Charge air temps different bank 1 and 2

[Nillious]

I have always had a charge temp difference between banks. Is I have always had this. I have probably 30 logs of this same exact situation. Back 2 is ALWAYS hotter on a pull but they remain around the same in normal driving so I don't think it's a sensor. I have bled the intercoolers and there is no air. Like I've said I've seen this for years and just thought I'd ask if anything specific can cause this.

https://i.imgur.com/gEQDYQN.png

[Nillious]

https://imgur.com/a/AD0OL0j

Screwed the first link up and can't edit on mobile site.

[LowKeyLoki]

Pretty sure there is only one charge air temp sensor on the back side of the SC. Maybe it’s giving both banks as a calculation? There’s only the two manifold pressure sensor on each side so idk how it would tell the difference between air temps on each bank.

[Fresh.S4]

Pretty sure there is only one charge air temp sensor on the back side of the SC. Maybe it’s giving both banks as a calculation? There’s only the two manifold pressure sensor on each side so idk how it would tell the difference between air temps on each bank.

mine is the same with temps, one side is slightly warmer.

[STXA7]

I have always had a charge temp difference between banks. Is I have always had this. I have probably 30 logs of this same exact situation. Back 2 is ALWAYS hotter on a pull but they remain around the same in normal driving so I don't think it's a sensor. I have bled the intercoolers and there is no air. Like I've said I've seen this for years and just thought I'd ask if anything specific can cause this.

https://i.imgur.com/gEQDYQN.png

I have seen this question mentioned before on the other audi forum (inferior to audizine)
https://www.audiworld.com/forums/a7-192/200k-miles-3071084/

Check out the product description below
https://www.velocityap.com/product/divorced-supercharger-cooling-ports-audi-3-0-tfsi-b8-b8-5-s4-s5-c7-a6-a7-sq5-q5/?srsltid=AfmBOopDirIMqeJzYjWhDFcLAYmObGg9WJ4NKRoSl 6j_8XmWryRWd8VL

I personally have these ports installed and would be willing to provide my bank1 / bank2 temps if you could guide me on how to obtain the data . I only have 034 SPI app, not the VCDS .

The best theory is that due to the asymmetrical design of the coolant crossover pipes, there is more flow on one side than the other.

I have run standard 3/4" hoses of identical lengths for left and right sides of upper and lower intercooler ports.

I've read another theory that due to the fact that the intake path takes a bend , that the airflow within the blower itself is inherently imbalanced, though I don't think that's as much of a contributing factor.

It's a relatively cheap mod compared to all the others and at minimum would increase overall coolant flow even if bank 1 and 2 haven't attained equilibrium.

photo of setup
https://imgbb.com/ftzqBxM
https://imgbb.com/Rb4ymNW

Others have provided feedback that this setup would be perfected if I can switch the billet T fittings for Y fittings that have better flow characteristics. I've thought about it, and wonder if the increased pressure created by the T fitting would be beneficial to keep on either the inlet or outlet ports. Another feedback detail would be to run the outlet hose directly downward instead of upward as pictured in the above links. I'll get around to it eventually .

edit: while on the topic, I've also had phenolic spacer plates installed between the blower and engine. This was a part of the same goal to lengthen amount of time before heatsoak / reduce IAT / IAT recovery times. I have read on forums for other car brands / engines that all seem to share a common problem of having one specific cylinder overheat relative to the others, in some cases leading to catastrophic failure. To my understanding, our platform ECU would likely just pull power to either that cylinder, that bank, or entire engine so that we never suffer those grenading issues that others have had with older models from different auto brands. I could see this as being a possible contributing factor to the imbalance if the source is the engine and not the blower design.

[Fresh.S4]

I have seen this question mentioned before on the other audi forum (inferior to audizine)
https://www.audiworld.com/forums/a7-192/200k-miles-3071084/

Check out the product description below
https://www.velocityap.com/product/divorced-supercharger-cooling-ports-audi-3-0-tfsi-b8-b8-5-s4-s5-c7-a6-a7-sq5-q5/?srsltid=AfmBOopDirIMqeJzYjWhDFcLAYmObGg9WJ4NKRoSl 6j_8XmWryRWd8VL

I personally have these ports installed and would be willing to provide my bank1 / bank2 temps if you could guide me on how to obtain the data . I only have 034 SPI app, not the VCDS .

The best theory is that due to the asymmetrical design of the coolant crossover pipes, there is more flow on one side than the other.

