mcmaster manual boost controllers
 

EDIT: Both are pending sale.

$20 (each, I have two) shipped. Price is firm since it's not much more than shipping and parts costs. FM also sells these...

I had a few extra parts laying around for boost controllers and added the remaining parts needed along with some bolts on my last mcmaster order. A .022" vent hole is drilled in the top (see pic). Drilling this hole with a hand drill is not fun and I have already broken several bits. As of right now they are untested, but given another few days I can test them on my miata. The two built before these worked fine so I see no reason these won't work great, too.

Bump. One is pending sale.

I strapped the two new controllers to my car and took them for a ride this evening. Both were tested at 8, 10, and 12 psi (w/ 6psi wastegate pressure). They hold boost to redline in 2, 3, and 4 along with holding boost in 5 and 6 (no redlining these gears on public roads....). Boost builds fast on my gt2554 with no overboosting and they work great. Of course, there's no guarantee your turbo setup is as sweet as mine.

Attachment 199137

Looks like they are both pending sale.

Nice little array of boost controllers there. :)