My mechanic said today that I'd be around 300, and he typically doesn't bull**** me. I don't see how a H/C/I upgrade and full exhaust along with the little extras is gonna fall short of 300 rwhp.
Your setup is very similar to the 93 Cobra if i'm not mistaken. They were rated at 245 at the flywheel, and they were underrated, so lets say 230-250 at the wheels, plus your exhaust and other little bolt ons, maybe 270ish at the wheels. 300 rear wheel horsepower is about 380 at the flywheel. I think you will need a little more than your setup to see 300 at the wheels.
I'm not trying to be a prick here, but I think you are overestimating this. But, there are only two ways to know, run it or dyno it. So we'll have to wait and see.
I hope the upgrades make a huge difference. It really all comes down to how much fun it is to drive, and I'm sure you're gonna love it.
btw- Who is your mechanic? I had work done in Taunton at Leonard's and let's just say I didn't have very good luck.
Look at my sig. i'm not at 300 RWHP, i'm close but I don't think that i'm at or over it. I also ran 13.5 at 105 at Epping, NH (was my first time there, and I spun through first and halfway through second). Think that you may be going over board with the injectors and MAF. Also, the fuel pump is alittle much for that combo. You will totally have fun, but don't be disappointed when the dyno says differently. I'm sorry and don't want to be mean.
I plan on eventually going S/C, so while I can get the injectors and stuff for cheap, I am doing it. My mechanic works out of Westport, MA. He's the manager at Thad's Auto Salvage, and he gets to use all the garage equipment to work on my car with me, and I get alot of parts for cheap through him.