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Fitted new turbo - not boosting properly

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Ok i just fitted a KKR330 onto my CA silvia. I completely f**ked off the standard boost solenoid, like unplugged it and disconnected all vacuum lines to it. Now when i am boosting heaps and it hits around 1 bar of boost maybe a bit earlier it feels like you hit a wall. It feels like something is cutting out, its just got me a bit stumped because it only happens sometimes but most of the time in 3rd and sometime in 2nd.

 

The car has a stock ecu, stock injectors and stock fuel pump so i had the thought that it might be maxing out the injectors? Although otomoto say that the turbos actuator holds 11psi standard so i thought bolting on the turbo running standard boost would be ok because it doesnt really matter where 11psi is coming from as that is what my standard turbo was running and i never faced this problem.

 

Has anyone experienced this and has any solutions?

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Your new turbo will flow alot more air at 11psi than your old one so your hitting boost cut. Basically when the airflow reaches a certain amount the stock ECU will cut fuel + ignition.

 

You can remap the ecu to get rid of it.

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Agreed, the boost cut is being hit... a remap will fix the issue and I would get it tuned to suit the new turbo...

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but the computer is taking the reading from the boost solenoid which is now sitting in my shed so shouldnt it now have no boost cut?

 

How do you think i should combat this? besides remapping right now, boost tap and turn it right down?

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but the computer is taking the reading from the boost solenoid which is now sitting in my shed so shouldnt it now have no boost cut?

 

How do you think i should combat this? besides remapping right now, boost tap and turn it right down?

 

Is it like back firing etc when u hit it? Sounds like u need an uprated fuel pump in it sounds like its leaning out hard.

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but the computer is taking the reading from the boost solenoid which is now sitting in my shed so shouldnt it now have no boost cut?

 

How do you think i should combat this? besides remapping right now, boost tap and turn it right down?

 

Its calculating the amount of boost / power from the amount of air being sucked in the intake. If you are hitting a boost cut then you must do some form of aftermarket ECU or remap to solve the problem.

 

Also a boost controller is not going to help you as it sounds as through you are running stock wastegate pressure. A boost controller can only allow you to run more than stock pressure not less.

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but the computer is taking the reading from the boost solenoid which is now sitting in my shed so shouldnt it now have no boost cut?

 

How do you think i should combat this? besides remapping right now, boost tap and turn it right down?

 

Is it like back firing etc when u hit it? Sounds like u need an uprated fuel pump in it sounds like its leaning out hard.

 

Nah its not really back firing it just feels like fuel or ignition is being cut and just like hits an invisible wall.

 

but the computer is taking the reading from the boost solenoid which is now sitting in my shed so shouldnt it now have no boost cut?

 

How do you think i should combat this? besides remapping right now, boost tap and turn it right down?

 

Its calculating the amount of boost / power from the amount of air being sucked in the intake. If you are hitting a boost cut then you must do some form of aftermarket ECU or remap to solve the problem.

 

Also a boost controller is not going to help you as it sounds as through you are running stock wastegate pressure. A boost controller can only allow you to run more than stock pressure not less.

 

Yeah fair enough well i guess a new computer is the next thing to do then.

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yep the boost cut is in the ECU,

the moment you run more then 12 psi it will hit a huge cut, does feel like ur hitting a wall

you need aftermarket ecu if you want to run more then that, if your running more then that on stock internals and stock ecu u should have a tune anyway

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Its boost cut caused by your standard comp and AFM..

You removing the solenoid doesnt do shit haha, it get the reading

from the AFM. so in theory if the turbo was big enough and could still come on boost

you could still get boost cut on 7psi..

setting it to 12 pounds or wateva wont help... a fuel pump will make it go harder when

its not cutting.. but will do nothing to stop it..

just get a z32 and gtr inj and Dr D remap and u'll be laughing

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lol i have no mods... i bolted on a big turbo and took off any boost controling devices then floored my car? whats wrong? :no:

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