6 bolt swap=slow spool up

[DSM_GSX4life]

I just got my car back from the shop from a 7 bolt to a 6bolt. Before my engine swap I was running about 15 psi. Now I can even get the turbo up to 15 psi without red lineing in 1st and 2nd gear. In 3rd it gets to about 15 by 6.5k. Is there something wrong. cuz before the psi would level off at 15 psi for a while????

 

[superflyjmysnk]

Sounds like a boost leak somewhere to me, check all your ic piping and bov, if you have a leak tester its a good way to find the leak. They are pretty easy to make and work very well(air pump, valve stem, 2" plumbing coupler and 1 endcap) just bolt to the turbo air inlet and pressurize your intake to <20psi and you will hear hissing where your leaking boost

 

[spoolints04]

Sounds like the actuator rod came off the waste-gate arm. So the waste-gate is just open all the time.

 

[DSM_GSX4life]

Yea I am not quite sure. When i pinch the hose that goes from boost controler to the BOV the noise stops. The o rings on the boost controler might be bad b/c I can feel the air excaping from the MBC. Maybe my MBC is bad????

 

[superflyjmysnk]

When you pressurize the intake the mbc will always make a little noise and start bleeding off boost (thats how it manipulates the wastegate by reducing the boost the wg sees). You have a big leak somewhere or your wg is stuck open like the guy above says.

 

[DSM_GSX4life]

ok if it is my wg how would I fix that?

 

[superflyjmysnk]

check the wastegate actuator lever to see that it's still attached at both ends. I'm not sure how to check to see that the wg is stuck open besides dropping the turbo and physically checking it. I'm sure someone on here does though.

 

[DSM_GSX4life]

ok... I will try that. If any one knows another way please post it. Thanks

 

[myblack98gst]

are you using the same turbo before and after the swap, if so what kind?

is it getting any boost at all and then creeping to 15 or is it slowly creeping to 15..

if you have a datalogger check the timing.. if the cams are WAY out of spec then it probably won't build boost too good.

 

[superflyjmysnk]

Just thought of something else, if you replaced the turbo with the one that came on the 6 bolt it might be bad, you can check the intake impeller by popping off the intake at the turbo and check for shaft play and bent fins if its a different turbo than you were using. Just out of curiousity how much did you pay for the engine and the swap? ( my 7 bolt is starting to make ticking noises and i think i know where thats leading).

 

[DSM_GSX4life]

Well it is the same turbo. All we did was replace the block. All the manifolds and stuff is the same. I looked at the turbo while it was off and the fins were a little chewed up but there was no shaft play at all. And the turbo was fine before I swaped the engine. But I am planning on getting my big16g fixed soon any way. soo if its gonna cost $ to fix the spool up then i will just deal with it. I paid 1200 for the block. And the install was done my me my dad and our mechanic friend for free.