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boost guage

ImPrOvIsE

By ImPrOvIsE,
in Western Australia

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adam 32 Grand Master

adam 32

Posted
Posted

i still think despite the age of your car, if the actuator line is in good condition and is getting an accurate pressure reading then boost pressure will always be constant

zanda no i wouldnt stress. youve always got the boost cut at around 12psi (i think) which would prevent and mecanical damage

  • 2 weeks later...
caminperth Grand Master

caminperth

Posted
Posted

hmm.. Suprising because of the mechanical nature of the actuator.

It is my understanding that the mechanical actuator measures the boost level on the compressor side of the turbo and when this level gets to a certain pre-determined point (ie 6 to 7psi for an R33) it then "actuates" or opens the wastegate to keep the boost at that level.

If this is correct, then I fail to see how making the flow in and out (inlet and exhaust) of the turbo will in any way change how this mechanical actuator works. It will still open the wastegate as soon as it sees the set boost level.

The only way I can think that it could possibly produce more boost is if the increase in flow through the turbo is greater than what the wastegate can deal with. Therefore the wastegate is at maximum flow and still more air is flowing due to the increase in size/flow of the inlet and exhaust (predominately the exhaust), producing more boost.

I did not think that the maximum wastegate flow would be so low as to let this happen. I was obviously wrong. Hence I find it suprising.

Always good to find out new stuff. :rolleyes:

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