Re: engine mods
First get a tuner, something like a Diablo Predator or Trinity programmer. Ur gonna need it once you do the mods.
Besides that, I recommend a cam and some performance heads. About 2.7k total before installation. Try getting a hold of Stu over at Inertia Motorsports he can set you up with a great package and deal if you order all at once, it's where I just got mine from.
He'll probably recommend the spartan plus cam, which is not yet on their website, and from what he says will add about 45-50 to the rear. As for their performance heads when installed in conjunction with the cam, you will get anywhere from 75+ to rear.(Just my estimate)
(06' Black JGC Limited with FULL SRT8 Body Kit, SRT8 Roof Rails and Mopar Spoiler, Mopar Front Bumper Grill Badge, Hemi345 BADGE, Diablo Trinity Programmer W/91 Performance Tune from ST Motorsports,SheraDon Stage 3 Performance Transmission + 2800 Stall, Inertia Performance Heads, Inertia Spartan Plus Cam, Srt8 Headers/Exhasut Manifolds, Full SRT8 Corsa Exhaust System W/ Reso Delete, Brian Quick 5" tips, 20% UD Pulley, 85mm Ported TB, K&N 77 Series CAI, Jet Flow 180* T-Stat, Billet Catch Can, 22 Inch Flat Black Factory Reproduction SRT 8 Replicas, Eibach Lowering Springs, Power Stop Rotors, Painted Red Calipers, Bosh Iridium Plugs, Shorty Billet Antennae, Limo Tint All Around with Mopar Matte Black Front Window Decal) and Jeep Black Ops Paramedic Hood
Diablo Trinity Tuner(Best 1/4 13.29 @ 103mph,-Best 1/8 8.45 @ 84mph -Best 0-60 4.79sec