Playing with dump valves

[Alex]

Over the weekend (in between the rain) decided to change from the open circuit dump valve back to recirculating one to see the effects.

Apart from losing the cool/annoying (depending on mood) sounds beloved of Max Power readers I've notice more boost is retained on gear changes, a good 1/4, 1/3 orange boost is registered imediately on reopening the throttle, and more importantly it seems easier and smoother when feathering the throttle when driving Welsh B roads.

Strangely the atmospheric dump valve makes a completely different noise fitted to my friends 9000 compared to my 900.

[90t16Saero]

Interesting stuff. What dump valve have u got as im in the process of upgrading my car.

[Alex]

The atmospheric dump valve that I've currently removed was a Bailey Evo DV26. Replaced at the moment with a Group A spec item that I purchased from Turbo Dynamics several years ago featuring an aluminium body and kevlar diaphragm.

The valves made by Forge (www.forgemotorsport.co.uk) have a very good reputation for build quality.

These are the people that make the Trent Saab uprated wastegate actuator for the TE05 turbos.

[my kraia]

Yeah I'm thinking aboutu putting another blow off valve on my 900T spg. I hear they keep the turbo spooled up. Is that true. Also that release nosie is kind of cool, but I could see how that would get annoying. Why doesn't my car make that sound now? Any suggestions on a good valve to get and where?