I want to share the joy and pleasure I have found with my first, and so far, only, performance "mod" - the g-valve (aka grainger valve, aka manual boost controller/MBC, aka Dawes Device).

I know some of you already have one of these do-dads installed; others may think they already have enough get-up-and-go in their turbocharged Volvos.

For the rest of you... the g-valve costs around $40 (or you can make you own for less), takes maybe 15 minutes to install, and will change the personality of your car. It lets you to adjust the maximum boost your turbo makes (stock is around 7 psi; right now I top out at 9 psi), but it also makes the turbo kick in at low boost very quickly in partial throttle (normal) driving.

It's highly recommended that you also install a calibrated boost gauge, so you can accurately measure the changes you're making.

Here are a couple good g-valve resources:

Gus Mahon's boost controller page
Dawes Devices, which sells g-valves

and some shots of my install:







Happy boosting and drive safely!
- Brian '93 945T