I'm not trying to be a twat here, but if your attitude on the net matches you in person, then I wouldn't call you back either.
Lets face it, you have a tiny turbo on a 2.5L engine to maintain stock response, I would buy one knowing that its not going to be able to pump 25psi at 7000rpm
You can blame the tuner all you want, but they are not the issue, it will be something you have chosen to do to the car, it might very well be the turbo, or it might be the exhaust you bought or the cat is blocked.
As a perfect example, I had my car on a dyno for a touch up tune, after running 20psi for 12 months with no issues we couldnt go over 13psi on the dyno due to a missfire and overheating.
Did I go blame the tuner because of something that was my responsibility? No!
With new turbo setups I always prepare to have te car tuned twice, 1st time to run it up and find issues, 2nd time to finalize the tune after any issues are sorted
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