swap from diverter valve to true into the atmosphere, BOV

i have a 99 eclipse gs-t with a stock diverter valve. tomorrow i'm installing a true into the atomosphere suquential BLOW OFF valve. i have heard that not recirculating the air causes problems w/ air/fuel running too rich. what can i do BESIDES buying an aftermarket diverter valve, AND besides reprogramming my car's ECU? or is what i have heard false? i want to install it tomorrow and i've been waiting for this for months putting an SQV on my car... please any help ASAP...

also, why is it that when i punch the gas on my car in any gear, it hesitates and doesnt accelerate properly unless i push the pedal "not so fast", almost like it's getting too much air and not enough fuel, but there is no check engine light on. it also does it if i go from say, first to fourth and my rpms drop to like 2 grand in that high gear it does it too, what is this

The slamming on the gas could be bad spark plugs. Check them for fouling and just replace. Also what kind of plugs are you using? It may also be that as you slowly push the pedal down, the rpms are rising and building boost so it just seems like it's doing more than slamming the pedal down. Check plugs though.

Dumping to atmosphere is not good unless the car has the mods to support it. You will run very rich. The turbo guys will tell you what you need, but this topic has been done over many times. If you do a search you will find the answer. I believe a GM MAF is need so it reads the pressure/air before the BOV, and not after it. Stock, the recirculated air gets read by the car, so it needs to see it if left stock. Someone hit me if I'm wrong.

Dave is right. I would not put that BOV on your car unless you have the stuff to recirculate it. Its only going to make your car run worse. And you should also do a tune up. Make sure your car is running good before trying to mod it.