boost creep with externam wg dumped

[TSITurbo95]

Ok so here's the story. I have a fp evo3 big16g. Ported the exhaust housing to match my ported stock 2g mani and he flapped a decent amount. It still crept. So i got an 38mm external wg flange on my 2g mani. I got this wg off a friend that help 18psi fine on a small 16g. It still creeps in different gears on my car. And yes my internal wg is welded shut. Any suggestions?

 

[kimcheefists]

Where is you're external wastegate mounted?

Edit: Nevermind I saw that you wrote that it's on your manifold.

Is the vacuum hose that goes to the wastegate in good condition? ie. cracks Also, where are you tapping for your boost source?

 

[jmorri15]

hey man sorry you couldnt make it out to the meet. its got to be a vacuum problem. no you could drop in a lighter spring to it and see how it responds. also are you running an electronic boost controller or mechanical? it could be the boost controller not allowing enough through.

 

[TSITurbo95]

The hose is new and the boost source is tapped from he j pipe. I do have a manual boost controlled as well. Ill try just the wg and see.

 

[LiquidX]

You have the vacuum line running to the correct port on the wastegate? How consistent are the creeping numbers, I'm just wondering if when you bought the WG the wrong springs were installed hence your "creep" if that's the issue. If you checked your springs then go back to vacuum issue.

 

[TSITurbo95]

There is only one vacuum port on the wg. I just removed the nbc so ill update back

 

[LiquidX]

What wastegate is this btw?

 

[jmorri15]

i think he said it was one that had been on a car with a small 16 set to 18psi. so it should be at least able to run that again. if everything else is set up right

 

[99gst_racer]

Remove the MBC from the equation and let us know what it does. Also, it's helpful to know exactly which spring or springs are inside the gate.

 

[TSITurbo95]

Ok so I removed the mbc and it works. But when my rpms get around 4k my boost gauge jumps but stays around 14psi. Idk what springs are inside.

 

[jen_cairo]

Your spring is ###### a 14psi rate spring. What kind of WG do you have?

 

[TSITurbo95]

Its an offbrand but i can verify it does work well esp when on my friends car. It seems to work well now that I removed the mbc.

 

[LiquidX]

If its working now then you isolated you problem. Was the MBC on backwards or just bad in general?

 

[TSITurbo95]

Never tried swithing the lines, just removed it. I was having issues with it before so i just chucked it and bought a new one. Thanks for the help.