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1995 EZ30 Coupe
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470 Posts
...boost tapers down to 14-15 psi when it should be 18.5.
...i need the top end power.
Are you referencing the compressor housing for your wastegate boost signal? I know that's how the factory does it, and I assume they have a reason, but when I switched to the manifold for wastegate boost signal everything got better. Couple extra psi across the board was nice, and getting rid of boost taper was even better. The best thing was eliminating a hesitation when transitioning from vacuum to boost. It was jerky before, and silky smooth after. (Probably related to my home brew tune.)

This was with a manual boost controller on a td04, not maxed out or anything. It just tapered with the compressor reference, and didn't with the manifold reference. Might be worth a try.

Anybody know why they reference the compressor in stock form? I assume simply because turbos are often sold with a wastegate attached...
 

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I ❤ BOOBIES
99 Coupe
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16,993 Posts
Discussion Starter #7,085
Yes its referenced from the compressor but i need the boost taper and the failsafe of having an electronic solenoid. When its properly tuned it works fine
 

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I ❤ BOOBIES
99 Coupe
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16,993 Posts
Discussion Starter #7,089
Yeh i got the dr590 single channel, $106 on amazon. Works great, more reliable than the gopros for sure. The windshield was super dirty, but its a good camera and the night clarity is fantastic.
 

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Premium Member
2001 Subaru Impreza L coupe
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768 Posts
Yeh i went up to 85% WGDC in some areas and only got a .5-1psi change. Im going to add a bunch of preload and drop duty cycle to see if it helps. Its a twin scroll 16G with a 16psi spring in the gate.
Hmm, almost seems mechanical and not the tune.....maybe something with the actuator like you said a few posts up?

85% duty cycle seems like a lot for 18.5psi on a 16psi spring. For what it’s worth.....I have a 15psi spring with 20psi target and only need 27% WGDC. My old setup was 17psi spring and 20psi target and only needed like 25%.

Love the crosstrek color by the way. Really wish they offered that color for the BRZ or current gen crosstrek.
 

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I ❤ BOOBIES
99 Coupe
Joined
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16,993 Posts
Discussion Starter #7,091
Yeh the wastegate port size is way to big, i tightened preload up two full turns which made it hold boost longer through the RPM range after it reaches 18.5 peak, but now is dying off fast again after 5800-6k. The acutator is now cracking at 20psi.

And they did have the BRZ in hyper blue last year.
 
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