Newbie question...

My 2003 225hp Roadster now has a GIAC tune, Neuspeed P-flo intake, Samco turbo inlet, and Forge 007 DV. I'm just thrilled with how much more the car responds now! Hoping to go with a 3" downpipe as the next improvement.

I installed a boost gauge this weekend, and am interested in tweaking my DV to hold/dump properly.

Right now it has the weakest (green) spring installed which is supposed to support 5-15psi. At typical driving I'm typically boosting around 10-12psi, but I've also seen it spike to 22-23psi at peak times before dumping... It generally dumps when I let off the pedal, but occasionally dumps on it's own.

The tuner who installed my GIAC, reversed my Forge DV (backwards) to get a better response from it. Not sure if that's the best thing or not... Forge says it's not designed that way, and said some people have reported this helping... I'm inclined to put it back into it's suggested orientation.

I have the spring kit, but am not quite sure yet if going to the yellow spring rated for 15-23 is a better choice, or if maybe just a spacer on the green one, or nothing is needed.

Any feedback would be appreciated! Just starting to learn how this works and what to watch for....

 

I use the Yellow spring and I have also relocated the DV to the front cold side.
DV relocate kit, Keeps the DV so much colder and adds longer life of the DV.
I'm not a big fan of the backwards DV. Some say it works, but nah! JMO.

 

you want the softest setup to hold the boost. A green spring or green with a shim or 2 is softer than a yellow spring and will suffice.

Also, the dv on the cold side wont extend the life... its billet aluminum and brass. They dont go bad. The only thing that can go bad is the springs from use.

As for reversing the dv, the stock orientation allows for softer spring tension for faster reaction

 

I also had a chance to touch base with Forge..

They recommended going with the the yellow spring (or green wiht shims) as well. And they pretty much say the same thing about orientation to ensure a good reaction time with the softest spring to match the peak boost.

Now that I'm a little more "edumatcated" I'm going to return my DV to it's upright position, and then do a few test with green, shims, and yellow and see how it goes....

Is there particular orientation for the shims? On top or on bottom of spring?

 

You just remove the top and spring and then add the shim(s). Otherwise it would be more difficult to add shims on top of the spring.