You're going to need to pour a lot of money in to be able to compete with the V8's. Here's a list of things that people usually do, the prices vary and can get pretty high, but that's all up to you.
Definitely consult a speedshop who's done these mods to mustangs before. A combo of any of them can be overdone and cost you a bunch of money or blow the engine.
To change the gear ratio, you'll have to special order a new gearbox and/or transmission. They will have different ratios from OEM or aftermaket manufacturers. You shouldn't have any trouble finding parts. I'd recommend going with a 6-speed tranny if you can afford to have one put in.
To get the power up, you are right to increase the redline, that's just a racing 'chip' that any speed shop will have.
Along with that, you will NEED to put in a high performance exhaust manifold. Since you will need the extra airflow, just upgrade the whole system. Yes, upgrade the intake manifold as well with the cold-air intake.
I'm not sure how with the electronic systems, but upping the compression ration will give more torque, and the mustang engine can handle it.
Having the engine bored out will allow more power but lower your real redline, if you do this, make sure you do the chip mod afterward but you'll have to be more careful with the compression ratio because the walls are now thinner and more fuel is used. Too many gaskets and heads get blown because people bore out too far, but it's a HUGE torque boost.
Increase the throw, the stroke length, this gives each revolution more space for fuel on the top of the cycle and more compression on the bottom.
BIG ONE that is really cheap... Get a lighter flywheel and a lighter crank. It reduces the weight that the engine has to push in order to keep turning/rev up, making it more efficient. Therefore; more HP
But most of all, make sure the mech you go to is competent. If they've never done these mods on a Stang before, at least make sure they know what they're doing.
Alright, so my goal for this summer is to have my V6 5-speed manual transmission 2000 Mustang able to compete and hopefully beat a stock '99-'04 Mustang GT.
I've already started with minor upgrades like a cool air intake and high-flow air filter. I've also replaced the stock hood and side scoops with real scoops (the stock scoops are filled in and do not actually do anything performance-wise).
Now for my next upgrade, I'm thinking of a cat-back exhaust system, because the rule of thumb seems to be to get good intake and exhaust systems before anything else. So my first question is: what kind of exhaust system should I get? And is cat-back sufficient for the amount of modding I want to do, or do I need to upgrade the whole exhaust system?
After this, I'd like to get a short-throw shift kit. But let me know if you think that there are other things I should get first or that are more important.
After this, I think the most important matter is to push back the "Redline" (for lack of a better term). Stock V6 Mustangs have the red line on the tachometer drawn at about 5600-5700 RPM. This *needs* to be quite a bit higher if I'm going to compete with V8 'stangs (I would hope for a 1000 RPM increase, but I would accept as little as 300-400). I assume that with this change, a modification to gear ratios would also be a good idea, since each gear now has a higher "range"? If so, how exactly do I go about changing gear ratios?
Then, it's all just about getting the most performance. So, if I still have money to spend after all of this, I was hoping to get a turbocharger. I've seen prices on turbos range from $200 for the turbo alone to $1400 for the turbo plus a plethora of parts whose function I didn't understand. So, how much money do you think is a good amount to plan to spend on a turbocharger, including labor (I'm assuming that's not something you can install yourself lol)?
Thanks a lot for any and all suggestions.

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