GEN 1 Roush TVS 72mm Pulley, only 6 psi

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ksutton

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Just installed a 72mm pulley and uploaded a JDM tune. Not seeing more than 6.5 psi on the gauge. Boost comes on harder but maxes out at the exact same mark as before. Any ideas?
 

1BAD454SS

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make sure your bypass valve on blower closing all the way. If it doesn't close all the way you will loose boost. It should be closed with engine not running . With engine on it should be open. Looks something like this in picture
 

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JimIII@JDM

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What belt are you running on the truck? Should be a gates K061247

Do you see 6.5 psi just stabbing the throttle quickly or at peak RPM. We'll see as much as 10 peak here at sea level. Usually it's 8 instantly and climbs as the RPM band goes up.

Headers and cat delete will lower boost figures, since your relieving back pressure...

What plugs and gap are you running?

JimIII
 

Tmaroule

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I am having exact same issue

2014 Roush raptor.. put a 72mm pulley and only getting 6-7 lbs

I have the ngk plugs that I was told were gapped to .030.


I was just talking about the bypass .. I will check that tomorrow.

My gauge isn't lazy either .. it goes right to it and stays there.
 

cobra51585

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I am having exact same issue

2014 Roush raptor.. put a 72mm pulley and only getting 6-7 lbs

I have the ngk plugs that I was told were gapped to .030.


I was just talking about the bypass .. I will check that tomorrow.

My gauge isn't lazy either .. it goes right to it and stays there.

Were you ever able to figure this out? I am only getting 7-7.5 at sea level with my 72mm pulley as well (800 ft elevation). Not sure if I have belt slippage or another issue. Runs strong but I want to make sure I am making proper boost.
 
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