Boost not holding at max

EugeneR

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I have some queries on boost,is it normal that our boost cant hold it at max?because I when full throttle it,it goes up to 21psi and drop to 18-19psi.

 

AdamD19DFK8

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Boost lowers the higher you go in the Rev range. Are you untuned, plus was this with fairly cold ambient temperatures? When I was stock I believe peak boost was 23psi down in the low 4k range then tapered off to 18-20psi at redline. With hondata and my tune peak boost is 26.5psi down low and at the top it sits around 23.5-22.5 at redline.

What you're describing seems pretty normal. If it's cold at peak boost of 21 sounds about right, when it's real cold I'll only see 25psi, maybe 26
 
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EugeneR

EugeneR

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Boost lowers the higher you go in the Rev range. Are you untuned, plus was this with fairly cold ambient temperatures? When I was stock I believe peak boost was 23psi down in the low 4k range then tapered off to 18-20psi at redline. With hondata and my tune peak boost is 26.5psi down low and at the top it sits around 23.5-22.5 at redline.

What you're describing seems pretty normal. If it's cold at peak boost of 21 sounds about right, when it's real cold I'll only see 25psi, maybe 26
Yes..it around 40F,so which means my peak is 21psi and constantly drop to 18-19 is normal right?
 

AdamD19DFK8

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Yes..it around 40F,so which means my peak is 21psi and constantly drop to 18-19 is normal right?
Yes. When it's colder the air is more dense so the ECU will Target less boost. When it's hotter the ECU may Target more. On the oem turbo it peaks boost pressure down low and will taper off as RPM increases. 1st and second gear you will see less boost as well since the torque is dialed back to minimize wheelspin.
 

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Would you rather it be tuned to boost and hold 18 psi or be happy youre getting a midrange bump of a few psi extra?
 


fatherpain

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Is your car stock or modded? If upgraded any parts connected to your intake/vacuum system,
could have a small boost leak. Tested my system last week and found and fixed (3) leaks. Boost levels restored and high RPM idle and P0507 CEL fixed (so far)


I have some queries on boost,is it normal that our boost cant hold it at max?because I when full throttle it,it goes up to 21psi and drop to 18-19psi.
 
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EugeneR

EugeneR

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Is your car stock or modded? If upgraded any parts connected to your intake/vacuum system,
could have a small boost leak. Tested my system last week and found and fixed (3) leaks. Boost levels restored and high RPM idle and P0507 CEL fixed (so far)
I have no CEL and No leak was found..just that weather over here changes dramatically.
 

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I could be wrong but the amount of boost you're seeing at the higher rpms is based on the torque values being met by the factory calibration...as in the ecu is meeting the torque it is supposed to and doesn't need more boost...

 
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