Here's an update on the upcoming Signature Thumper Heads for CVO, Jims, and standard Twin Cam style castings. We've been saying that it's coming soon but we do have all the final programming done. This is one of the first three sets we're running through - here we're doing an upgrade for a Jims head. How we do this is - we raise the intake ports on these heads to create a better short bend radius and raise the back of the port to create a better radius behind the guide. To do so, we have to relo

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