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Radium Coolant Expansion Tank Lotus Elise Exige Oem Location

Radium Coolant Expansion Tank Lotus Elise Exige Oem Location

Regular price £334.20 GBP
Regular price £446.09 GBP Sale price £334.20 GBP
Sale Sold out
Tax included.

SKU: 20-0270-01

Radium Engineering S2 Lotus Elise, Lotus Exige, and Lotus 2-Eleven comes standard with a Denso coolant expansion tank. This is the same plastic tank that is found in the Toyota 2ZZ-GE equipped vehicles. For fitment, Lotus designed a complex bracket that incorporates a mount for the electric hot-soak water pump. There has been cases reported where the Denso tank has failed and owners have found that new replacements are quite expensive. Radium has simplied the Lotus design by making two separate mounts and further improved it using a robust aluminum tank and adapting the factory hoses to -6AN fittings.

The mount uses all factory threaded mounted holes. Because of this, there is no need to drill or modify anything as it bolts in. Install is a fairly simple process that can be performed by an average mechanic. Everything is accessible with the rear clam intact. Aluminum push lok-hose ends are included to convert the factory coolant hoses into -6AN.


-Billet Aluminum Coolant Tank Anodized Black
-Nickel Plated Sight Tube Fittings
-Aluminum 6AN Male Adapter Fittings Anodized Black
-Aluminum 6AN Hose Ends Anodized Black
-Laser Cut Aluminum Tank Bracket Powder Coated Black
-Laser Cut Aluminum Hot-Soak Water Pump Bracket Anodized
-Rubber Isolation Coolant Tank Grommets
-Hot-Soak Water Pump Cushion Clamp
-Mounting Hardware


The optional Radium Engineering pressure caps (sold separately) allow the user to select a range of pressure that was not possible with the Denso tank. The purpose of a high pressure cap is to increase the boiling point in the cooling system providing improved cooling efficiency. Each cap is manufactured from stainless steel with a race proven high pressure valve. This is something to consider when tracking the vehicle in extreme conditions

Note: The OEM Lotus pressure cap is 1.1Bar.

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