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Discussion Starter · #1 ·
This question is mostly aimed at the guys out there that are performing tunes, especially Protunes. Do you guys replace the stock restrictor pill every time you do a Protune? Maybe you never replace the stock restrictor pill. Let me know what effects the pill has on tuning in your experience.
 

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On Stage 2 STIs with the stock VF39 and stock Boost solenoid, tuners do NOT replace the restrictor pill.

The only thing that might be considered 'replacing' is when tuners will rip out the stock BCS and replace it with a Prodrive, Perrin, or GM solenoid. These solenoids can be installed in interrupt mode and therefore require no restrictor at all.

t
 

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I had equal length headers at one point and for some reason my car wouldnt build boost with the stock pill. but before the headers i had a stock pill protuned and when i took the equal lenth headers off the boost went crazy. but i think that was just a bad design for the headers. i got more power and more torque with the stock headers and stock pill boosting to 21 psi on race gas.
 

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Discussion Starter · #4 ·
Thanks Wolf. My pill was definitely replaced during the Protune. The tuner said it was pretty standard practice. I flashed back temporarily to Stage 2 and still had overboost problems. I had no issues at all with overboost with the off the shelf stage 2 and the stock pill. I'm wondering if I should ask for the stocker back and try some pulls with it to see if the car still overboosts. The overboost on the highway in 5th and 6th is bad. It passes the 15,000 Pascal mark on the gauge by quite a bit. It's probably more like 17,000 Pascals, which is well over 22lbs of boost.
 
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