i did the stinger drill mod on my jato and have to say that it has made a difference on how it runs and performs.
mine has the factory blue resonator pipe and i have drilled out the stinger to 7/32" decreasing the exhaust back pressure so it lets things flow a little better and it has made a noticeable difference to the acceleration in the low to mid range and a definite change to the sound... a little louder due to higher RPM
no need for me to buy a different tuned pipe for not
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