I have run standard 3/4" hoses of identical lengths for left and right sides of upper and lower intercooler ports.

I've read another theory that due to the fact that the intake path takes a bend , that the airflow within the blower itself is inherently imbalanced, though I don't think that's as much of a contributing factor.

It's a relatively cheap mod compared to all the others and at minimum would increase overall coolant flow even if bank 1 and 2 haven't attained equilibrium.

photo of setup
https://imgbb.com/ftzqBxM
https://imgbb.com/Rb4ymNW

Others have provided feedback that this setup would be perfected if I can switch the billet T fittings for Y fittings that have better flow characteristics. I've thought about it, and wonder if the increased pressure created by the T fitting would be beneficial to keep on either the inlet or outlet ports. Another feedback detail would be to run the outlet hose directly downward instead of upward as pictured in the above links. I'll get around to it eventually .

edit: while on the topic, I've also had phenolic spacer plates installed between the blower and engine. This was a part of the same goal to lengthen amount of time before heatsoak / reduce IAT / IAT recovery times. I have read on forums for other car brands / engines that all seem to share a common problem of having one specific cylinder overheat relative to the others, in some cases leading to catastrophic failure. To my understanding, our platform ECU would likely just pull power to either that cylinder, that bank, or entire engine so that we never suffer those grenading issues that others have had with older models from different auto brands. I could see this as being a possible contributing factor to the imbalance if the source is the engine and not the blower design.

i have the Vap adapters as well. their is still a slight temp difference. ill have to check which bank on mine is the warm side.
i believe it is like you said regarding intake paths (at least thats what flow charts look like)
pressure is not a problem.

ps) your setup is crazy looking with those Ts. and how close they are to the pulley like that. def use Y adapters

[STXA7]

i have the Vap adapters as well. their is still a slight temp difference. ill have to check which bank on mine is the warm side.
i believe it is like you said regarding intake paths (at least thats what flow charts look like)
pressure is not a problem.

ps) your setup is crazy looking with those Ts. and how close they are to the pulley like that. def use Y adapters

*sad trombone sound effect* interesting that the ports don't remedy the situation. Do you know if the difference between two banks was reduced post-install of ports?

We do have the 1 side of the supercharger that has the front shaved smooth, while other side is fully cast with same texture as rest of the unit.
Has anyone ever machined the other side so that it can be symmetrical? I guess that would only make a difference if it's radiant heat dissipation deficiency caused by difference in metal mass.

The rubber hoses are so stiff that I'm not too worried about the potential of it flexing and rubbing the upper pulley. There's enough clearance IMO with the current OE 63mm upper which implies that a future 57mm should clear better.

Only other thing i can come up with is to center the CWA pump somewhere in the front crashbar instead of having it off under driver side headlight. If that doesn't 'fix' it, then the cause has to be like the other guy said sensor positioning / limitation that is fucking with the way ECU calculates bank 1 bank 2 temp value.

Is there any performance to be gained from 'solving' the imbalanced bank temp phenomena? Do the tunes pull power due to the imbalance ? If not it's just one of those things you can't unsee and will have to keep the OCD demons at bay lol

[Fresh.S4]

*sad trombone sound effect* interesting that the ports don't remedy the situation. Do you know if the difference between two banks was reduced post-install of ports?

We do have the 1 side of the supercharger that has the front shaved smooth, while other side is fully cast with same texture as rest of the unit.
Has anyone ever machined the other side so that it can be symmetrical? I guess that would only make a difference if it's radiant heat dissipation deficiency caused by difference in metal mass.

The rubber hoses are so stiff that I'm not too worried about the potential of it flexing and rubbing the upper pulley. There's enough clearance IMO with the current OE 63mm upper which implies that a future 57mm should clear better.

Only other thing i can come up with is to center the CWA pump somewhere in the front crashbar instead of having it off under driver side headlight. If that doesn't 'fix' it, then the cause has to be like the other guy said sensor positioning / limitation that is fucking with the way ECU calculates bank 1 bank 2 temp value.

Is there any performance to be gained from 'solving' the imbalanced bank temp phenomena? Do the tunes pull power due to the imbalance ? If not it's just one of those things you can't unsee and will have to keep the OCD demons at bay lol

i only recently (last year) discovered that you can measure each banks temp. so i only know of it with my current setup.
im running dual cwa50 pumps (oem location and the other mounted on the passenger side that feeds into the hx)

im not bothered by the temp difference and i kinda forgot about it until this post.
hopefully others can chime in.