E89 Z4 Track-ready Sleeper Build
- Thread starter Asbjorn
- Start date
Took a picture of my most recent trophies to celebrate the end of 2020. Really appreciate how reliable the car has been this year. Thanks to @Tony@VTT @Chris@VargasTurboTech and in particular @carabuser for all of the support this year. Happy new years!
Wow!
Congratulations! I am impressed with how you have taken this car to these heights. It is reliable, you know what works and doesn't and you also share plenty of knowledge.
Love it!
Hey Mate,
I love your Setup and read the thread in the past a few times. I am in the process of adding oil coolers to my car as I am overheating quite fast on the Nordschleife now as I got faster.
I am also planning for additional water cooling and hoping you could help me to understand how you connected the additional aux radiator.
I see where and how you connected the T piece for hot water to water cooler intake. But how and where did you connect the water hose with the cooled water?
The hoses from both aux coolers combine with the main radiator outlet behind and below the FMIC in the area marked with a red square below. We re-routed the hose from the main radiator to come out at the front front and go down below the FMIC inlet.
The 1-to-3 adapters were custom-made together with the hoses.
Both aux coolers were also custom-made according to my specs (tube design, fin-density, thickness, dimensions, position of inlets, ID of inlets, brackets etc) I made the drawings myself, and sent them to a local producer of radiators.
It is really easy to get stuff made to spec here in China, and it basically doesn't cost anything if you are willing to invest the time. I was also very fortunate that spoolstreet members helped me decide on what hose IDs to run and what not.
Last year I tried to offer these components as a ppk v2 kit with very little profit margin to give back to the community. However I did not get any orders. People were mostly interested in the red adapters. You can see one of them above below to the thermostat housing. Then VTT decided to make their own shortly after. It did not look as nice, but they were able to get the cost down quite a bit. They then "forgot" to also include a ppk option, most likely because they saw there is no demand. And they were probably right. Most people prefer to spend premiums on CSF radiators that barely make any difference at all.
Its pretty ridiculous.
I think the attraction for the csf is that it’s aluminium and although may not cool any better (debatable) it should last much longer than the plastic item
Nah. I think people blindly ran to CSF in hopes of better cooling performance.
@Asbjorn i am looking now for an additional aux radiator i will place before the main one, like you did with the DCT cooler.
I will install two oil cooler on the driver side soon and use the passenger one for the DCT with original m3 hoses i bought.
Running out of space for additional water cooling
@Asbjorn i am looking now for an additional aux radiator i will place before the main one, like you did with the DCT cooler.
I will install two oil cooler on the driver side soon and use the passenger one for the DCT with original m3 hoses i bought.
Running out of space for additional water cooling
Please do not do this. I had a large aux radiator in front of the AC condenser previously and even tested it in two configurations - parallel and serial - none of these configurations were any good and I ended up pulling it out again. All it does is slow down the speed of temperature change because there is more water in the system.Nah. I think people blindly ran to CSF in hopes of better cooling performance.
@Asbjorn i am looking now for an additional aux radiator i will place before the main one, like you did with the DCT cooler.
I will install two oil cooler on the driver side soon and use the passenger one for the DCT with original m3 hoses i bought.
Running out of space for additional water cooling
The problem with putting an aux radiator in front of the main radiator is that it does not increase the total effective cooler area available to your engine. It just increases the effective radiator thickness. It is much better to increase the frontal area of the coolers. Also you might experience that your AC stops working. The AC condenser operates at a much lower temperature than a radiator, and needs cool air to work. I had this problem even on the street if I ran MHD sport mode. Engine was running nice and cool, but I was not haha...
I think the reason OEMs put DCT coolers in front of radiators is that it normally runs at a lower temperature than both the engine coolant and the engine oil. It is also typically a thinner cooler. Of course putting it on the side is better. However the problem with this idea is that you desperately need this space for engine cooling instead.
Please look at what they did with the new M4 S58. It has engine coolant radiators on both sides in combination with a full height radiator in the middle. This means they actually increased the area available for engine cooling compared to the S55. The S55 only used one of the side aux coolers for engine cooling (the other was used for the intercooler). This should give you some idea of what direction you need to go in. Also remember that our dct main radiator is far from full length to begin with. There is the FMIC plus the dct cores both limiting the effective height available for engine cooling. I haven't done the measurements on the S58, but I would not be surprised if the new M4 has double the total radiator frontal area compared to a DCT N54. And for track applications in hot weather, the dct N54 radiator is probably only able to handle 200-250hp or so (it overheats even with just the stock 300hp)... and I guess it makes sense that double the area is needed for a 500hp car.
