N54 water to air intercooler street build

[MDORPHN]

"It could be beneficial to A2A also, but probably mostly stepped ones. There is a HUGE difference in intake between the kidneys and the IC opening from the fan. It's probably almost a must that an A2W exchanger be at the top of the rad/behind the kidneys (or, ideally, cover the entire front of the rad) for the fan to really act well on it. I'll try to test it on my A2A, but really not expecting at lot on it. There's probably an IAT action on the fan already, but I can't find it"

This makes sense to me. I was getting heat soak during 20-25 minute sessions on road racing circuits with my large, stepped intercooler because so much of it was tucked behind the bumper cover, out of the airflow. I've since replaced it with a much smaller unit that is entirely in direct airflow and the delta over ambient dropped from 80 degrees to about 60 degrees.

Neil

 

[RSL]

I saw your post in the other thread, that's nuts. Similar ambients? Any change in ECT or oil?

 

[RSL]

Never mind, didn't see that second paragraph in the email notice. Good deal.

 

[Jake@MHD]

The speed table is a bust. It, and almost every other table I can find for the fan, act on fan set points, which are determined prior to the conversion and can obviously always be calculated to 0%. The set points are the "in", the conversion is the "out", so this will very likely need a logic/condition adjustment to work with vehicle speed. Maybe @jyamona could take a peek whenever he's poking (peek/poke, old BASIC commands LOL) around and see if it's something relatively easy he'd consider knocking out. Something to always return x% fan set point at < x kph and ECT from 10-15C below target or warmer should make it feasible for the fan to run when slow/stopped, but still operate normally over that speed.

Just thinking through the simplest option here, how about a duty cycle adder per vehicle speed table? Simple 2D table that you could zero out at higher speeds, but add say 20-30% DC at low speed, and maybe even 40% when stopped.

A bit better solution would be a 3D adder table with axis for IAT and vehicle speed.

 

[bantam]

Just thinking through the simplest option here, how about a duty cycle adder per vehicle speed table? Simple 2D table that you could zero out at higher speeds, but add say 20-30% DC at low speed, and maybe even 40% when stopped.

A bit better solution would be a 3D adder table with axis for IAT and vehicle speed.

This would be awesome! and likely as good as I can imagine without a significant amount of work to integrate additional signals, etc.

With this logic available, you could get away with having maybe 3 variants depending on season so that you don’t prevent the car from ever warming up in winter.

Obviously please contact me if you need a beta tester. (IJEOS)

 

[Jake@MHD]

With this logic available, you could get away with having maybe 3 variants depending on season so that you don’t prevent the car from ever warming up in winter.

Getting more involved now, but could also have a min coolant temp to activate and use the adders.

 

[bantam]

Is it possible or has anyone used a bypass switch just to simply turn the fan on and off on demand in the car?

Crude but functional and would leave all other basic DME logic intact.

I am a bit electronically stupid, but as far as I can tell, this is not possible the “easy way” with a relay.

I measured the voltage at the fan wires, and they appear to just be dumb power wires which are always energized. The small gauge wire that goes to the fan appears to be a PWM signal that goes to a motor control in the fan that actually pulses the current to the fan motor.

So to make this work, you would need to have a way to intercept the fan signal and add duty cycle to it with a micro control like an Arduino or something.

 

[bantam]

Getting more involved now, but could also have a min coolant temp to activate and use the adders.

Another thought on the 3D table is that it should be looking for a delta T between IAT and ambient to trigger.

But basically anything would be more effective than what I have now

 

[Jake@MHD]

I measured the voltage at the fan wires, and they appear to just be dumb power wires which are always energized. The small gauge wire that goes to the fan appears to be a PWM signal that goes to a motor control in the fan that actually pulses the current to the fan motor.

Yes it has a +12V, GND, and a PWM signal. In order to manually control the fan, you could probably wire another +12V to a knob style potentiometer and use the output of that to the fan instead of the PWM wire. That would give you adjustable manual control. There's other options with a relay to switch between manual control and the PWM from DME.

 

[typedRew]

I'm just along for the ride here and hopeful that we can make this happen, thanks everyone for digging in.

I am a bit electronically stupid, but as far as I can tell, this is not possible the “easy way” with a relay.

