*eurospeed951*

I think i finnaly have my boost controller hooked up right, and this what is going on now. the car will boost to the set boost then quickly drop back to around 8 psi. I have a used Deltaget. Think this is the weak link?

special tool

So how did you rectify the lbe? Are you controlling the Delta with it? I think you were getting some confused feedback in the other post from guys who weren't reading all the posts.
Your sig doesn't say what turbo you have - a worn 26/6 may naturally drop back to 7-8 pounds at redline because of its own limitations.
<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />

*eurospeed951*

No, i'm still useing the profec. 26/6, but this happens way before redline.

*eurospeed951*

Bump

*eurospeed951*

<img border="0" alt="[burnout]" title="" src="graemlins/burnout.gif" />

awilson40

sounds like a weak wastgate spring.

David Floyd

Hey Chris,

The Deltagate worked when I removed it from my car so I don't think that is the problem, but it is always a possibility.

I am sure you have checked for boost leaks around hoses?

Is the turbo in good shape? An original tired turbo may only hold 8 psi at redline.

tazman

Don't you have to flow a lot more air to generate 8 psi on a 2.8 liter compared to a stock motor?

Danno

How are you hooking up the Deltagate? It should only be used in single-port configuration with the LBE. The way this works is to have the top vacuum port open to the atmosphere. Then the control line from the LBE should plug into the side boost-port. If this is the way you have it hooked up, then we need to look at the wastegate itself.

"the car will boost to the set boost then quickly drop back to around 8 psi."

Konstantin had a similar problem last year. I think he resolved it by installing the stiffer spring and he may have even replaced the wastegate as well.

toddk911

Can a stiffer spring be used on stock wastegate or only aftermarket?

If so, how much difference from shimming?

Danno

Shimming typically raises the opening pressure (at the diaphragm nipple) from 3-4psi to around 5-6psi. This is good enough to cut the high-RPM boost-drop in half (13psi with 15psi max-boost instead of 10psi stock).

Our upcoming wastegate upgrade installs a stiffer spring to have wastegate opening start at around 13-14psi; significantly stronger than a shimmed one. This will allow a stock turbo to hold max-boost to redline. However, due to the extensive precision machining required, these wastegates are only available on an exchange/core basis.