Just recieved my forge recirc dump valve, But it came with 2x springs: green - 6-8psi yellow - 10-12psi Does anyone know which spring I should be using? It's going on to a 51 plate T4, but with a T2 engine - Running stock boost (at the moment) Not sure if it makes a difference but it also has a BSR exhaust system, and optiflow filter. Thanks
Green spring std tune. Yellow spring if you have it mapped.
go yellow bud
What will the yellow spring do with a standard map?
IIRC stock T4 is 16psi
According to the forge website the Psi ratings of the springs don't directly relate to boost pressure (would make life a whole lot easier if they did!)
[quote=lozccw;501853]According to the forge website the Psi ratings of the springs don't directly relate to boost pressure (would make life a whole lot easier if they did!)[/quote] it's the minimum boost you can run. I'd put the yellow (firmer) in first, you can always change it back if you don't like it. 2psi shouldn't make such a massive difference anyways.
I thought the dv/recirc pressures were 1/2 that of the boost pipes?
[quote=lozccw;501637]Just recieved my forge recirc dump valve, But it came with 2x springs: green - 6-8psi yellow - 10-12psi Does anyone know which spring I should be using? It's going on to a 51 plate T4, but with a T2 engine - Running stock boost (at the moment) Not sure if it makes a difference but it also has a BSR exhaust system, and optiflow filter. Thanks[/quote] There are TWO T2 engines! There is the B4194T2 200bhp or the B204T2 160bhp I think you have the 2litre one as that is year 2001 unless someone has done a change of engine I only mention this as the 1855 engine is good for a safe 19psi but the 1948T2 engine is only safe for 12psi as it has a high compression engine and you may have problems if you exceed it. The safe max. you can get out of the 2litre T2 is about 197bhp not quite T4 power. So having said that i would be careful what spring you use. The psi quoted is for the spring rate and NOT the boost pressure!
I have a S60R with a Forge recirc valve fitted. You are right about spring rates don't correspond with boost. When I fitted mine I had the green spring in. To test how much boost this spring would hold I pulled the pipe off the recirc valve and blanked it. I have a very accurate boost gauge. With the pipe disconnected the spring was the only force keeping the valve shut. My car is mapped and will boost to 1.35 bar but I can make it peak to 1.5 bar if I stamp on the loud peddle for a few seconds. I drove the car aggressively and it held 1.0 bar on its own. When I lifted off (with no pressure or vacuum side of the valve) the valve opened to release pressure. I now have the yellow spring fitted and as yet I have not had time to test this one. Guessing I would say it will hold 1.3 bar under the same test conditions. Hope this helps. Dave
These are the Forge spring ratings for the DV/RV. [COLOR="Lime"]GREEN[/COLOR] - up to 10psi. [COLOR="Yellow"]YELLOW[/COLOR] - 10psi - 16psi. [COLOR="Blue"]BLUE[/COLOR] - 16psi - 22psi. [COLOR="Red"]RED[/COLOR] - 22psi and up. The valve comes supplied with the green spring fitted. This is the same as oe.