FAQ’s

Please consider these important tips before ordering an automotive electric fan.

  1. What is the make, model and year of your vehicle?
  2. Will the vehicle be used to drive on the street, race, or off roading?
  3. Will you replace the engine fan with an electric fan or do you want a pusher fan while still using the engine fan?
    • If a puller fan is to replace an engine fan, you need to know the distance (in inches) from the water pump to the radiator core. When using only an electric fan, use the fan with the highest cfm whenever possible or use the Sidewinder Electric Fan Kit.
  4. What is the width and height (in inches) of the radiator core (not including tanks)?
    ____” W x ____” H
  5. Is the radiator a cross flow (tanks side by side) or down flow (tanks on top and bottom)?

DOWN FLOW/SHROUDS

Down flows typically use a 16″ fan or two smaller fans.

IMPORTANT: Allow an additional ¼” when using our mounting brackets. Shrouds cannot be used on a pusher fan.

Adding a shroud puts a fan 7/8″ closer to the water pump. If the core is larger than 20″ x 24″ then two electric fans work best. Fans come in 2 ½” or 3 3/8″ thickness. On a 16″ fan, the top of the fan shroud to the bottom of the fan motor measures 11″. Below the fan motor you will need approximately 2″ between the water pump and core for mounting the fan. Down flows with core sizes wider than 20″ or taller than 24″ work better using a custom shroud.

PUSHER FAN

Pusher fans with straight blades must be spaced out ¼” from core or fan mount bars. Pusher fans that go onto AC condensers can be attached with plastic ties and cut off at the condenser.

IMPORTANT: Do not put plastic ties through the radiator, as it will cause the radiator to leak.

Pusher fans should be the same diameter or smaller than the A/C condenser. If they are larger the air will pass through the open area. For either a pusher or puller fan, one large fan (14″ – 16″) typically works better than two small fans (10″ or smaller). If you are able to use two pusher fans (12″ or larger), two generally work better than using only one large fan. When the pusher fan is a helper, one (11″ or larger) fan will work best, or you can use two (10″ or smaller) fans if you have room. When a pusher fan is the only fan being used, select a fan or fans that will cover up as much of the core as possible.

FAN SWITCHES

When selecting a fan switch, The Fan Man’s switch kit works great. For a 160º thermostat use an 185º or 195º switch. For a 180º thermostat use a 195º switch. For a 195º thermostat use a 210º switch.

IMPORTANT: If running two fans with 13 amps or lower use a 30-amp circuit breaker instead of a fuse, otherwise the fuse may blow. If you are using two fans that require 14 or more amps then use 2 relays with one thermal switch.

MOUNTING KITS

Use our fan mount kit, part FMK for installing electric fans and avoid plastic push ties that can damage the radiator.

FORD CARS

Year Core Dimensions Recommended fan set up

  • 1928 – 1929 18H x 18W 1 fan pull only
  • 1930 -1931 21H x 18W 1 fan pull only
  • 1932 22H x 17 3/8″ W 1 fan – can have small pusher
  • 1933 – 1939 22H x 17W 1 fan – can have small pusher
  • 1940 -1941 19 1/8H x 21W 1 fan – check clearance – pusher okay – can be larger
  • 1946 – 1951 20 1/2H x 20W 1 large puller or pusher
  • 1955 1 puller or pusher

FORD TRUCKS

Year Core Dimensions Recommended fan set up

  • 1928 – 1929 18H x 18W 1 fan pull only
  • 1930 -1931 21H x 18W 1 fan pull only
  • 1932 22H x 17 3/8″ W 1 fan – can have small pusher
  • 1933 – 1939 22H x 17W 1 fan – can have small pusher
  • 1940 -1941 19 1/8H x 21W 1 fan – check clearance – pusher okay – can be larger
  • 1946 20 1/2H x 20W 1 large puller or pusher
  • 1949 – 1951 Needs shroud with 1 large fan or 2 small fans
  • 1955 – 1957 Needs shroud with 2 small fans

CHEVROLET

Year Core Dimensions Recommended fan set up

  • IMPORTANT: Need core sizes and distance from core to water pump.
  • 1955 – 1957 car Pusher only unless on 6 cylinder side than 1 large fan
  • 1955 – 1957 truck Needs shroud for puller – 1 large okay for pusher

CROSS FLOW/SHROUDS

You must know the core size.

IMPORTANT: Most cross flows will be 15″ to 21″ tall. If smaller than 21″ in length then one larger fan will work best for a puller fan.

For greatest cooling efficiency, use a fan 3 3/8″ wide when there is room. If core is larger than 22″, then two small (11″ or larger) can be used with a shroud. When adding a shroud with one fan, add approximately 7/8″ between the water pump and radiator. When adding a shroud with two fans, allow approximately 2 3/8″ between the water pump and radiator. Running two electric fans allows for more space next to the water pump than running one, with or without a shroud. Cores larger than 24″ in length can use two fans (12″, 13″ or 14″) depending on size of core.

FLAPPER VALVES/SHROUDS

Flapper valves are added to the shrouds when needed to allow excess air from high speed driving to exit fan shroud. Without flapper valves, too much air enters into the shroud causing the air to go around the radiator instead of through it, resulting in the car overheating. If a pusher fan is the only fan used, cover as much of the radiator core as possible. Remember, shrouds cannot be used on pushers. Fan shrouds need a way to mount to the radiator. The radiator is needed in order to make mounts for the fan shroud. Fax a drawing of your radiator to Mattson’s Inc. at (714) 893-4933 if you want a quote from us to build you a custom shroud made that will fit your mounts.