Boost Control Issues

[GTTR34 4 door]

I have had my rb25 with a gt3076 tuned yesterday and wanted to see if anyone knew why my boost would spike for 500 rpm then stay steady. Can't post dyno sheet. Basically 3000 rpm just hits 12 psi, 3500 rpm 16psi 4000 rpm till redline 12 psi. He looks to have taken a shortcut and used the intake manifold line to my actuator. Is this the cause? Also is 300hp good from 12psi?

[JonnoHR31]

what boost control are you using?

[GTTR34 4 door]

Gizzmo ibc, tuner uses em all the time...It's all set to just run the 12psi actuator

[JonnoHR31]

tried turning it off and running just off the actuator?

[GTTR34 4 door]

Yeah. Still spiked at same spot

[JKR-32]

could the actuator flap be fowling on the dump pipe or something.....?

Just go external gate problem solved......

[JonnoHR31]

exactly where is the boost source plumbed in and how long is the hose?

how much pre load is there on the actuator?

[blk94r33]

Think 666DAN talked about this in his DE+T thread?

The 34's have a 2 stage intake manifold (higher low rpm torque etc) that switches around the 3000rpm point? And caused similar problems with his car...

It's there somewhere:

http://www.skylinesaustralia.com/forums/tu...N-A-t33407.html

[GTTR34 4 door]

exactly where is the boost source plumbed in and how long is the hose?

how much pre load is there on the actuator?

its sourced after bov, hose is around 50cm im going to tap into the piping next to the turbo and see if that helps.