There are a lot of questions about STS vs. Radix, Radix vs. ATI, STS vs. Front mount turbo, etc., so this thread is a place to store all that info so we don't have to keep retyping it every time someone considers FI for their truck. I'll start out with my answers to these questions, which reflect my experiences and research (your mileage may vary so speak up), this is a sticky so we all have a common thread to that people can read at their leisure and so we can report new info.

Let me be the first in this thread to say that the best option for you depends on your goals, desires, targets, money, etc. There is no one-size-fits-all FI solution and there never will be because each method brings its own inherent strengths and weaknesses to the table. Almost ANY FI kit offers the potential of going stupid fast.

Here are my pros/cons for each system I thought of (some of this may be out of date, so PM me with details if you see something and I will correct my list):

STS : Squires Turbo Systems : Rear mount turbos
Strengths:
1. power potential -- turbos in general have more potential to make big horsepower, most of the time exceeding the engines capability to make power
2. Well designed kit (and being refined all the time)
3. Kit price is inexpensive, but the kit itself is incomplete if you want to make big power
4. No parasitic drag (although an argument has been made that the increased exhaust pressure effects the engine's efficiency)
5. Variable boost -- at the flip of a switch (with an upgrade to the basic kit), you can have 'everyday' boost and 'race' boost
6. Capability to grow with you as your goals grow
7. Easily modded
8. Doesn't require $1000 in exhaust parts to make max power
9. 1 year warranty
10. STELLAR customer service
11. multiple intercooler options including air to air, meth/alky/water injection

Weaknesses:
1. kit requires welding / minor fabrication
2. kit needs more parts to make big power (see #3 above), but most are available from STS as options (injectors, tune, fuel pump, cooling method)
3. no boost until the turbo spools up (I'm not going to talk about lag here, as lag is generally misunderstood / or assumed to be the same thing as a turbocharged 4 cylinder's lag).


Radix Magnacharger - Roots-hybrid supercharger
Strengths:
1. Instant torque -- any time, all the time
2. Intercooled
3. Very complete kit - intercooler, all necessary parts, pump included on 03 models
4. 'Easy' install -- no welding or fabrication, most people with basic wrenching skills can do this
5. Nice long warranty as long as you use the superchips tune -- 3 Year 36K mile Drivetrain warranty is additional cost ($200) and the install must be done by an ASE certified mechanic
6. Nice community support (Hey Brian!)
7. Someone weigh in here on customer support, but my feeling from talking to others is that it is STELLAR (comments from an owner: customer support is great, calls returned, you get to talk to technical people in the USA)
8. Great track record
9. Really shines at 7psi in terms of abidactic efficiency compared to similar style blowers (i.e. non-cent blowers)

Weaknesses:
1. Expense of the 'basic kit', which is probably the most complete FI
2. Ultimate power potential is limited, but limited to ~500hp which is enough for 95% of the world
3. Changing boost is more difficult than with turbos (pulley change)
4. Belt slippage (although maybe not for 3.1" pulleys) -- Guys with Radix's please let me know if you have slippage issues - if not, let's get this one out of here
5. Needs full exhaust for maximum potential
6. Parasitic loss

Whipple - Twin Screw Supercharger

**note: these are all based on the Lysholm kits and all is subject to change with the new in house compressor**

Strengths:
1. Very high abidactic efficiency -- more than the radix according to the source (WHIPPLE...), but it is not really an apples to apples comparison. A/E is affected by ambient temp, and is pretty tightly coupled to the compressor variables -- so until we see data from a controlled test of similar boost levels in the same ambient conditions)
2. Complete kit
3. Instant torque from 1500 rpm up
4. In the upper rpms, this is probably more efficient than a radix
5. at ~15psi the abidactic efficiency is much better than the radix at the same boost (whereas 7psi vs 7psi the A/E favors the radix)

Weaknesses:
1. No intercooler
2. ECM is a piggy back system
3. Only comes with two add on injectors
4. Customer service leaves a lot on the table
5. No resale value -- Whipple requires s/cs to be evaluated and updated in order to flash the computer... I was told this always leads to at least $1500 in charges by a whipple employee
6. Parasitic loss
7. belt slippage
8. Needs full exhaust for maximum potential
9. pulley change to change boost

ATI - Procharger - Centrifugal Supercharger (most of this is old-- from my 5.0 days)
Strengths:
1. Higher power potential than Radix or Whipple, less than turbo
2. Great track record
3. Almost instant torque
4. Easy install
5. In my 5.0 days, customer service wasn't too hot
6. I've been told the cost of these has come way down to around $4k -- that's a good price

Weaknesses:
1. Kit needs more parts for maximum potential (injectors, intercooler -- although a FMIC is available from ATI as an option)
2. FMIC is not super efficient
3. Belt slippage requires special mounting brackets to turn up the boost
4. pulley change to change boost
5. Install is easy, but very involved.
6. Peak power only at shift point (these require impellor tip speed to make boost)
7. high parasitic loss

Vortech - Centrifugal Supercharger (5.0 days again)
Strengths:
1. Same as ATI
2. Vortech has been around forever... Chances are if there is some problem with a centrifugal s/c, vortech not only has a solution, but invented the problem
3. Available air-to-water intercooler
4. LOTS of available options
5. Complete kit
6. Good support in general, but not much for GM trucks

Weaknesses:
1. Cost of the kit
2. Cost of maintenance
3. Peak power only at shift point (these require impellor tip speed to make boost)
4. high parasitic loss
5. belt slippage issues as boost increases

Detroit speedworks, PTK, CM, LM -- Front mount turbo kits
Strengths:
1. Most power potential of any FI option discussed here
2. The "in thing" in go fast
3. Since I am lumping several kits in here, I can't address the individual things of each kit, but generally speaking, these kits are complete, and ready to go

Weaknesses:
1. Underhood temps skyrocket
2. Need heat reducing steps in addition to FMICs
3. Since I am lumping several kits in here, I can't address the individual things of each kit, but generally speaking, may require extensive fabrication, loss of A/C, etc.
4. Expense of the kit, plus install

I'd love it if you guys with front mount kits would either post up or send me the strengths/weakenesses and I'll edit them in for your particular kit.

I'll let someone else address n2o since I've never used it or researched it.

Other kits coming on the horizon: W2W kit (I think -- Kurt?), and the Rotrex-based s/c also from W2W Maybe we can get Kurt to drop in and give us the scoop on these kits.

Not reviewed: the alternator-drive s/c (wynjammer??) if anyone has some real info, please post up.

Here's a linky to the track times thread for comparison of 1/4 mile times of SSS's with these mods.