Hi everyone, can you make them louder???? It might sound stupid but i want them to be louder. Has anyone tried anything???? What if i was to disconnect the pipe that goes from the bov to the intake and block the intake side of?? Will that make a difference???
stock recirc valves cannot be made louder. By design, they are supposed to recirculate the air back into the intake system, prior to the turbos. Yes, you can remove the piping that connects them to the factory intake recirc points, but dont know what kind of noise they will make. Atmospheric bov's by design, have differing styles of trumpets, outlet vents etc to give differing noises on release. No idea what a plain pipe outlet will do. You are obviously aware of the legalities of atmospheric BOV's? and dont be fooled into thinking that if they are located underneath the nose panel, an inquisitive Traffic Branch Officer wont request you remove it for inspection. The fine isnt pleasant, and it gives them reason to look further over the vehicle for additional defects...... dont ask me how I know That and the air released is metered via the AFM, and assumed to still be in the intake system via the ECU, thus a momentary enrichening of the A/F ratio with every release. Personally, didnt notice a negative difference from this. Give it a go, at the very least it will cost you is a couple of rubber caps- redily available from Bunnings or a furniture store as table leg caps, and 2 hose clamps. At the very most, it will cost you thousands of $$$, a day in court, and your vehicle de-registered.
you can get away with a bit of air being vented as far at the afm being out but some factory bovs are even open at idle which will case problems , you can rig up a set up to bleed in some more air so they dont . The cops arnt going to pull appart you car to find them and they cant make you but like always they have there standard unnessesary noise fine .
your doing it rite its just that air is being read in the afm and not going to the engine so it goes way rich , the only proper way to solve that is get a ecu that runs a map sensor but you cal also try this the problem might be that they are open at idle or to close to it , most aftermarket valves take more vacuum to open than factory ones , you might need to make it so the bov sees less vacuum but putting a restrictor in it then a valve on a t peice , that will make it open later and close earlier .
the stock blow off valves dont fully close properly they are desinged that way so there is nothing wrong with them and thats why the car stalls. Kev
Putting a pod filter on mine made the stock BOVs more audible. Switching to Z1 replacements set to recirc also made a nice improvement
If you're despirate for the noise and dont want to fork out $400+ for a pair of BOVs just do the "Sticky Mod" and make a tube to run between the two outlets, cap off the loose ends and weld a single BOV onto the tube. Kinda dodgy but this should only cost around $100 if you use a cheap $80 SCA BOV and some aluminum/steel tube (Note: Sticky used part of the frame from an old bicycle). Or alternativly fork out the money and get some decent recircs or BOVs and do the job properly.
This technique will NOT work. And will always give you the same results as you've just experienced (nearly stalling). Reason is the stock recirc plungers aren't spring loaded like aftermarket BOV's. They rely on the engines vacuum to close again after they've been released. This is the purpose of the recirc line that you're essentially removing to make the noise. End of the day, if you want the noise, you'll have to cough up the dosh and buy some BOV's.
