Our e34 532i project inspired another custom cooling solution for the 5 series. This setup is designed to work in manual transmission cars from 1991 through 1995. The later automatics did away with the internal transmission cooler. As such, the 1993 through 1995 automatics are also valid candiates for this cooling package. Of course, if you have an S50 or S52 stuffed into your e34 chassis, that would be just fine, too!

Our alloy radiators use a high efficiency core similar to a stock radiator. High efficiency cores have more fins per inch, more tubes per core and more cooling capacity. Each row has a single, large tube. The flat side of the tube is in direct contact with the fins which transfers heat from the tube walls to the fins. Since the rounded ends of the tube are not in direct contact with the fin, this portion of the tube does not aid in secondary cooling. The more tubes per row, the more rounded ends, and the less direct contact there is between the tubes and the fins. ZA uses a single tube for better heat dissipation.

Cooling improvement also comes from larger radiant surfaces on the tanks. The alloy tanks themselves have a high level of thermal conductivity which helps to dissipate heat into air instead of back into the engine. The glass reinforced nylon used in stock tanks just doesn't compare.

The E34 525i Super Duty Cooling Kit is designed for BMW owners who want the best. This is the ulimate cooling solution for your 5 series. In addition to the benefits of an all alloy radiator, the kit includes an alloy fan shroud, alloy overflow tank, aluminum cap and a 16 inch Spal electric fan.

The alloy fan shroud and electric fan work in concert to provide maximum cooling efficiency. Simply hanging a fan on a core won't do. The airflow must be pulled through the entire core area, not just directly in front of the fan. The latter approach limits the effectiveness of the core. Essentially, it reduces the core size to the diameter of the fan. Not a good practice. The alloy shroud in combination with the electric fan creates a low pressure area in order to direct airflow over the entire core surface. Additionally, this setup allows for the removal of the engine driven fan and clutch as well as the auxiliary fan in front of the radiator. BMW retail price on these items is over $700! Our kit eliminates the need to replace these expensive factory parts.

By replacing the stock plastic overflow tank, the our kit affords an extra level of protection. The stock overflow tank has the potential to become brittle with time due to constant temperature cycles. The seal between the stock overflow tank and radiator is a known weak spot. The alloy overflow tank eliminates these design deficiencies.