stock setup boost questions

[Flip90gsx]

I put a used turbo with a little side to side shaft play on a couple weeks ago since the other was seized. I noticed that when I go wot the boost isn't very smooth so i'm sure I have a boost leak and am getting ready to head out and pick up supplies to build one. But what suprised me is that it is boosting to 12 psi and as far as I can tell it is stock. I bought it tore down with a snapped timing belt and the turbo was seized when I got it running so I'm not sure what it was boosting at when I bought it. What would cause this? It hasn't went over 12 psi yet so i'm not too worried about that as much as what could be causing it and potentially causing future damage. WGA spring worn out?

 

[kanusky1990]

is it a t25? thats pretty close to what the stock psi is.... 10-12 psi sounds fine to me...

 

[xxNocturnalxx]

Most likely a boost leak related to the w/g. could be a bent w/g arm or spring issue like you said. 12psi. is nothing to worry about though a boost leak is. Start with a boost leak test then swap wastegates.

 

[Flip90gsx]

Sounds good. The 12 lbs doesn't bother me, just didn't want it to get worse and exceed the stock setup capabilities and cause further problems. The guy I bought the turbo off sent the wg w/ the turbo so I just went ahead and put that one on instead of putting mine on. Thanks for the input.

 

[BurrowZ]

is it a t25? thats pretty close to what the stock psi is.... 10-12 psi sounds fine to me...

His car says 90 GSX, which would be a 14b.

 

[xxNocturnalxx]

Yes, so 8 would be your normal psi. So did the w/g swap work?

 

[Flip90gsx]

It's cold and been raining the last few days so I havn't done it. I'll probably leave it be since I'm throwing a new exhaust w/ a 2g manifold and external wastegate on within the next 2 months. Have some other issues driving me nuts that are taking priority for now.

Thanks for your input everyone.

 

[potHead4sur]

It's cold and been raining the last few days so I havn't done it. I'll probably leave it be since I'm throwing a new exhaust w/ a 2g manifold and external wastegate on within the next 2 months. Have some other issues driving me nuts that are taking priority for now.

 

[Josh1001]

Check for boost leaks.And make sure the wastegate is not stuck or jammed and it actually opens I have a 90 GSX and I would barely make boost turned out to be the wastegate was rusted shut.

 

[1badpurple]

Have you checked the valves yet? If not I would do a leakdown test. These motors are interference, so if it snapped a t-belt its a good chance it happened.

 

[Flip90gsx]

Have you checked the valves yet? If not I would do a leakdown test. These motors are interference, so if it snapped a t-belt its a good chance it happened.

I put a new head and timing belt on but screwed up the tensioner and it ended up jumping a tooth or two. Hope I didn't bend a couple valves. I don't have the stuff to do a leak down test but I can do a compression test. Another thing is that I can hear the turbo spool. Is that a normal thing on a stock setup?

 

[1badpurple]

If it jumped a couple of teeth then most likely you would have bent some valves. The only way to check on car is to do a leakdown test. Sometimes it can be noticed through a boost leak test as well.