ok i bought a ihi from a 87 thunderbird and the internal wastegate is set at 12 psi that is a little more than i am
wanting. i heard with a boost controler you can only raise the pressure not drop it. so what do i need to do to drop it to about 5-6 ish

can i just use the stock wastegate off the probe ihi's ??

 

6 psi?

might as well just get a cold air

 

haha very funny how about sombody with answers to my question.......



one more thing i did not know that a cold air intake added as much hp as 6 psi... but thanks for the info... or somthing......

 

Bend the wastegate "bowl" towards the hot side of the turbo while it's mounted. See if you can bend the mouts on it so that the bowl is just slightly closer than it was. Then go test it.

If that doesn't work, than tell everyone on the internet I don't have good idea's on Saturday nights.

 

Wait, I just thought of some more.


Drill a hole in your coupler, then test it. If you need more holes, git r done.

or

Take a 1" piece of pipe and weld it to the back of your gas pedal. Since you won't be able to open the throttle 100%, you should get right around 6psi, and if you get lower than that, you can now get a boost controller.

 

I lowered my IHI turbo wastegate by putting washers or shims where the wastegate actuator bolted on the compressor housing. The washer will make the actuator arm pushed in and make the flapper open earlier. I've tested it and lowered the boost from 8-9 psi to 5-6 psi. Check pic...

 

---- man you guys over complicate things.
If the WG is open too early. Hook up a spring between the wg and a fixed point on the turbo so that there is more presure keeping the wg closed. Using this method we where able to tune a WG from 4 psi to 8 psi.
If you want to drop the PSI like from 12 to 6 just put the spring in the other direction.
Guess this musta been discused a gazalion times and the guys are pulling your chain for not making the effort to search.