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1 x 1/8" NPT 1/4" Barbed Nipple (Male Fitting) - $1.00
1 x 1/8" NPT 1/4" Barbed Nipple (Female Fitting) - $1.00
1 x 3/16" Ball Bearing - $0.15
1 x Utility Spring - $0.30
2 x 1/2" Hose Clamps - $0.75


The barbed fittings you get should screw onto each other in opposite directions with a nipple on each end... You will essentially place the spring and ball bearing inside the fittings in such a way so that the spring presses the ball bearing firmly against the inside of the fitting to seal the hole off.

If the spring is too short then you may need to pull on it and stretch it longer. If its too long then just cut a bit of the spring off. The spring should press the ball firmly into the seat when you assemble the two barbed fittings together.

Also, you might want to flare out the ends of the spring so that is 'cups' the ball on one end and so that it can not press itself through the nipple on the other.

Then once you got it all working correctly, you should be able to adjust the boost by the amount of turns you screw the fittings together, you can test this, but blowing in the nipple that has the ball bearing pressed against it. If you can blow through, then keep blowing while turning the fittings and you should feel the ball pressing tighter and it gets harder and harder to blow through until finally you can't blow through any more..

Also, the fittings are pipe threads too, so at some point you'll need to get a wrench out to tighten it further...


To install it, make sure you have the ball bearing side towards the manifold or VAC source and the spring side towards the wastegate, so that the boosted air PUSHES on the ball bearing.

Use mini clamps and clamp it down tight and your good to go..

Start off with the fittings screwed in loose so that you can blow through it yourself, then take it for a drive, slowly tighten it up until you get the boost you want and you're set!

If you tighten the fittings as much as you can and your still not getting enough boost, then just take it apart, and pull on the spring to make it longer, that way it'll push harder on the ball bearing.
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