stock BOV's?
 

Do you have to recirculate them?

typically a turbocharged car with a maf recirculates the air. so if you dump to the atmosphere you run rich between shifts because the air is already measured.

so when you get an aftermarket BOV you have to do something with the MAFS

nope. a lot of aftermarket bov's have a recirc. kit

Do you have to recirculate them?
 

Yes, you will need to recirculate a stock SR20 BOV because it typically leaks under boost pressure; hence; having your car bog out on you at about 4000 RPM. As for most aftermarket BOV's it is not necessary to recirculate it but it would be best.

cheapest way to go, get 1g dsm crushed bov. Should hold up to aboot 18 lbs of boost.

cheapest way to go, get 1g dsm crushed bov. Should hold up to aboot 18 lbs of boost.
 

Yeap! You can do it that way; however, I don't think it's that big of a deal recirculating the BOV. The recirculating type was only made for Emission purposes, it's not out there to destroy your engine.

I don't seem to notice any major richness between shiftings having my GReddy BOV recirculate; besides, you would rather have you car running rich anyway because running lean in anyway can cause your motor to blow.

If you DO NOT recirc. you run rich between shifts