Well some I have read reckon they pop. But I have the 2 in 2 big radius and a kurry corsair heavy breather and zero popping. I used tts to tune mine and I am only using on of the canned maps. No tune yet. Check your header bolts maybe loose and leaking.
Hi well it comes down to tuning ? I have been selling and fitting Thundermax's since 2006 and we can tune the Poping out with a Thundermax - but with SE Race Tuners and Power Commanders it some times is impossible because of there Limited Tune Abilty. HFS