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Choosing the right silicone hose size is important for creating a secure and reliable connection. Whether you’re replacing a coolant hose, modifying an intake system or creating custom pipework, a few simple measurements will help you find the right fit.<\/p>\n
The most important thing to understand is how silicone hose sizes are measured.<\/p>\n
Is a Silicone Hose Measured by Inside or Outside Diameter?<\/strong><\/p>\n A Silicone hose is normally sized by its inside diameter (ID).<\/p>\n For example, a 51mm silicone hose has an internal diameter of approximately 51mm. This is designed to fit over a pipe or connection with a corresponding outside diameter.<\/p>\n Don’t measure the outside diameter of an existing hose and use that as your hose size. The external measurement includes the thickness of the silicone walls and will therefore be larger.<\/p>\n How Do I Measure for a Silicone Hose?<\/strong><\/p>\n The simplest method is to measure the outside diameter (OD) of the pipe or fitting that the silicone hose will connect to.<\/p>\n If your pipe has an outside diameter of 38mm, for example, you would normally choose silicone hose with a 38mm internal diameter.<\/p>\n For the most accurate result, use a digital or vernier calliper. This is particularly useful when you’re unsure whether a pipe is a common metric or imperial size.<\/p>\n The hose should fit snugly over the connection without being excessively loose or needing to be heavily stretched.<\/p>\n What If the Pipes Are Different Sizes?<\/strong><\/p>\n If you’re joining two pipes with different outside diameters, you’ll need a silicone reducer hose.<\/p>\n A reducer has a different internal diameter at each end. For example, a 63mm to 51mm reducer allows you to connect 63mm pipework to a 51mm connection without needing additional adapters.<\/p>\n Reducers are commonly used in custom intake, intercooler and cooling systems.<\/p>\n Do I Need a Straight Hose or an Elbow?<\/strong><\/p>\n Once you’ve established the correct diameter, consider the route your hose needs to follow.<\/p>\n Straight silicone hoses are suitable for connecting pipework in line, while 45-degree and 90-degree silicone elbows can be used when the connection needs to change direction.<\/p>\n Other options include 180-degree bends, reducers and hump hoses. Choosing the correct shape helps create a cleaner installation and avoids putting unnecessary strain on the hose.<\/p>\n How Do I Measure an Existing Silicone Hose?<\/strong><\/p>\n If you’re replacing an existing hose, measure its internal diameter, overall length and any bends.<\/p>\n For a shaped hose, check the angle of each bend and the length of the hose on either side. If the hose changes diameter, measure both ends separately.<\/p>\n It’s worth taking these measurements before removing or disposing of the old hose, as it provides a useful reference when selecting the replacement.<\/p>\n Don’t Forget the Hose Clamps<\/strong><\/p>\n You’ll also need to choose appropriately sized clamps.<\/p>\n Remember that silicone hose sizes refer to the internal diameter, while a clamp fits around the outside. A 51mm silicone hose will therefore have an outside diameter greater than 51mm.<\/p>\n Check the adjustment range of your chosen clamp to make sure it accommodates the external diameter of the hose.<\/p>\n What Size Silicone Hose Should I Order?<\/strong><\/p>\n As a general rule, measure the outside diameter of your pipe and choose a silicone hose with the same internal diameter.<\/p>\n Then select the appropriate shape, length and configuration for your installation. Getting these measurements right before ordering will make fitting easier and help create a secure, professional connection.<\/p>\n Find the Right Size at Viper Performance<\/strong><\/p>\n Shop Viper Performance silicone hoses in a wide range of sizes and configurations to find the right fit for your vehicle.<\/p>\n","protected":false},"excerpt":{"rendered":" Choosing the right silicone hose size is important for creating a secure and reliable connection. Whether you’re replacing a coolant hose, modifying an intake system or creating custom pipework, a few simple measurements will help you find the right fit. … Continue reading