I watched video on youtube where they actually did a lab test which should be accurate. You can skip the first 12 minutes and actually see the graph where they say engine actually has some advantage with RPM and generates more torque. It's very interesting, not sure if it's worth spending over 300 dollars though.
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By the way if anyone is intersted doing stage 1 with JB4, I've got a brand new one for sale and it's listed on the market place. I'm doing my stage 3 APR tune on Monday so won't need it. Can't wait to drive a powerful car again.
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