Port Injection 2020

nahor

Specialist
Sep 15, 2017
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2010 BMW 135i Single Turbo
There is only one problem with pi and thats when running your car with traction control on, the ecu is trying to pull fuel out the the pi is still spraying.

With full traction off its not a problem when tuned right.

Try driving a car in the rain running pi and traction control on, its not pleasant.
Is your PI controller’s boost reference pre or post throttle body? This sounds like it could be an issue of the controller seeing more boost than the manifold is, due to throttle closure
 

martymil

Major General
Sep 6, 2017
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Boost reference is of the ecu, its the aic spraying fuel whilst ecu is trying to pull it out and basically afrs go extremely rich and the whole system goes beserk.

The traction control system does not take into account the extra fuel being sprayed by pi.

I'm running a double barrel now with no issues at all and will be converting pi to direct port meth for knock suppression only to eliminate using small blends of E
 

nahor

Specialist
Sep 15, 2017
54
35
0
Ride
2010 BMW 135i Single Turbo
Boost reference is of the ecu, its the aic spraying fuel whilst ecu is trying to pull it out and basically afrs go extremely rich and the whole system goes beserk.

The traction control system does not take into account the extra fuel being sprayed by pi.

I'm running a double barrel now with no issues at all and will be converting pi to direct port meth for knock suppression only to eliminate using small blends of E
Off the ECU as in the TMAP wire? If so, that would likely be your problem. The TMAP is pre throttle body, and will see higher pressures than the manifold will during partial throttle conditions.

The ECU deals with this through its own internal model of airflow across the throttle blade at different positions, I believe, but the AIC has no way of doing so. If you move your AIC’s boost reference to be off the manifold, that should solve the problem, as it’ll then be able to see the correct boost at all times
 

V8bait

Lieutenant
Nov 2, 2016
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Texas
Off the ECU as in the TMAP wire? If so, that would likely be your problem. The TMAP is pre throttle body, and will see higher pressures than the manifold will during partial throttle conditions.

The ECU deals with this through its own internal model of airflow across the throttle blade at different positions, I believe, but the AIC has no way of doing so. If you move your AIC’s boost reference to be off the manifold, that should solve the problem, as it’ll then be able to see the correct boost at all times

Been saying this for years. Chris D made me a nice harness for an AEM sensor, not sure if he's still making them but moving the boost ref to the manifold is really helpful, especially for 6mt cars.
 
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chrisdfv

Corporal
Aug 29, 2017
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E90 335i
Been saying this for years. Chris D made me a nice harness for an AEM sensor, not sure if he's still making them but moving the boost ref to the manifold is really helpful, especially for 6mt cars.

Yes. Huge difference with the boost ref post throttle.
 

Naldo12

Private
Nov 10, 2019
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BMW 535i
Hi who is the best tuner for jb4. I have so much problem whit the jb4 I'm going to try someone else and se if that's my problem
 

houtan

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Nov 2, 2017
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135i N55 DCT; PS2
Been saying this for years. Chris D made me a nice harness for an AEM sensor, not sure if he's still making them but moving the boost ref to the manifold is really helpful, especially for 6mt cars.

Would love to know more about this. What sensor would I buy? Do I just drill a hole in the stock manifold? Is Chris D on the forums?
 
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chrisdfv

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Aug 29, 2017
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Would love to know more about this. What sensor would I buy? Do I just drill a hole in the stock manifold? Is Chris D on the forums?

Depends on how you want to do it. I just tee into my bov or turbo boost reference hose off a barb I have tapped into my stock intake manifold.
I use a 3.5 bar AEM sensor, but you can use any you'd like. The sensor scaling is a bit different then stock so it will require you to rework you AIC fuel table a bit, but it's not too bad.

3 wires on my harness.
-Ground
-Output signal to connect to AIC
-Power source for sensor(I add a female bushing connector to plug into the dme connector and get switched 5V from the dme. Same pin the flex fuel module uses to get power). DME large black sub connector pin 25.
Sensor 1.jpg
Sensor 2.jpg
Sensor 3.jpg
 

V8bait

Lieutenant
Nov 2, 2016
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Would love to know more about this. What sensor would I buy? Do I just drill a hole in the stock manifold? Is Chris D on the forums?

@chrisdfv he actually just posted lol.

I have the BMP solid intake so it has threaded bungs for many things, I run the Hobbs there and a larger line for the BOV and the threaded sensor directly. You could tap the factory manifold or use an adapter, I believe it's 1/8" NPT so you could throw a 1/4" barb adapter on and plumb it that way too.

Edit- what he said
 

houtan

Lieutenant
Nov 2, 2017
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@chrisdfv , @V8bait ,

Thanks! My car seems to be ok from the tmap but if there are issues I will plan to do this. Very cool.

Chris, do you sell the harness?
 

NoGuru

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Jan 9, 2018
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So I need to get the Hobbs installed and I want to put it in the manifold but I would like to have a fitting I can JBweld in place in case I need to change out the Hobbs.
Or is there a better way to do it?
Does anyone know what fitting I would need?
 

The Convert

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Jun 4, 2017
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A new alloy manifold and any fitting you like
I just saw another post with one of the manifolds you’re talking about. They really are great looking. The only change I wish was made would be to either expand the round to oval transition to be much longer, or to just keep it oval all the way to the plenum. They do look like the nicest on the market for this platform though.
 

V8bait

Lieutenant
Nov 2, 2016
500
773
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Texas
I just saw another post with one of the manifolds you’re talking about. They really are great looking. The only change I wish was made would be to either expand the round to oval transition to be much longer, or to just keep it oval all the way to the plenum. They do look like the nicest on the market for this platform though.

The alloy manifolds look better but honestly why I picked one up was because of the integrated PI and meth bungs on the BMP unit. I really hate using spacers, more chances to leak, and I wanted the PI to be positioned properly into the port. All the extra bungs are great for sensors like the AEM, Hobbs, vacuum lines or whatever. Design wise even the OEM style does improve on the plastic some, there's no bump going to cyl 6 for starters. Heat concerns can be mitigated by a phenolic spacer though I don't really think it's necessary, and weight wise the OEM style is lighter than most of the forward facing, which was important to me because added weight is a PITA.
 

The Convert

Captain
Jun 4, 2017
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The alloy manifolds look better but honestly why I picked one up was because of the integrated PI and meth bungs on the BMP unit. I really hate using spacers, more chances to leak, and I wanted the PI to be positioned properly into the port. All the extra bungs are great for sensors like the AEM, Hobbs, vacuum lines or whatever. Design wise even the OEM style does improve on the plastic some, there's no bump going to cyl 6 for starters. Heat concerns can be mitigated by a phenolic spacer though I don't really think it's necessary, and weight wise the OEM style is lighter than most of the forward facing, which was important to me because added weight is a PITA.
Which did you go with?