I have $500 to spend for Christmas and I have narrowed it down to one of the following 3 options for the 2004.5 in my sig:

Cam (Helix or Hamilton)
Exhaust manifold (ATS or BD)
Arson III CP3 Kit

Eventually I will have all 3, but my goal is to eventually get to 600hp, so which do you guys think I would be the happiest with considering the mods I have at the moment?

 

how bout studs? (unless you are shooting for the 625 series.

 

Good suggestion, but don't get me started on the cost of head studs. How these companies get away with charging $500+ for a set of studs that probably cost less than $20 to make is beyond me. I simply cannot bring myself to pay that much for something so simple. From my perspective, it's not a justifiable purchase. I know I'm gonna get lectured for that remark, but that's the way I feel.

 

Well, actually the tool steel used for the studs is expensive to begin with. That said, the profit margin on any of the listed items is the same-- meaning usually 2-3x cost of manufacture.

None of the items listed, by themselves, is going to get you a whole lot. The cam would maybe be the biggest seat of the pants feel. It won't provide more peak HP, but will broaden the curve and give more flow and usually you'll feel more torque. Also, unless you are doing it yourself, cost of installation is usually $800-1000.

The arson just supports the fueling you want to give it... no bang for the buck immediately, but necessary down the road to support the things that do make a difference.

The manifold, like the cam, produces benefits that are hard to quantify, and by itself is hard to notice. Slightly better spool, maybe a tick lower egt or fuel mileage. Results vary widely.

 

Cam so you can get rid of the in cylinder egr. My 03 doesn't do as much of it at the 04.5 and i have no off idle touque. My 99 bone stock had better off idle touque and throttle response than my chipped 03.

 

I would do the cam...

I did cam, then turbo/manifold/studs.

 

Thanks for the input guys. I understand that none of them will make a huge difference, I just wanted to know which one y'all would do if you were in my shoes. And, yes, I will be installing the cam myself so the labor cost is not a concern.

 

Unless it's one of the monster cam's it will be fine with the stock turbo for a while.. it's a good way to start (aside from the studs you don't beleive in)