Blower Identification

To determine what size blower you have measure the blower housing.
Do not measure the end plates, housing only.

Below is a picture of a 9" supercharger.

Another easy way to identify the blower is to count the cooling fins.

• 4" Blower: 2 fins
• 5" Blower: 4 fins
• 7" Blower: 7 fins
• 9" Blower: 9 fins
• 12" Blower: 15 fins