Global Warming.
"In this Product Series, I document my experiences with the Clubsport Cooling Package for the M3 V8 made by DO88.
In this entry, I discuss why cooling upgrades become a priority. I then unbox all components of the kit sourced in Sweden, and take a deep dive into the technical merits of each."
- Matt
It was getting hot.
Cooling upgrades had not been on my radar for the Stripper for the last years. The local weather and absence of any meaningful track time meant temperatures never rose beyond the factory thresholds, sort of.
With the development of the SXX-EVO programs, engine and transmission cooling become a more critical variable. We're revving higher, and increasing the final drive ratios to shorten gearing. We are spending more time at higher revs and shifting more often.
Particularly on the S65-EVO, I am able to go in further into the engine management parameters of the MSS60, considering our efforts to luck the DME to allow 9,000 RPM shifts with the DCT.
The MSS60 used for the S65-EVO's testing has gone through over 100+ flashes as of today.
Temperature thresholds.
We have been exploring the myriad of rev limiters present on the MSS60 DME. There are many, and most importantly, some limiters are directly correlated to water, oil and DCT fluid temperatures.
If temperatures exceed certain thresholds, the DME will pull engine power dynamically before the redline. To clarify, the rev range at which it pulls ignition timing will vary per these limiters. All of this happens without any codes or limp modes present.
During various test drives, we were purposely revving the S65 out until the fuel cut off. We were able to observe, log and correlate these changes.
The need for cooling.
With the SXX-EVO Programs, our goal is to push the limits of stock displacement S65s. From our road and dyno tests, increasing cooling capacity and efficiency of the system was deemed a needed luxury.
My search for options was short. There are a few companies making cooling upgrades for the V8 M3, but only one has garnered universal praise for the usefulness of their kit: D088.
During the Summer of 2024, I source the complete Clubsport Racing kit for the M3 V8 DCT directly from DO88 in Sweden. All their products are made and assembled in-house. Below, I document the technical features of each component.
The kit includes the radiator, engine oil cooler, DCT fluid cooler and the power steering fluid cooler.
The power steering fluid was a later addition to my plans.
Radiator.
The original M3 V8 radiator is rather good: it's sized well and has a decent core. The intent of DO88 was to create a plug and play upgrade, as such they were restrained by the physical limitations of the original mounting locations.
Dedicated M3 V8 race cars usually opt for a V mounted radiator with massively increased core volume. It requires a complete redesign of the front carrier assembly. It's overkill for a dual purpose car.
In this case, the DO88 unit has a 14% increase in volume. Still, it's plenty for more M3 V8 owners's street and track use. Taking it straight from the brochure, DO88 claims an 8% reduction in water temperatures compared to OEM in testing conditions where all else stays equal.
The radiator is made with a 41mm dual aluminum core design.
The fin height is 6.3mm.
All fluid connecting points are machined to fit the original hoses.
The brackets to mount the radiator to the carrier assembly are all present.
Oil cooler.
The original BMW oil cooler for the S65 is rather small, constrained by its position on the lower section of the front bumper. If you've experienced oil temperatures beyond 3/4 on your gauge, the limited cooling capacity of the original unit may be the culprit.
DO88 engineered a kit that would fit the OEM mounting points, yet provide significant increases in cooling capacity by 69%.
They used a 10 row core with high density offset fins. Offset fins break up airflow hitting the cooler, creating aero turbulence and adding surface area that improve the radiator's heat transfer capacity.
The actual active cooling area increase is 59%.
The bigger cooler evidently increases oil volume by 13.9% in the cooler itself. A little bit more oil will need to be accounted during the initial oil top up.
The oil cooler is designed to fit OE mounting points. The brackets were specifically machined and welded at the required angles.
Additionally, the oil cooler comes with complementary o-rings, bolts and silicone caps.
Power Steering Fluid Cooler.
I have previously documented my woes with leaking power steering fluid in the entry "Of course it leaked". Boiling fluid has been a bigger problem on the V10 due to the heat it generates and my year long use of the car. The initial fix was to upgrade to the Performance Power Steering Reservoir.
While it fixed the leaking issues, it did little for managing fluid temperatures. The D088 power steering fluid cooler specifically solves this problem with an improved power steering fluid cooler unit for the V8.
It's a massive improvement over stock when reviewing the specs: the active cooling area and fluid capacity are doubled.
The fluid capacity increase is 100ml, equal to 200ml total fill. It's dimensionally bigger in height and depth over the original unit.
The fittings are designed specifically for the M3 V8.
It is the unique component of the kit that is finished in black.
DCT Cooler.
I kept the best for last - the Clubsport DCT cooler kit from DO88 is often the most discussed and appreciated component of the complete kit in part due to the technical prowess of DO88 and the relatively short sightedness of BMW with the original unit.
BMW M notably used the same transmission cooler for the DCT and 6spd. They blocked off some area of the leading air duct for the manual transmissions as they don't need the extra cooling.
However, the DCT is a wet transmission: the clutch forks' movements are activated by fluid pressure and the clutches are cooled with direct fluid heat transfer. These transmissions get hot - fast, and have a much higher cooling requirement than the dry clutch manual transmissions.
The OEM DCT cooler is fitted by the passenger side wheel housing, and is fed air from the bumper duct.
Ultimately, BMW tried a 2 in 1 product design. It has been fine for the street but not suitable for sustained high performance driving. DO88 tackled this product development with the goal of solving this DCT specific problem.
When compared to BMW's original cooler specifications, it is the most improved component of the DO88 kit. The core volume is increased by 217% with an increased fluid capacity of 110%.
The increase in active cooling area is 178%.
The core has 18 rows, increasing the heat transfer capacity of the cooler.
The Clubsport cooler retains the same mounting points as the original BMW unit.
The fluid connecting points are machined to fit the original lines and o-rings.
New carbon bumper ducts.
The original BMW M cooler was designed with ducts leading air flow from the passenger side bumper duct that were optimized for the original unit's cooling area. Unfortunately, the original duct would not suffice to maximize the potential of the larger DO88 unit.
A new bumper duct had to be designed and manufactured by DO88. They opted for pre-preg carbon construction. It's the lightest, stiffest carbon manufacturing process available and is used by OEM manufacturers and high end aftermarket suppliers.
The duct is made with 2x2 weave pattern and clear coated in high gloss.
The duct maximizes the available space behind the bumper to ram air onto the larger cooler.
It's well made - aligning neatly with the threaded sections of the cooler,
Up next: we fit the complete cooling kit to the S65-EVO, and get back to rev limiter testing.
Once the Stripper is back on the road, we will data log temperatures and document the improvements.
I can source the DO88 kits for your M car.
Leave a comment