I measured the voltage at the fan wires, and they appear to just be dumb power wires which are always energized. The small gauge wire that goes to the fan appears to be a PWM signal that goes to a motor control in the fan that actually pulses the current to the fan motor.

So to make this work, you would need to have a way to intercept the fan signal and add duty cycle to it with a micro control like an Arduino or something.

I halfway assumed thats how it would be, but i was hopeful there would be a simple hardware only solution.

 

[RSL]

Just thinking through the simplest option here, how about a duty cycle adder per vehicle speed table? Simple 2D table that you could zero out at higher speeds, but add say 20-30% DC at low speed, and maybe even 40% when stopped.

A bit better solution would be a 3D adder table with axis for IAT and vehicle speed.

Nothing wrong with easy and that would be perfect I think. There's a VS speed vs. set point % (0-100%) in there already. If it could be made a set point adder instead of a scale, might not even need to do much at all, just change it's read from * to + for set point calcs.

0-x mph to whatever set point % adder entered and last speed break (or anything over last break programmatically) to 0% to allow for stock SP calc/level (including 0%). 3D with IATs would be way better though. No one would complain if it took a little longer to have that

@jyamona kl_el_v

 

[bantam]

Getting more involved now, but could also have a min coolant temp to activate and use the adders.

Thinking about this further, this would be the easiest thing to implement manually if it complicates the logic, just add a temperature switch and a normally open relay to the fan power wires (or maybe just the signal wire)

 

[bantam]

So it seems like RSL has pretty much slain the low speed driving issue by locating an unused table which triggers the fan based on IAT with the help of Martial@MHD. Hopefully these tables can be uploaded to the public .XDF once they are vetted for the other ROMs.

By default the tables are empty, but seem to work once populated (drive cycle datalogs below

datazap.me | bantam | IAT fan, 7c trigger 2

datazap.me

Once again, this is pretty much all thanks to RSL figuring this stuff out, locating the tables in WINOLS is a bit over my head.

My upcoming tasks are:

1)leak detection, keep losing water from the system
2)Upgraded front mount heat exchanger
3)Test rig Ice chiller in trunk (will essentially be a 50ft coil of aluminum pipe in an ice-chest in the trunk) The purpose is to dyno and determine if the ice chiller is really worthwhile.
4) E60/flex fuel tune

 

[Jeffman]

Good work!
Can’t wait to have these tables posted publicly for IJEOS.

 

[bantam]

This feature has been tested on INAOS by RSL, and IJEOS by me. If RSL agrees, and you understand/accept the potential risk of testing a feature like this, I can share it with you.

 

[bantam]

Got the Dye into it....surprise surprise, the core is leaking into the charge pipe.... looks like I have been running water mist as well as water to air intercooler!

 

[aus335iguy]

Awesome work, and well done !

 

[Panzerfaust]

Oh man is it beautiful to see IATs stay at a steady 30° the entire time lol. I really hope it's as effective when you aren't running surprise WMI you dont happen to have any traditional pull logs with that setup yet do you? My apologies if I just missed it somewhere in the thread, and I understand if you wanna wait on that until you get a leak-free setup!

My worthless 2c is to go with an OEM replacement over a Chinese clone. Since you're testing something that so few people have done it's probably best to try to keep it bulletproof and like you said, I could see a Chinese knockoff being likely to leak. But that's also a bit of selfish of me because I want to see the 100% complete end result and it's not my money going towards the project, so take it FWIW I suppose!

 

[NoQuarter]

Unless the DME is doing current sensing on the power supply, there isn't enough wires/sensors to provide any feedback or error sensing, etc. as far as I can tell.

You have ground, power and a PWM. Max fan speed, during an induced error condition, is 90% PWM

 

[Panzerfaust]

Unless the DME is doing current sensing on the power supply, there isn't enough wires/sensors to provide any feedback or error sensing, etc. as far as I can tell.

You have ground, power and a PWM. Max fan speed, during an induced error condition, is 90% PWM

Like I said, I didnt read the instructions so I dont know if you splice the controller in or not but it sounded like it was full racecar style stand-alone, where you unplug the factory connections from the WP and plug in the module itself alone. So my reasoning behind thinking possible codes is that the DME might not see anything from the WP or fan and throw codes due to being "blind" other than the temp sensors. However I've never unplugged any of that and ran the car, and my questioning could likely be answered by just browsing the PDF instructions later.