Sequential/BOV Question
 

My CRV (Correct acronym right?) leaks at part throttle, I believe this is due to a vacuum problem at the solenoid. If I go more than 1/3 or 1/5 throttle, it closes and builds boost just fine. My question is, can I just hook the vacuum hose that controls that to something like the UIM nipple and run it like a BOV? It would be a temporary fix to my boost problem, but would it have any side effects to the Sequential system? I know its supposed to vent pressure during the 4500rpm changeover, but would changing that have a detrimental effect on the motor? Thanks.

The CRV doesn't vent at 4500, it's closed at that point.

The CRV vents below around 4000 during pre-spool. Your secondary turbo is pre-spooling while the primary is online. However, it's basically spooling into a brick wall. The CRV is there to vent off some of the excess to the turbo isn't overworked while it's not online.

The CRV should close around 4000 or so RPMs to allow the secondary to build boost to come online. So, from 4000 and on, it should be closed.

But is running it like a BOV instead of its intended purpose bad? Is that venting before 4k vital? Would anything break if I bypassed its control solenoid, and as I said, just run it off of a vacuum nipple on the UIM, and used it as a standard BOV?

While the CRV and ABV (BOV) are similar devices, their uses are opposite.

Keeping the CRV closed the whole time would overwork your secondary turbo (i.e. shortening it's lifespan). Shortening by how much? I don't think there will be an absolute answer to that.

It's best to fix the problem properly than to "work around" the problem.