Well it kinda depends on what you want to spend and what effort.

Headers, high flow CAT, high flow muffler, mandrel bends on the pipe,
Cold air intake, K&N type filter and power programming of the computer
is the easy stuff.

Then you start getting into the engine, porting the heads and a cam area couple
of the easier options.

A blower is a really good bang for the buck if you don't want to tear into the engine.
Vortech or Paxton is a more/less bolt on a cetrifigal type blower. You would probably need a custom tune and maybe larger injectors. They could tell you for sure whats needed.

Regarding the torque converter, a looser converter will get you off the line faster. That is where you get the most torque multiplication and get you into the RPM power better. Probably won't help much at speed though and its a bunch of work. Definately not the first thing I'd go for. Do you're other mods first.

So we are coming full circle....what is your budget? Once you know that you can decide what makes sense.

 

im putting a new motor tomorrow its a remanufactured 4.3 vortec i kno ill have a lot more power than i do with my current motor im also going to put a high flow magnaflow cat and the super40 series flowmaster muffler i want to put a msd ignition system in not sure if itl b worth the money any1 have 1 will it give me more power and i hear itl improve milage but how much? also i want to put a cam in but hear that it can mess with my vacuum sm people tell me itl take a little n some say im gna lose all the vac to the brake booster. just wondering bout these things ..........

 

msd ignition will give you throttle response poertsch i got a supercharger and my blazer gets real horny lol

 

Oh wow so many Infos. I will see that i compare all the Threads here and see what i can do in the winter time on my Baby. The Problem is that you have to spend so much money. And in the moment my car is of Road because 1st it start the winter and i don't drive him in snow. 2st i have a problem with my ignition switch. my Blazer will not show me any light inside my dashboard. So i have to replace this first. Because no Volts from the ignition switch, no possibility to move my place. Gear is in park position.
But I try to get more work on motor and hope i will get more Infos here. Thanks to all poertsch from Germany

@zr2dan can you give me more details about your supercharger and maybe some pics that i can see how it looks on you car. This will me interested for me that i have an overview. You can send me a email or you give me yours and i contact you. Thanks

 

i have a build in this forum called "just a little beefie" there are pics of my blazer there and my supercharger the supercharger is made by wynjammer.com

 

What do you mean when you say builds? Is that gonna cost a lot?

 

Some time ago, I read a great article in Hot Rod mag or Popular Hot Rodding about a build up of a Chevy 4.3L Vortec V6 engine. They were saying that the 4.3 is just a 5.7L with two cyl. lopped off. So they were going to use the same tricks and speed equipment on the 4.3L. They had some success but it wasn't as dramatic as a Vortec V8 of that era which is in balance. The 4.3 V6 is not inherently in balance. Google the Chevy 4.3L build up and see what you find.

 

Another option to increase HP. When the 2014 Silverado's come out, buy a wrecked one with the new aluminum 4.3L V6 and 285 hp and it has a 6 speed auto. In a 'Rado, it is rated at 18 city/24 Hwy. Be sure to get the PCM with the deal. Here's the info from a car blog:
The 4.3-liter V-6 in both the Silverado and Sierra will be rated at 18 miles per gallon city--the same as the Ram 1500 HFE with an eight-speed automatic--and 24 miles per gallon highway, 1 mpg shy of the Ram's best figures. With four-wheel drive, the ratings slip to 17/22 mpg.
GM's six-cylinder puts out 285 horsepower in both the full-size trucks, and sports a maximum tow rating of 7,200 pounds--700 pounds higher than the best Ram V-6. It's also offered in all body styles, and those mileage ratings apply across all of them.

 

there is a variety of performance parts available for the 4.3 i would do a top end kit heads cam shafts and intake you can make about 290 horsepower that way