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Discussion Starter · #1 ·
Please help. I have tried two different wastegates with promises of low spring rates and I still hit fuel cut. The good thing is my afm readings are 10.2-3. Im running a 61 trim with the stock 440s. I have checked my vaccum to the wastegate and the psi's match the boost levels. What else could cause overboosting?? Could a slipping clutch or bad v band or heat sleave insert for the wastegate cause this?? Please throw me a bone on what to check.:)
 

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Discussion Starter · #3 · (Edited)
Ok, let me clear this up. I dont want to hit boost cut. Im trying to get to the ideal spring rate. The first wastegate i used was supposed to be 7 pound spring. The second one i used was supposed to be 12 pound spring. Both LEAD ME TO OVER 14 POUNDS. Im having a boost problem. The fuel cut is saving my motor.
 

· HMOOB VWJ NYOB MINNESOTA
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your wastegate pipe is too small. Redo the wastegate pipe by cutting the old pipe off. Drilled/Port the wastegate hole/port to about 50mm. Put a 60mm wastegate(ebay) on their and you will not have this issue again.
 

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Discussion Starter · #6 · (Edited)
your wastegate pipe is too small. Redo the wastegate pipe by cutting the old pipe off. Drilled/Port the wastegate hole/port to about 50mm. Put a 60mm wastegate(ebay) on their and you will not have this issue again.
Yeah, somebody else mentioned it to me to take the turbo off and inspect the oriface of the inside. the guy who sold me the typical 2jz header off of ebay had no problems with over boosting and lent me his true TiAL 44 mm that is set off of 12 pounds. He showed me 12 pounds after I was done testing his wastegate. I have no boost controller running straight from the turbo which i checked at both the turbo side and wg side for psi's are matching the boost. Maybe its off by a little bit and just cant check if for im hitting fuel cut with his tial and the oriface is wacked. My boost gauge cant be off by much, its hitting fuel cut at around 14 and 15 so i cant say anything about that there. The other one I had problems with was the 44mm Xo2 from driftmotion set at 7 pounds supposively. Alot of ppl said they havnt had problems with this wastegate and you can use TiAL springs.
 

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hmm. you might have a vacum leak off one of the hoses. thats the only thing that would make the waste go higher than 12psi. try replacing the vacum hose from the wastegate. im not sure how you have it hooked up, but when your running the wg spring only your supossed to use the lower port of the wg and not the top port.
 

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Discussion Starter · #8 ·
Yeah..... like i said, the psi levels are the same from the turbo end to the wastegate end eg; i put an additional boost gauge right after the turbo fitting to the wastgate and did it also before the wastegate to validate the hose and the psis comming from the turbo, and it matches the boost im putting out.
 

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Discussion Starter · #13 ·
car idles well at around 650, i took the exahust manifold off today, it slightly bent due to the previous owner had different mounts thus he bent it...and there are dingle berrys inside, maybe that might cause a few pounds to go over on a good wastegate. Oh well, keep you guys posted as i go get some welding done.
 
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