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Discussion Starter #1
I believe i read that the turbo boost on the motor is really more inline with how much throttle I use. So if I am at 6000 rpms but arent really on the throttle, more or less just riding the gear, there should be little or no boost because the throttle bodies arent open much, even though the boost gauge is says there is. Is this true?

With deceleration, can I still decel down the gears for the loud rumble like with a regular pipe since there is no throttle action. I still wanna come to red lights and be able to make the good ol' decel pops when i gear down. This shouldnt hurt the motor right?

Thank you in advance
 

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Color me Gone
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27,333 Posts
The boost gage takes it's reading above the throttle plates. Below the plates can be in vacuum while above can be in pressure in fact that is the way it is 99% of the time while your riding. You can take a vacuum gage and hook it to the right side below the throttle body you will find two ports with screws in them, get a fitting and hook in a vacuum gage and go for a ride, the two readings from the vacuum gage and the boost gage will only agree when you are under heavy or full throttle.

Yes you can decel as normal if you like the rumble of engine braking.
 

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The Hawk
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I used to run my boost gage from the vacuum port on the throttle body, below the throttle plates. I needed to know when the motor was on boost for tuning purposes more than I needed to know when the turbo was making boost. Max is correct, when under cruise conditions, the turbo will be making some boost but the engine will not be under boost because the throttle is only open about 7 to 10%. Seems the turbo provides enough back pressure on decel that you get a good rumble but no pop, at least mine was that way.

Mike
 

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Steve
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1,402 Posts
:them:
Max said:
The boost gage takes it's reading above the throttle plates. Below the plates can be in vacuum while above can be in pressure in fact that is the way it is 99% of the time while your riding. You can take a vacuum gage and hook it to the right side below the throttle body you will find two ports with screws in them, get a fitting and hook in a vacuum gage and go for a ride, the two readings from the vacuum gage and the boost gage will only agree when you are under heavy or full throttle.

Yes you can decel as normal if you like the rumble of engine braking.
 

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Discussion Starter #5
so could i just hook the boost guage up to the vacuum ports on the throttle body and get an accurate picture of how much boost the engine is getting instead of just how much boost the turbo is making?
 

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Color me Gone
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Shima said:
so could i just hook the boost guage up to the vacuum ports on the throttle body and get an accurate picture of how much boost the engine is getting instead of just how much boost the turbo is making?
Yes, if you hook below the throttle bodies then you will know how much boost you are using and not how much is being made. When below the throttle bodies the gauge reads 0 90% of the time and only moves during accel.
 
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