Also note that they don't put anything behind the engine oil cooler, because it is by far the hottest cooler of them all. Same is true for the old S65, where they have ducting behind the oil cooler.
Some more pictures of what I and others did for inspiration below. Below are the three radiators I managed to fit in. And I still get +110C coolant temps on track.
I have two engine oil coolers on the side here sitting in a V-config. Maybe you could make a similar setup but using the lower one for DCT cooling. However it will offer a bit less cooling compared to the oem setup.
Heres another picture of the side aux cooler. The pump next to it is the DCT oil pump.
By moving to a non-stepped FMIC, I was able to place an additional aux cooler behind it and below the main radiator. Another thing you could do is change the main radiator to a non-DCT version and then use an aux core like the one below for DCT cooling instead.
One of the local M4s did this setup for differential cooling. You may be able to do something similar for the DCT.
Thank you!
My plan indeed is to make a dual oil cooler V shape on the driver side for the engine.
Yesterday I scrapped the idea of a dct cooler on the passenger side and found that Hydra transformed the passenger side oil cooler to an additional aux radiator. Just like on the PPK except that one is on the driver side.
Next step is to measure the space I have to later introduce a bigger aux radiator on the passenger side.
That M4 Cooler there is an AMAZING idea! Need to check if I can fit anywhere under my car another cooler.
Diff cooler is also on my list but without priority right now.
Sombody was creative with placing an additional cooler:
I could fit one there also and try to get air there with air inlets like below M235CS
I will also look into modifying my bumper with extra air inlets as on the M235 CS
My plan indeed is to make a dual oil cooler V shape on the driver side for the engine.
Yesterday I scrapped the idea of a dct cooler on the passenger side and found that Hydra transformed the passenger side oil cooler to an additional aux radiator. Just like on the PPK except that one is on the driver side.
Next step is to measure the space I have to later introduce a bigger aux radiator on the passenger side.
That M4 Cooler there is an AMAZING idea! Need to check if I can fit anywhere under my car another cooler.
Diff cooler is also on my list but without priority right now.
Sombody was creative with placing an additional cooler:
I could fit one there also and try to get air there with air inlets like below M235CS
I will also look into modifying my bumper with extra air inlets as on the M235 CS
That's an m2cs racing not an m235cs. Also those holes on the bumper feed the brake duct, if you mimic a design for an oil cooler it won't work well unless the oil cooler actually has to behind it for to air flow through easily. If it's sitting on top of a shroud the air will back up preventing good flow.
Dang how much power is he running for the diff to require cooling? Must be deep in the 500 range or on some crazy wide slicks to stress out the diff that much.
Yeah it was a M4 GT4 race car. They only run slicks of course. I think it is mainly needed for endurance or in this case because it is so hot and humid in south china.
You are right. I was thinking of the predecessor M235 Racing or however it is called.
I know that those are meant for break ducts but actually i can 3d print whatever design i need. Thus i could route more air to places where i would need a little bit more air.
It was also my concern that the cooler is sitting on topf of the shroud and that i would need to create a path for air flow. Some brainwork but still an option on my list even if not one of the better ones.
I found the M4 aux side radiator now on ebay for quite small money. I will test my car with the passenger oil cooler as an aux radiator with two oil coolers on the driver side next on the nordschleife so log improvements. I guess the M4 Aux radiator will come sooner or later.
What do you have as a DCT cooler right now?
Was this originally a 6AT?
If it was a 6AT they make adapter fiting for the trans cooling lines so you can make your own AN lines and run a dual pass cooler on the front driver side and bypass the stock cooler and reroute the coolant lines. I'm assuming you have replaced the stock trans cooler.
Was this originally a 6AT?
If it was a 6AT they make adapter fiting for the trans cooling lines so you can make your own AN lines and run a dual pass cooler on the front driver side and bypass the stock cooler and reroute the coolant lines. I'm assuming you have replaced the stock trans cooler.
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Would you tell me the dimensions of your aux radiator in the picture?
I did some lookup and found that BMW actually sells nice side aux radiators on 535D , M2 and some other cars.
I can get them pretty cheap but i couldn´t find dimensions yet.
