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You haven't linked to the thread mate

I think he's talking about this one:

http://mazda-speed.com/forum2/index.php?topic=2896.0

Why not just put a simple bleeder vcalve in if you want more boost?

Aren't you robbing vacuum/boost by using a bleeder valve? They bleed to atmosphere.
Your better off adjusting the wastegate linkage..... it enables you to attain another 1.5-2 psi without loss. Only hassle is if the dodgies have had a go at the linkage there often isn't the throw to keep the WG closed at low boost levels while gaining the extra up top.

Boris, you'll need to be really careful of your EGT and AF if you hold the WG closed at high revs man. One reason why the WG is there is to lower crown temperatures to avoid melting pots or burning valves.
Additionally, the highest vacuum will be in the TB due to the venturi effect.

Wòó

On my SP, I've re-located the vaccum/boost line from the exhaust maifold to the inlet manifold so that it reads boost after the intercooler instead of before the intercooler.
It does seem to have a little more low down boost, but the top end stays about the same, although my boost gauge does indicate I'm getting an extra half a pound boost.
The wastegate is now louder, for some reason, and throttle has become jerky when declerating while under boost.

In the end, I think it drove beeter with the line in it's original position, but there may be a smidgen more power the new way.

Woo wrote:Aren't you robbing vacuum/boost by using a bleeder valve? They bleed to atmosphere.

No because you will be increasing boost. the bleeder bleeds air out of the line that signal the actuator to open, which resuls in the actuator opening later.

Yes you will lose a small amount of air (less than 1.4 cfm) but the extra boost will make it unnoticeable. Even at the same boost you will make the same power. AT vacuum no air will be gained or lost.