[Dasky_spas]

What do the aux radiators do in the 8 series? Are they supplementary to the main radiator or for oil or dedicated to the charge coolers?

[Bulent Ali]

There are a few. After shutting down rather engine the fans work still circulating coolant an ( oil ) ? to the turbo chargers .
There are also radiators for oil cooling transmission cooling charge cooling . May find this info in technical data. I am sure mire experienced members here can correct me and give more details.

[Tenac]

Yea basically what Bulent Ali said is correct.

I forget the layout and total number. There are four separate cooling systems, one is the engine radiator, another is the charge cooler fluid, Oil rads, Transmission rads. When talking about turbo cool down the oil pump runs with a bypass engaged for turbo oil and the charge cooler pump and fans to keep cooling the turbo and engine down after shut off.

[Dasky_spas]

I was referring to the two aux radiators on the lower side inlets. Not sure their exact function.

[Tenac]

Originally Posted by Dasky_spas

I was referring to the two aux radiators on the lower side inlets. Not sure their exact funding.

Those are for the charge coolers.

[danibear]

In 850 option list, there is a “Cooling and High Performance Tire Package” which mentions an additional engine oil cooler.

I assume the above mentioned continues cooling down is something standard without this option?

Or I am wrong? I assume normal DD with occasional heavy gas push does not need this option?

Can 850 owners have this option tell some feedback? 1550 is not a high price, I am OK to add it just not sure if this fit my purpose, otherwise pointless to add more weight.

[Dasky_spas]

Originally Posted by danibear

In 850 option list, there is a “Cooling and High Performance Tire Package” which mentions an additional engine oil cooler.

I assume the above mentioned continues cooling down is something standard without this option?

Or I am wrong? I assume normal DD with occasional heavy gas push does not need this option?

Can 850 owners have this option tell some feedback? 1550 is not a high price, I am OK to add it just not sure if this fit my purpose, otherwise pointless to add more weight.

If you look up the radiator and upper/lower hoses, you'll also see 'Motorsports package' but most dealerships have no clue what it means. I've called a bunch.

The M8 and m850 have the same radiator and aux radiator so maybe there's a smaller version or piping. While the radiator is the same the piping for m8 is different so I doubt the inlets will work. However the best way to find out is to try!

I'm doing some experiments now on other parts and will report back.

[danibear]

Thanks!

[Dasky_spas]

https://autotecknic.com/products/cr-...-f90-m5-f9x-m8

These should fit the m850 so those of you with a tune, especially a Stage 2, this is probably advisable if you push the car repeatedly.

I'm adding a push fan to the main radiator using this company:
https://deltapag.com/products/18-bru...32780849479742

The push fan will help on slow downs such as turns, breaking, or in dd during traffic.

[JCtx]

I live in hot TX, where it's routinely above 100F for months, so I'll absolutely get that 'cooling' package, whatever it is. But I think the 2 lower side ones are for the turbo intercoolers.

[Dasky_spas]

Ya, they're the radiators for the charge cooler fluid. Just get the 90c thermostat and put the extra fan on or upgrade to the cf main radiator for faster cool downs.