| A number
of things contribute to cooling efficiency, e.g.; fluid capacity,
fin design, material, etc. Zionsville Autosport's Alloy Radiator
has a core thickness of 43 mm. The surface area of ZA's e38 - e39
alloy raditaor is 376 square inches - the same as a stock
radiator. Additionally, we 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.
The E39 M5 Super
Duty Cooling Kit... The alloy fan shroud and electric fan work
in concert to provide maximum cooling efficiency by pulling 2070
cfm through the radiator core - even while sitting still if
required by engine temperature. Simply hanging a fan on a core is
inefficient as airflow must be directed 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 to mention the fact that
hanging a fan through the core will eventually fatigue the cooling
tubes and lead to failure.
The alloy shroud in combination with the
electric fan creates a low pressure area behind the radiator in
order to pull air through the entire core surface. (The front of
the core is exposed.) The concept is a refinement of the BMW
design. Our kit features improved sealing of the shroud and
increased air flow without the parasitic drag of an engine-driven
fan. We have also been advised by both customers and technicians
that the engine fans are disintegrating at around 100k miles,
taking out the cooling system and damaging the hood of the car.
Our design incorporates a caged electric fan with a safety shroud
and lighter weight individual fan blades. The result is improved
safety and efficiency.
With regard to the expansion tank, we have been
advised and personally experienced tank failure through rupture of
the main expansion tank. Our thinking is that due to higher heat
soak temperatures on V8 and V12 cars, the tanks are heated/
pressurized beyond their limits. As a result, we designed an alloy
expansion tank with greater resistance to degradation caused by
the more extreme temperature limits in V8 and V12 cooling systems.
Our tank does incorporate some of BMWs features; e.g., we retain
the original cap and the internal plumbing.
The cap design is very clever: it facilitates
the expansion and contraction of coolant, while at the same time
offering an escape route for atmosphere and coolant when pressure
in the system threatens passenger well being * and cooling system
integrity. The topping off process requires filling the tank until
one half the level is maintained during the initial fill, then
topping off after a driving cycle, once the cooling system is
cold. As in all our radiators, the alloy construction of the
radiator also improves efficiency through an increase of radiant
surfaces and enlarged storage capacity.
With the 2 speed fan kit, the fan operates on
low speed or high speed based on engine temperature. High speed
comes on only when necessary. Running the fan through a resistor
allows us to back the speed down when the extra volume is
unnecessary, creating less wind noise.
* Otherwise, the heater core could rupture and
spray coolant inside the passenger compartment.
Lifetime Warranty!
Zionsville Autosport guarantees our radiators for life to the
original purchaser. Purchaser must provide proof of BMW coolant
use at first installation and once every two years thereafter.
Made in the USA with Euro Aluminum Cores. |
