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Vacuum Idle Pressure Average Needed/Trouble with Tial Q 50mm BOV

4.8K views 7 replies 4 participants last post by  boatsnhos  
first off, not trying to "disrespect" your choice of BOV or BPV, but just wondering why? is it a sound thing? They dont increase your performance any (I'd actually argue they are worse than a recirculating BPV, especially at your power level)...

Second, can't just swap on a BOV for BPV without addressing the tune for the car. IIRC you need to switch to speed density tune to run a BOV. Straight swapping without addressing the tune will make the car not run properly (as you have experienced).

http://www.iwsti.com/forums/2-5-lit...-motor/126267-read-before-you-create-new-thread-about-bovs-blow-off-valves.html
 
Yeah, the MAF is in the intake tubing, upstream of the intercooler, on our cars. If its just a noise thing, you can get that from an intake as well (again making sure you have a proper tune, or at least proper OTS map) for it, but aftermarket intakes will not yeild any real results until you hit BIG power increases...

Speed density is fundamentally different style of tuning, as opposed to the MAF based tune that the car comes with. I can't comment on the specifics of it since I'm not that knowledgeable in tuning though.
 
no problem! You may want to consider getting a cold air intake, as opposed to the SF intake, to have lower intake temps. The SF intake is known to run about 25-30*F above ambient temperature, where as the stock air box, and a full cold air intake are down in the single digits above ambient temp. I think cobb has a map for the AEM cold air intake.