14b Creep Problems

[pecka]

Well this past week I installed a 14b on my 2g. Prior to the 14b I had no problems controlling boost on the t25. I could old 15psi rock steady. I ported the intake side of the 14b for better flow to the wastegate and also ported the o2 housing. The problem now is I can't hold boost below 15 or even 15 for that matter. I dont understand why with the t25 I could hold, but not the 14b. I have checked for boost leaks and there arent any that I can find, car holds 20 psi for awile. I have even tried running the pressure source for the mbc from the j pipe, helped some, but not all the way. My boost controller is fine because I unhooked it and ran straight wastegate actuator and it still creeped. I need to figure this out creep is killing me. I have a 1g bov, uicp, 3" downpipe and catback, and an sls (ball and spring type mbc). And yes I have an aftermarket boost gauge. Do you have any suggestions?

 

[underradar92]

I was running straight (no boost controller) with an adjustable actuator for a while & was seeing all sorts of weird boost patterns. It always found a way to creep too. So I tried running without the actuator arm on the wastegate at all & it would only see about 5 psi. Then I loosened up the tension on the actuator & put in a mbc & with a little adjusting I got her to hold 15 psi (then she starts to drop near redline but that is another thing altogether) Running w/o the actuator tells you if your wastegate porting etc. is effective or not.

 

[kenamond]

First, take the actuator arm off of the flapper lever, and see if you can open the flapper by hand. The flapper door could be hitting the O2 housing internally, or maybe it's hitting inside the downwind side of the wastegate passage in the turbine housing.

If this opens fine, do a test run like underradar92 suggested. You should get a few psi boost max with a well ported wastegate passage, because there's nothing holding the wastegate closed. If you still see creep it looks like your port job wasn't enough. You know the wastegate will open freely if disconnected from the solenoid, and you saw creep with the actuator arm off.

If you didn't see creep in that test, and the wastegate flapper opened easily with the actuator arm disconnected, then see if the actuator arm is interfering with something.

Another test is to hook a vaccuum tester straight off the actuator solenoid nipple, pump it up to the actuation pressure for that solenoid (don't know on a 14b) and see if the flapper lever turns enough. Some say you want 90 degree rotation of the flapper arm, but others say they only see 30 degrees or something. I bet it all depends on the type of solenoid. If it doesn't open the flapper enough (or at all), and you don't see the arm interfering with anything, your solenoid is probably bad.

 

[pecka]

ok, i will check how much it boosts with the vacuum line disconnected, the flapper opens fine, and the waste gaste actuator is functioning

 

[underradar92]

ok, i will check how much it boosts with the vacuum line disconnected, the flapper opens fine, and the waste gaste actuator is functioning

Careful with that, no vacuum line may lead to runaway boost. vvvvvv Cool, keep us posted

 

[pecka]

Careful with that, no vacuum line may lead to runaway boost.

Oh ok, I misunderstood what you said the first time, i will run with the actuator disconnected and see

 

[underradar92]

Oh ok, I misunderstood what you said the first time, i will run with the actuator disconnected and see

Cool. Sweet wheels BTW.