hey bud! unfortunately, modding a 3.1 will never net you too much power. unless you do an all out turbo build.
here are some sits that will help you. all i have on my 3.1 is an intake which i bought off ebay for 40 bucks.
check out Milzy Motorsports - American Muscle, Reborn
and also check out 60degreev6.com.
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