wastegate plumbing

**celicapain** · 12-02-2008, 02:03 PM

howdy happy toymodders
Ive got a HKS(copy) standard external wastegate and i just wanted to confirm that im plumbing up the pressure lines correctly. Ive currently got the pressure signal running into the top and bottom nipples at the same time, but this doesnt seem right to me, should i have the top chamber connected to manifold so when i get off the throttle it opens the wastegate or is it correct the way it is at the moment? enlightenment please .....

**Norbie** · 12-02-2008, 02:18 PM

That is incorrect. The way you have it now the wastegate will never open.

You use both inputs with certain types of boost controllers; the bottom one gets constant boost while the top one gets regulated boost. For a simple setup with a bleed valve or no boost control at all you just use the bottom input and leave the top one open.

**celicapain** · 12-02-2008, 02:28 PM

tre bon, thats how i had it set up when i was driving it. so, running a boost controller i would have the solonoid inline with the top nipple, venting to atmosphere with the bottom nipple hooked up to the compressor cover, farkin funktastic.bonerific. cheers norbes

**Talasas** · 12-02-2008, 02:32 PM

The pressure to open the wastegate comes from the compression housing of the turbo (direct boost) and like Norbie said, if you have a boost controller/bleed valve you attach that to the other pipe on the wastegate. Otherwise if you plan to use the stock pressure rating of the wastegate you would block the other one off.

**JustenGT8** · 12-02-2008, 02:42 PM

The bottom side allows the WG to ope under pressure and hence controls boost. in most cases this is all you need to connect.

The top port can be use to open the WG under certain vac conditions such as cruise which assists with economy, emissions, under bonnet temps.

as Norbie says the top port also gives extra control of the valve when using some types of boost controller.

In playing around with the ports i have never found any performance gains from using the top port.

**The Real Roadrunner** · 13-02-2008, 01:50 AM

i just run a line into the lower port and use a bleed valve/soleniod in that line.

you normally only use the top if you cant get the spring to hold the gate closed enough or as justin said it can be used to suck the gate open under cruise conditions (never bothered with it personally)

cheers
linden