cubic feet per minute) so more power in the end. Funny how everyone equates boost to power no matter what. It's all about volume of air guys. Without getting too nerdy, basically we remove the kinks, tight bends, inlet and outlet restrictions and increase airflow in and out of the engine we can actually see boost stay the same or even drop a bit, but still make more power due to volume of airflow. the kinks, bends and restrictions are the resistance that it takes to make more psi. Like a 1" diameter hose flowing 50 gallons per minute or a 2" hose flowing 50 gallons per minute same volume but lower psi. but the bigger hose has the capacity to flow much, much more.

(This is all setting tuning/fueling aside)

Hopefully this makes sense.

[The Silver Slammer]

Originally Posted by philgli

which intercooler do you run? I had the ARM 5" stepped with stock connections. I swapped for silicone connections and heavy duty clamps and literally picked up a full PSI in doing so...

VRSF 7"

[philgli]

Originally Posted by The Silver Slammer

Turns out it's fairly normal to have boost tapering down to 11-13 psi range at the upper range of rpms on these N55s. Custom tune gets you a little more, E85 gets you a little more, PI gets you a little more and all the airflow things we do to these gets you a little less, but more CFMs (cubic feet per minute) so more power in the end. Funny how everyone equates boost to power no matter what. It's all about volume of air guys. Without getting too nerdy, basically we remove the kinks, tight bends, inlet and outlet restrictions and increase airflow in and out of the engine we can actually see boost stay the same or even drop a bit, but still make more power due to volume of airflow. the kinks, bends and restrictions are the resistance that it takes to make more psi. Like a 1" diameter hose flowing 50 gallons per minute or a 2" hose flowing 50 gallons per minute same volume but lower psi. but the bigger hose has the capacity to flow much, much more.

(This is all setting tuning/fueling aside)

Hopefully this makes sense.

Also since i noticed you are on MHD, i believe it was said they they don't go by boost target with MHD, they go by load. The boost target is more like a "ceiling" that they dont want boost to go above. So boost will always be some amount under boost target UNLESS you are overboosting for some reason.

Boost is a measure of pressure and not airflow, to your point. One goal to make power is to up the boost, another is to remove all airflow inefficiencies. Or, you can do both...

[The Silver Slammer]

What part of Georgia you in Phil?

[philgli]

Originally Posted by The Silver Slammer

What part of Georgia you in Phil?

Roswell/Marietta/Alpharetta

you?

[The Silver Slammer]

Evans/Augusta

[philgli]

Originally Posted by The Silver Slammer

Evans/Augusta

Oh that’s far

#missedconnections

[The Silver Slammer]

So I've got the last hard part left to install to make sure I am completely sure I don't have a boost leak and to try and maximize the stock turbo...the turbo to intercooler charge pipe! Besides messing with the wastegate or boost solenoid, the logs don't look like either of those could be an issue. But I hear this high pitched squeal when the car comes under load and starts making boost. This is the last place I haven't thoroughly gone through to check for cracks, leaks, etc.

Just showed up yesterday from Top Gear Solutions (VRSF). Here's a link for anyone who needs it.

https://topgearsolutions.com/vrsf-n5...free-shipping/

However it doesn't come with a new O-ring. Anyone have a part # on a replacement? If I'm gonna do it I wanna replace the O-ring while I'm at it.

Got the N20 TMAP Sensor on the way too so I can target a higher PSI with MHD and hopefully make more power and get a better 1/4 mile time!

[brakthru]

I didn't want to start a new thread but my situation is the dme keeps lowering the boost target. One log from Oct you'll see boost and target psi looking good. Should be 21-22psi. On the same map, the Jan log shows the dme lowered target down to 17psi so my boost hits around 19psi. I've started noticing this as the weather got colder. It seems the less traction I have the more the dme adjust timing or boost. I've experimented with this. I've run the map on a 60°f day and again on 35°-50°. The car would have a more difficult time keep tires on the pavement 3rd gear and up and reduce timing or boost. Dsc always off.

I know this is odd. I've tried different maps and reset adaptions. No change. The car limits power based on traction. At least that what I think or the dme could be faulty. Im waiting to hear back from my tuner. My 3.5tmap gave me some issues months ago but my tuner wrote the voltage in the map which fixed the startup issues.

Anyone have any idea why this is happening or experienced this? I'm running hybrid turbos and I dont see a boost leak. I'll need to check the charge pipe though. Not sure if that would affect target data though. Could it be the map? Dont seem likely to me.

Any help or leads appreciated.

https://datazap.me/u/brakthru1/log-1...og=0&data=3-23

[Torgus]

Originally Posted by brakthru

I didn't want to start a new thread but my situation is the dme keeps lowering the boost target. One log from Oct you'll see boost and target psi looking good. Should be 21-22psi. On the same map, the Jan log shows the dme lowered target down to 17psi so my boost hits around 19psi. I've started noticing this as the weather got colder. It seems the less traction I have the more the dme adjust timing or boost. I've experimented with this. I've run the map on a 60°f day and again on 35°-50°. The car would have a more difficult time keep tires on the pavement 3rd gear and up and reduce timing or boost. Dsc always off.

I know this is odd. I've tried different maps and reset adaptions. No change. The car limits power based on traction. At least that what I think or the dme could be faulty. Im waiting to hear back from my tuner. My 3.5tmap gave me some issues months ago but my tuner wrote the voltage in the map which fixed the startup issues.

Anyone have any idea why this is happening or experienced this? I'm running hybrid turbos and I dont see a boost leak. I'll need to check the charge pipe though. Not sure if that would affect target data though. Could it be the map? Dont seem likely to me.

Any help or leads appreciated.

https://datazap.me/u/brakthru1/log-1...og=0&data=3-23

Who is your tuna?

[brakthru]

Originally Posted by Torgus

Who is your tuna?

BQ.
You think its tuning vs hardware?

[Torgus]

Nah