BMW E46 M3 Oil Cooler Kit 2001-2006

Interested in purchasing this E46 oil cooler? Check out our product page for more information!

Mishimoto BMW E46 M3 Oil Cooler Kit

The results are in and they are exactly what we expected! This cooler provided huge gains in cooling efficiency. Let's take a look at the data we compiled. First up is the core volume comparison.

Core volume comparison

As you can see, the Mishimoto oil cooler provides a huge increase in total core volume. The fluid capacity for the stock cooler is 0.34 qt, while the Mishimoto cooler holds 0.78 qt. This is an increase in volume of 152%!

The additional fluid capacity will add 4 lb to the front end of the vehicle. Although not a huge number, we still needed to check if this added weight would produce any issues with the mounting brackets and stress-related failures. Our team used Finite Element Analysis (FEA) software to ensure that the bracket would support the added weight.

FEA bracket stress testing

This analysis reveals any areas of the component that will

Interested in purchasing this E46 oil cooler? Check out our product page for more information!

Mishimoto BMW E46 M3 Oil Cooler Kit

Time to see if this cooler can make a significant impact on fluid temperatures. As before, we borrowed a test fit vehicle from the folks over at Open Road Tuning. Once we had the car on the lift, we removed the factory cooler lines and spliced our temperature sensors into the stock lines so we could collect inlet and outlet fluid temperatures.

Temperature sensors installed

Laptop prepared for data collection

Once everything was installed and checked for leaks, we hit the road. The testing conditions below were followed for both the stock cooler and the Mishimoto oil cooler prototype.

Testing Conditions

• Ambient temperature: 69°F-70F° (20.5˚C-21.1˚C)
• Humidity: 20%
• Sensor: PLX temperature sensor reading 10 times per second
• Driving conditions: 65 mph highway, cruise for 5 miles (special attention given to vehicles driving in front of the M3 to assure fresh airflow

Interested in purchasing this E46 oil cooler? Check out our product page for more information!

Mishimoto BMW E46 M3 Oil Cooler Kit

Welcome to our third installment of the build! We are nearing the completion of this project, with only some final test fitting necessary and data collection to ensure that this product performs to our standards. First, take a look at the Mishimoto oil cooler compared to the stock unit.

Mishimoto prototype oil cooler (right) and stock oil cooler (left)

Mishimoto prototype oil cooler (top) and stock oil cooler (bottom)

Mishimoto prototype oil cooler (top) and stock oil cooler (bottom)

Mishimoto prototype oil cooler under stock oil cooler

The Mishimoto oil cooler is massive compared to the stock unit. Greater size will provide improved capacity that will aid in reducing temperatures. Additionally, the Mishimoto cooler is constructed using a bar-and-plate core that our engineering team designed. This core will provide improvements in heat transfer compared to the

Interested in purchasing this E46 oil cooler? Check out our product page for more information!

Mishimoto BMW E46 M3 Oil Cooler Kit

Our team now had a functioning oil line adapter to convert from the stock oil filter housing to -AN fittings. Now we would be able to move forward with designing the actual heat exchanger for our kit. We reached out to a few of our local friends and sourced this Oxford green example!

Test vehicle on lift

Our friend Andrew at Open Road Tuning was kind enough to loan his vehicle for a week of development! First we tore off the stock cooler to get a look at what kind of space we had to work with.

Stock oil cooler removed

Our engineers set to work gathering dimensions and collecting data for mounting points. After reviewing some of the specifics, we made the decision to ditch the stock cooler shroud in order to maximize the size of our cooler with the space given. After collecting our dimensional information, a prototype was created in 3D and can be seen in the

Interested in purchasing this E46 oil cooler? Check out our product page for more information!

Mishimoto BMW E46 M3 Oil Cooler Kit

The BMW S54 won the "International Engine of the Year" award at its inception in 2001 and was consistently on "Ward's 10 Best Engines" list for four years. It's hard to argue against the E46, an 8,000 rpm, 3.2L straight-6 producing over 330 hp and 260 ft-lb of torque, with a competent chassis, an exhaust note that straightens the neck hair of all within earshot, and a body styling that is unmatched in uniqueness. Although my opinion is slightly skewed, being a fan of most BMW products, many would agree that the E46 was a fantastic vehicle for the street and even better for the track. E46 M3 pricing has trickled downward over the past few years, meaning that even those on a tighter budget can find their way into the cockpit of one of BMW's finest. We are seeing these vehicles at track days, drift events, parking lot autocross battles, and at the drag strip.

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