Guys, just fitted this DV, and although the spring felt pretty good when off the car as soon as a vacuum is on it its opening. https://www.youtube.com/watch?v=PBHzLeSec3A&feature=youtu.be Any other opinions before I start looking for a replacement spring?
Normal operation to be open when the vacuum pipe is connected on tick over? I was expecting it to be closed?
If its open and allowing air to pass on idle it's not normal. Stronger spring or shims will defiantly help.
Not trying to jack a thread but I have a forge dv that i purchased second hand and makes the same noise as this one in this video : https://youtu.be/W4brqpuU7Pk I don't want the valve anymore but I did see a servicing kit I can buy to fix it ready for sale if that's what the problem is
Looks like a single piston one, now ive watched the video on a larger screen, a Baileys DV34? It will work but will allow unfiltered air into your engine. The DV36 is twin piston and will stop this or just get a stronger spring so this one only opens with vacuum on the small hose and positive pressure pushing on the piston.
Cheers guys I think it may be single as you say James, as its off my Saph Cosworth from a few years ago. I don't want to be letting in unfiltered air, especially as it may throw out the A/F? Do you think a stronger spring would do it? if not ill have a look around as I have a few others I can try, although I expect they will all be single piston given the age.
A stronger spring will work but if you go too strong it might not open when you want it too If your not running enough boost. A lot of kits come with shims so you can fine tune it.
