[kismetcapitan]

horsepower curves and torque curves are all familiar stuff, but what about boost curves? With stock turbos, are you supposed to hit a boost limit at a certain rpm (say, 4000) and then the boost stays locked in at that level until redline? My turbos seem to be kicking in ever so slightly late, and continue to build boost linearly to .85 bar at 8000rpm.

Pretty sure that my new Apexi Boost solenoid must have been plumbed wrong. With stock turbos(stock intakes, cams, big exhaust), at what rpm can 1 bar of boost be attained? I tried, on a lark, just switching the two tubes. No difference, although the question is always, will I break something??

The Apexi unit is supposed to be plumbed simply - one end to a vacuum source from the intake, the other end directly to the wastegate actuators. So far as I can see, mine was just plumbed into the stock maze of plumbing. Instead of rerouting everything, would it be possible to just seal off a portion? I really would like to have precise and direct control of my turbos, and have 1 bar full boost come in nice and early

 

[rKaida]

horsepower curves and torque curves are all familiar stuff, but what about boost curves? With stock turbos, are you supposed to hit a boost limit at a certain rpm (say, 4000) and then the boost stays locked in at that level until redline? My turbos seem to be kicking in ever so slightly late, and continue to build boost linearly to .85 bar at 8000rpm.

Pretty sure that my new Apexi Boost solenoid must have been plumbed wrong. With stock turbos(stock intakes, cams, big exhaust), at what rpm can 1 bar of boost be attained? I tried, on a lark, just switching the two tubes. No difference, although the question is always, will I break something??

The Apexi unit is supposed to be plumbed simply - one end to a vacuum source from the intake, the other end directly to the wastegate actuators. So far as I can see, mine was just plumbed into the stock maze of plumbing. Instead of rerouting everything, would it be possible to just seal off a portion? I really would like to have precise and direct control of my turbos, and have 1 bar full boost come in nice and early

Hey man,

"With stock turbo’s, are you supposed" - its irrelevant, you can show she engine boost, with what ever you want, trubs, s.charger. Manual and EBC controlled setups cause totally different ramp rates for boost anyways.
People sometime map diff boost, for diff gears.
If what your saying, is u set a boost level with your EBC, and it still raises a little up top? Usually if the controller has a lack of ability to control boost, it’s the wastegate not able to pass enough gas. But you say you have an exhaust? Have you got AM dump pipes?

“Boost solenoid must have been plumbed wrong” – maybe, check your manual man. Yah course you could hear GOOD advice here, then go and f*k up, make a mistake and overboost your turbo’s, don’t ask stupid questions like that. Check your manual, make up some new vacuum lines, For $10 peace of mind.

If your only running a bar of boost.. wont the stock GTR run a bar with the brass restrictor taken outa the boost line?