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Supercharger Blow-Off Valves - All MMM Models

R Type Supercharger Blow-Off Valves - All MMM Models
R Type Supercharger Blow-Off Valves - All MMM Models

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We now make our own blow-off valves as part of our increased manufacturing independance programme. We are the only supplier of the R Type blow-off valve which is the period design for all blown MMM applications.

The difference in the R Type blow-off valve compared to modern reproduction MMM valves are:

  • The R Type design has a longer neck and shorter body.
  • We incorporate the original factory 'BA' lettering on the side of the body.
  • The internal bore is formed by a cored pattern method as opposed to machining.
  • We incorporate an integral spring centralising locator in the top.
  • Our outlet flange is drilled and tapped (as per the original) for optional fitting of a blast defector plate.
  • We cast these in LM6 aluminium to produce a strong casting with a highly polished finish.


Over time, reproduction manifolds seem to have adopted a range of hole centre distances for fitting of the blow-off valve. There is often an incompatability problem relating to products of different origin. Therefore, we have jigged up to supply blow-off valves with a range of centre distance options to include 2 1/4 inch, 2 3/8 inch, 2 1/2 inch and 2 5/16 inch. We can also incorporate hole diameters of either 1/4 inch diameter or 5/16 although the 5/16 bolt head cannot be used in conjunction with a 2 1/4 inch hole centre distance.

We also manufacture J and P Type Jackson design cylinder head inlet manifolds and Ki-gass atomiser jets and supply Wellseal jointing compound.

As well as being used on the cylinder head inlet manifold, the 'Volumex 7 fin' supercharger manifold has been designed to accommodate an optional secondary inverted blow-off valve subject to machining of the underside diamond boss. The closer a blow-off valve is mounted to the supercharger, the better chance the blower has for avoiding damage through pre-ignition.

For customer's wishing to fit one of our blow-off valves to our 'Volumex 7 fin' manifold, we will undertake the necessary machining at a nominal cost.




Price 118 each (please specify distance)




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Website last updated Dec 03 2018

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