I got around to this, they stated the following (below). Since most lesser expensive relays fail 'open' and not closed, I will be replacing the relay and boost reference switch in late 2021 .. most relays fail open, I don't need this shiny new engine getting the cylinders washed and scoured by a stuck-open 800ml meth spray since the indicator light only shows the boost switch status
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From:
NX Tech Help <Info@nitrousexpress.com>
Date: Tue, Sep 8, 2020 at 1:44 PM
Subject: RE: Question on the pump relay and physical boost reference switch ...
To: Topher Mc'toperton <topherme@gmail.com>
I've seen relays last 10yrs and on the other hand I've seen them last months. It's hard to say how long yours will last. If you wanted to do some due diligence I'd say replace the relay every 3-4yrs. Tech-SalesNitrous Express – Snow Performance
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