I would be more prone to looking at 3.73's instead of the 4.10 especially if your doing any HWY driving. You'll get a very nice response from the switch of 3.27's to the 3.73's. The Pulley would help, as would porting the blower/intake. Cobra owners are seeing 30 rwhp from this procedure. Long tube headers will only net you about 3-5 rwhp but will add over 25 ft lbs of torque. Some some areas to look at. I would start with gears 1st.
I would be more prone to looking at 3.73's instead of the 4.10 especially if your doing any HWY driving. You'll get a very nice response from the switch of 3.27's to the 3.73's. The Pulley would help, as would porting the blower/intake. Cobra owners are seeing 30 rwhp from this procedure. Long tube headers will only net you about 3-5 rwhp but will add over 25 ft lbs of torque. Some some areas to look at. I would start with gears 1st.
NA, not really. You'll gain some but not nearly as much as the blower cars. 5.0 mag did a test on long tubes on the '03 corba about a yr back, it showed a gain of 2.7 rwhp but 22.3 rear wheel torque.
Dont know about your location as I'm on the West Coast, but chat around with other stangers in your local area for resources. No you wont need to upgrade your fuel pump with any pulley. As for porting, most any port/polish shop can do this. Might try posting your question about the porting on the SVT forums.
Before adding a smaller pulley, you might want to check the air/fuel ratio on a dyno to verify the tune and/or state of the fuel system. Some cars with stock pulleys and pumps run on the lean side in the upper RPM range. I don’t know what they would tell a person over the phone but on their web site, Chicane has recommended checking A/F when performing pulley swaps.