Mishimoto radiator?

Rob09msport

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I wouldn't say that's a good thing as the thermostat controls the temps not the radiator, all the radiator does is cools water.

If your having temp swings I'll be looking into water pump or thermostat that's not working correctly.

What you should be looking for in a radiator is extremely stable coolant temps that don't fluctuate from the pre-set temp either in the tune or thermostat.
The n54 targets different temps for diff driving so it will run very hot cruising for better emissions and then when you turn up the wick it will drop temps so this is actually normal.

The manual version with a separate tranny cooler should not have this issue as the dme should be able to control the temp I would think. The auto obviously has a design flaw.
 

bantam

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Nov 20, 2017
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I have the 6at CSF radiator, but do not live in an area where I can really evaluate the cold weather performance.
Can someone articulate why the lack of separation is a design flaw and how that would affect engine operating temperature? The thermostat and water pump dictate the flow. So if the radiator is cooling too much, that is really a DME problem.

If the concern is heater core temperature...
If I am correct in assuming that the top radiator hose is the radiator outlet (and that's where the heater core taps in), you are facing a physics problem.

Your options would be to move the heater core supply location or block the kidney grilles for winter.
 
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The Convert

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The upper radiator hose is the return from the engine to the radiator. It feeds the heater core. I suppose the issue could be that the coolant returning to the engine is too “cold” and has more thermal capacity when in the engine and is extracting “too much” heat out of the engine. This would keep oil temps lower and overall engine temp down, making warmup take longer or never happen depending on ambient and post radiator coolant temps. Not sure how the t-stat and wp would play into it, but the t-stat can be opened by the DME. The idea of blocking off a portion of the radiator for winter is a really interesting idea though. Ford had to do that on the focus rd intercooler.

Good topic to discuss and consider though.
 

martymil

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The n54 targets different temps for diff driving so it will run very hot cruising for better emissions and then when you turn up the wick it will drop temps so this is actually normal.

The manual version with a separate tranny cooler should not have this issue as the dme should be able to control the temp I would think. The auto obviously has a design flaw.

I've helped tune and road test my mates single turbo kit and its an auto and it has no wild collant temp swings, its actually quite stable and thats with ambient temps of 100f+ but we did get rid of the water to oil heat exchanger for the trans and installed a modified aux rad to cool the trans oil so this might be the cause of his issues.

I brought a CSF rad for my 1m and still running the aux radiator and the temps virtually don't budge after it hits targeted temp, its one of the best investments I've made but I also changed my thermostat as it was over 7 years old to make sure my temps stay solid.
 

Rob09msport

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I've helped tune and road test my mates single turbo kit and its an auto and it has no wild collant temp swings, its actually quite stable and thats with ambient temps of 100f+ but we did get rid of the water to oil heat exchanger for the trans and installed a modified aux rad to cool the trans oil so this might be the cause of his issues.

I brought a CSF rad for my 1m and still running the aux radiator and the temps virtually don't budge after it hits targeted temp, its one of the best investments I've made but I also changed my thermostat as it was over 7 years old to make sure my temps stay solid.
Its only an issue for people in cold climates with the csf. Also if your friend logs temp on the highway I gaurantee it will be getting oil to 240 or higher if it's mild weather . Under harder driving the dme targets a performance orientated temp and if it's 100 out it also gets way more aggressive. The cooling thread going on right next to this one has all the info about kft and high modes with the temp logic explained.
 
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martymil

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The oil temp never exceeds 230c on the hwy even with low ambient temps of sub 90f, removing the trans heat exchanger
played a big role with that.

The trans is much happier too these days as it runs much cooler and seems to be happy running xhp with stock internals. (street driven only)
 

barry@3DM

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For those interested here are the two of them together. Not the greatest comparison pic but something none the less. I have dimension differences but I don;t have my notebook on me right now. Will edit and post up differences later.

Off the top of my head...

Mishimoto (top)
Core width: 23.5"
Core height: 15"
Core thickness: 1.50"
# of rows: 49
Individual tube outer thickness: .070"

CSF (Bottom)
Core width: 24"
Core height: 15"
Core Thickness: 1.66"
# of rows: 41
Individual tube outer thickness: .070"


20181128_161000.jpg
 
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martymil

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I believe the csf would be better in hotter climates as its not as dense as the mishimoto.

Having a thicker core.and spaced out water tubes allows more airflow.and wouldn't get jammed up with dirt and debris as easily.

I asked the local radiator builder which one he would choose and he said the csf for our hot climates here in oz.

All I can say we are heading for a very hot weekend here and a very hot summer.and it hasn't let me down yet, the temps are very stable

I only tested the csf and its been awesome
 

bantam

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Just an update for cold weather folks, the radiator is a real problem if you are trying to warm the car up. On a 38f day, I was driving the car for 20 minutes on the highway, the car would not warm up until I got stuck in traffic, at which point, the coolant heated to 200f and regulated normally.

In my line of thinking, there is likely a setting in the DME that could remedy this, but it will take a few more people documenting this issue. I have messaged MHD on facebook, and it would be nice if we could get it onto Jyamona's radar.

 

Jeffman

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Just an update for cold weather folks, the radiator is a real problem if you are trying to warm the car up. On a 38f day, I was driving the car for 20 minutes on the highway, the car would not warm up until I got stuck in traffic, at which point, the coolant heated to 200f and regulated normally.

In my line of thinking, there is likely a setting in the DME that could remedy this, but it will take a few more people documenting this issue. I have messaged MHD on facebook, and it would be nice if we could get it onto Jyamona's radar.

Have you played with the MHD options for cooling when flashing? Certainly for winter daily driving you’d keep it set to “stock” or “normal” (I forget what it’s called exactly). There are also the cooling tables in the latest XDF / TunerPro which you or your turner can adjust.
 

bantam

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Have you played with the MHD options for cooling when flashing? Certainly for winter daily driving you’d keep it set to “stock” or “normal” (I forget what it’s called exactly). There are also the cooling tables in the latest XDF / TunerPro which you or your turner can adjust.
My tune is set to normal cooling mode as far as I know. I looked at the tables available, and they really relate to when the various modes engage. What I think that I need is the next layer of depth to be unlocked, which would be like pump duty cycle and thermostat settings for warm up cycle.

My alternatives would be to put block offs in the kidney grilles or add a mechanical thermostat somewhere in the system, though neither are desirable. Luckily this is not a daily driver, so It is not critical, but still somewhat bothersome.
 

bantam

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I would replace the thermostat as it sounds like it maybe slightly stuck open

I just replaced it when I did the radiator, perhaps I will buy a BMW brand one this time.

My impression is that the thermostat is not a true mechanical thermostat and is being manipulated by the DME
 

martymil

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The thermostat is mechanical but has a heating element running through the center of it so if the dme wants it open earlier its just energizes it and heats the thermostat to make it open

The only way it would let water bypass the thermostat would me mechanical or electrical failure

Or its that cold and you need to block the radiator air flow with newspaper until it warms up