S/C V6 will produce similar numbers to a lightly modded V8. if you can find a cheap V6 car and spend the extra money on the blower and still be under the cost of the GT, then do it. if the cost is similar to the price if a GT, then get the GT. the GT comes with better suspension, dual exhaust, and (so I hear) more comfy seats.
if you are looking to upgrade a six to more power than a GT and want it to handle better than a stock GT, then it will cost you more money in the long run. this is especially true if you are talking about new car prices versus used prices. you can get a used 6 cylinder S197 for under $10k now. however, i have seen modded GTs go for about $14k.
the six has potential to be less investment for the GT. when you start adding in additional upgrades, the prices start to climb. it all depends on your expectations for the S/C'd six.
one member here took his sixxer to the 10 second club, but later swapped to a V8. the faster you go, the more custom part you will need to build a V6. off the shelf parts are not available for the V6 that are suitable for high horsepower applications.
If you are happy with about 300rwhp, and do not care about anything else, a supercharged V6 may be for you. if you want to upgrade to more power later, a GT may be better in the long run.
Before I bought my car I was considering getting a six and supercharging it later. I finally decided on the GT because I couldn't bring myself to buy a six cylinder muscle car (gotta love the sound of a V8). If you are looking to modify a car the GT has a stronger aftermarket also. The only upsides to a six that I found was that the six is cheaper from the get go and the insurance runs cheaper than a V8.
insurance premiums between a V6 and a GT are very similar. check into the pricing from your agent. i bet the difference is so minimal that it does not weigh into your decision.
If you want a 12 second car, or even a high 11 second car, the 4.0 six banger is fine with FI. If you want to go way beyond that, you are going to need some cash. I had a fully built setup and threw a rod. I had pistons, crank, heads, cams, fasteners, bearings, everything minus the rods. I had the stock forged rods. So budget some cash to get some rods...and good luck if you go with moronas rods, it takes him at least a year to do anything. The SSM rods are good, but they stretch over time, so that left me with custom rods costing 2-3k.
It's a stout motor, and can deliver power, but I wanted a 10 second car that can touch 9's when I want to. So I went with a 5.4 3v truck motor, and it was actually cheaper this route as I was able to use mod motor parts off the shelf. I got another 5.4 3v block, with forged internals going into the car late may early june. Then I can up the boost to 17psi.
If you go with a 4.0 V6, I would cut to the chase and go with a PH turbo.
If you want a 12 second car, or even a high 11 second car, the 4.0 six banger is fine with FI. If you want to go way beyond that, you are going to need some cash. I had a fully built setup and threw a rod. I had pistons, crank, heads, cams, fasteners, bearings, everything minus the rods. I had the stock forged rods. So budget some cash to get some rods...and good luck if you go with moronas rods, it takes him at least a year to do anything. The SSM rods are good, but they stretch over time, so that left me with custom rods costing 2-3k.
It's a stout motor, and can deliver power, but I wanted a 10 second car that can touch 9's when I want to. So I went with a 5.4 3v truck motor, and it was actually cheaper this route as I was able to use mod motor parts off the shelf. I got another 5.4 3v block, with forged internals going into the car late may early june. Then I can up the boost to 17psi.
If you go with a 4.0 V6, I would cut to the chase and go with a PH turbo.