Was just curious really if anyone noticed any difference or should notice a difference swapping. Currently the car has only got an induction kit and back box chop, but I will be getting the car mapped soon. Anyone done the above, thoughts would be great
Difference as in what? The recirc valve offers no performance gains whatsoever The different springs are only used to control when the valve opens on throttle-close operations, or the position of the valve in mid-throttle applications. For instance, a stronger spring lets the valve open later when you let go of the throttle as more pressure has to be build up in your intake piping before the valve opens. Too strong springs will result in the valve not opening anymore at all at throttle-close applications, causing the excessive boost pressure to come back out through the turbo's compressor wheel instead of recirculating through the valve; this causes the "tshhh-tshh-tshhh-tshh" sound (blades of the compressor wheel running into your excessive pressurised air going back through the intake).
You need to know what boost pressure you'll be running once mapped, then fit the correct spring to suit. I think you'll need a yellow spring for a stage 1 map.
Cheers gray. I've read about putting a ten p behind the spring but that's a bit Pikey even for me lol.
Boost pressure doesn't really have much to do with it. Any increase in boost pressure is also seen at the otherside of the valve. Technically, having no spring would mean that the valve would be closed since the pressure differential would be 0. The spring is only there to keep the valve from 'floating' in an opening state and provide just enough pressure to keep it closed. Both springs work fine. The stronger spring might show slight compressor flutter at lift-off, but that is negligeble.
Fitted and driven with the spring in for over a week now. The car drives really really well. Definatly more noise and the performance seems to have gone better.
