Maybe some highflow cats or artpipes , if you going to boost get a vortech decent price used and easy to install. On stock pulley with bolt ons Ive beat modded evo's stangs, camaro ss, 2013 sti stage 2 also stock 5.0's . Or go the easy way get a tune,100shot and step colder plugs and you'll beat you friends

 

^^ I looked into spray for months. If you wanna try it, it's not as dangerous as you think. You just need to do some reading. After my readings, zex is the best for our cars, you'll need a window switch and a wot switch, bottle warmer.... The list is long. But it can be done safely.

 

Spray is for bitches. What you need is a flux capacitor. Here's how it works:
http://www.streetfire.net/video/turbo-of-the-future-funny-****-stuff-vtec-dohc_50310.htm

 

When I go from driving my daily driver Toyota to the z. The z feels like a rocket but after driving the z for a while it feels slow. It's all about perception.

 

05 6.0 GTO= LS2= 400HP AND 400TQ VS your 280HP and 270TQ. with your mods and no tune lets guess on the high end and say youre at 300hp and 280 TQ...
So the GTO has 100 more hp and 100 more torque...thats a huge difference.

07 Mustang GT= 4.6L V8= 300 HP and 320TQ. Depending on how much boost he's running, you're at least 100HP and 100TQ behind him too.

06 STI: 300 (iirc) HP and 290 (iirc) Torque (If stock). same #'s as your car, but AWD for the launch. Same for the Evo.


TL: DR

Your car is not in the same horsepower range as these guys. If you want to keep up, you're going to need either a bottle or a snail. A tune would help though

 

I didn't realize the GT was supercharged. OP you need a turbo.

 

Long overdue update. My buddy just dropped a 5.6L built shelby motor with a kembell (i think that's the brand) supercharger on it. We don't even try against him now....
Also the evo got totalled. A Hummer rear ended him. It stood no chance....

Been looking into the art pipes and possibly high flow cats. In CA so high flows aren't legal, is there any way a cop can tell if you have them, or get a ticket for it?
I've also been looking at building some internals to eventually get a nice turbo setup going, but $$$ problems are going to make that a dream more than a reality.

Edit: Just got a text back from my buddy with the mustang. He's running 12lbs of boost, uses E85, and the engine has so many mods into it I'm not even going to list. HP: 812 TQ: 644
And yes.... he walks all of us.