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Hey guys i have a 260rs stagea and i just took the boost restrictor out of the hose going into the solenoid and it wont go past the standard level untill very late in the rev range (if at all) like about 5.5-6k and its still not getting near full boost. it has always made stock boost max boost but with a very heavy right foot. It should be making 1 bar at around 4k rpm shouldnt it???, I have always though it was a little lazy in how fast it made boost, but this is showing me there is something not right. I know the std boost gauge is not very accurate but it should still show when full boost 14psi, hit 7 on the gauge. I have an after market boost gauge on its way and should be in by the end of the week. Car is stock except for an after market front pipe, stock cat back exhaust. Car runs fine idle is smooth and will rev without a missing.

Would the stock exhaust stop it from making boost??

collapsed muffler??

Any suggestions

Even if it were leaning out it should still be boosting???

i am getting a cat back exhaust soon and then a dyno run to check its all good.

Edited by cefiro
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Sounds like a blocked exhaust. maybe take the exhaust off from the cat back just to test it. or see if your mufflers and like theres anything loose in them. Also check the inside of the cat isnt melted or blocked.

I had a look around and tightened up hoses etc, didn't find much but now I am worried about having blown the rear turbo. I can see oil around the output side around the piping leading to the intercooler. I have posted pics. I took off the intercooler piping leading to the intercooler and there wasn't much oil only a light coating. The car doesnt seem to be burning excess oil. Runs fine.

answers????

post-7417-1205142620_thumb.jpg

Hey guys i have a 260rs stagea and i just took the boost restrictor out of the hose going into the solenoid and it wont go past the standard level untill very late in the rev range (if at all) like about 5.5-6k and its still not getting near full boost. it has always made stock boost max boost but with a very heavy right foot. It should be making 1 bar at around 4k rpm shouldnt it???, I have always though it was a little lazy in how fast it made boost, but this is showing me there is something not right. I know the std boost gauge is not very accurate but it should still show when full boost 14psi, hit 7 on the gauge. I have an after market boost gauge on its way and should be in by the end of the week. Car is stock except for an after market front pipe, stock cat back exhaust. Car runs fine idle is smooth and will rev without a missing.

Would the stock exhaust stop it from making boost??

collapsed muffler??

Any suggestions

Even if it were leaning out it should still be boosting???

i am getting a cat back exhaust soon and then a dyno run to check its all good.

The stock 3 centre gauges? If so, 7 on there is NOT 7psi :D

I reckon get it dyno'd and you'll see whats going on with it :D

well I dont think its the wastegates they both look to be fully closed at which mean that they must be closed, maybe blocked exhaust. come on I need some more help with this.

I also removed and blocked the boost solenoid line and it wont boost above stock, untill once agian very late in the rev range. What I did was block off the exit line to the soleniod and that hould have run unlimited boost yeah???? well tried it just to see if I could get it past the stock level and wont do it. But I didnt want to boot it too hard as It may damage the engine. Any more thoughts?????

when we pullled out the restrictor in a friends 33 GTR, @ first it dropped down to stock boost levels (5mmHG), was previously running ~6mmHG. Then turned car off and started again and was running @ 7mmHG. So try disconnecting the battery to reset the ecu. Hope it works out for you.

You may have a blocked line somewhere, have you checked all your vacuum/pressure lines from the solenoid to the wastegate actuators? I had a problem with my 32 GTR but I had a leak so the turbos were overboosting due to not seeing much pressure - yours may be the opposite. Another thing to check is your intercooler hoses attached to the cooler - make sure they're tight as.

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