Anees

Hi guys,

Trying to decide which supercharger kit to go for and I have narrowed the choice down to these two.

Things to note from my requirements:

- As close to OEM reliability and drivability as possible
- I do not want to lower the 9k red line on my car - its kinda the whole point of the 2.0L S2000!
- I want as much power as is safely possible


Pros and Cons that I can see from my research for each kit are:

Kraftwerks Kit with upgraded Rotrex C38-91


Pros
- Quiet Rotrex charger (more OEM like)
- More efficient then the Paxton supercharger on the SOS kit
- Cheaper then the SOS kit and comes complete with everything needed including fuel/ecu and even a base map.
- Seems to produce good torque lower down the rev range compared to the SOS system.
- Engine bay charger positioning seems to be slightly better then the SOS system but not significantly so.

Cons
- Very worrying quality control isses with missing parts or wrongly supplied parts
- Rotrex superchargers do not like to being overspun at all so more of a reliability risk compared to SOS Stage 2 option.
- Similar to the point above, i think 80mm is the smallest belt that can be fitted where I can keep the 9k rpm redline and this seems to limit boost on around 11.5psi so the charger is pretty much at its maximum if I want to keep the existing redline.
- Apparently going for a better intercooler and larger 3" piping might produce more power but its extra expense and will involve trial and error.


SOS Stage 2 with Novi 1200 upgrade and larger heat exchanger


Pros
- Proven product with lots of happy users
- Loads of upgrade options
- Available with a 3.2" pulley that can produce around 16psi of boost to 9k rpm so much more then the standard Kraftwerks option.
- Novi 1200 supercharger has a good reputation for being reliable and can handle being over spun a little (not that I intend to do this!)


Cons
- Not keen on "coffee grinder" bearing noises from the supercharger
- Produces less low down power and torque then the kraftwerks kit (but does have better top-end it seems)
- More expensive then the Kraftwerks Kit.
- Forum reports suggest sos kit is not as nice to drive as the kraftwerks.

Please feel free to correct and errors I have made.

Now I was wondering what people that have experienced both kits think about how these kits actually drive on the road? Dyno figures are one thing but driveability for me is much more important since this is a big investment so I want to make sure I am totally happy with the driving experience of the upgrade.

Please could discussion be limited only to these kits - I have eliminated others from my buying process for various reasons.

Thanks for your input guys.

braeden

It'll be hard to find people that have experienced both systems, most supercharged guys end up going turbo at some point it seems.

I have the SOS Stage 2 with the 3.4", I love it. The install was pretty damn easy, everything fits nice and snug, almost to the point where every other part you want to add to your engine bay you'll have to measure twice to make sure it'll even fit.

I don't think anyone has really regretted installing either kit though, the Kraftwerks is great from what I've heard.

06S2k07Si

^^^agreed.. Although I did try a SOS turbo kit and didn't like the lag (when compared to an S/C) ...but just my personal preference. I'm a die hard S/C guy!

beechx1

The quality control issues from KW are related to them shipping the wrong parts. They seem to be reasonably responsive in getting the right parts to the customer after the customer identifies the problem. I am almost done putting my KW kit in. The quality of the actual parts in the kit is good.

The boost and power levels you mention for the KW kit are associated with the 38-81 blower, but you are asking about the 38-91 blower. Several on this board are reporting 15-16 PSI and up to 460 whp on 93 octane with the -91 or -92 blower (the -91 and -92 have the same air handling characteristics).

LBPS2K06

If you do have kit problems, the guys at Skunk2 bend over backwards to make it right for you. Other than fighting the crank pulley bolt of the KW kit is a pretty easy install. At least it was on an 2006. If you have not done the clutch yet, I highly recommend doing that before the S/C install as all that stuff you hang on the front of the engine just gets in the way when you have to lower the engine cradle to change out the clutch.

Habitforming

I have the kw kit with the basic c38-81 blower and standard pulleys. I have seen a peak of 17.4 psi in my logs, on a cool day. Fwiw

This is on a 2.2l motor though.

gfresh86

Ive had a vortech kit, and now kw kit. 16psi c3891 blower making 460whp. Ap1 2.0 with stock 100mm pulley on pump gas.

soulicious

I see 21psi on cool nights with a 3.0" pulley for my 1200. I'm not using the SOS pulley as that slipped like a mofo in my setup.

96-EJ6

I've had my SOS tuner kit (1220SL, Hondata, ID725's at 8.5 psi) installed for over 5 years now and have only good things to say about it. I have had ZERO issues with the kit in the 30,000 plus miles it's been installed for. My only regret is the small blower, I really wish I'd anticipated my appetite for power and ordered the kit with the 1200, however that's my own fault and easily fixed.

I'm a tech at a performance shop, I've supercharged everything from Civic's and S2k's to C6 & C7 Corvettes and AMG Mercedes. The SOS kit is hands down the most thought out and least invasive kit I've ever worked with. Everything fits PERFECT, the only "permanent" modifications made to the car are two small holes that need to be drilled in the plastic radiator shroud for the heat exchanger lines to pass through, and trimming/replacing a portion the upper radiator hose to clear the aftercooler; both parts are replaceable so the kit is totally reversible! The kit comes with OEM Honda fasteners which is a super nice touch to make the install look factory, no ugly generic hex bolts and washers! The black powder coated compressor cover and aftercooler add to the OEM look.

Driveability is is OEM...until you smash the throttle! It (my AP1) pulls moderately harder in the mid-range than stock, and from 6,000to 9,400 she's in the meat of the power and gettin' it done. Power delivery is buttery smooth and just builds and builds all the way to redline. If I recall correctly my peak torque was at 8,800 rpm and power was just leveling off at 9,400 rpm (again my car, 349whp, 210ish tq on 8.5 psi). A customer's AP2 with the 1200, upgrade heat exchanger, and 17 psi had quite a bit more mid-range than mine does and felt really nice up top.

Upgrades for the SOS kit:

-Order it with the 1200.

-Have them install a TiAL BOV flange on the aftercooler rather than the 1" hose barb and order a TiAL 50mm BOV with a 3 psi spring.

-Get the upgraded heat exchanger.

-Any "high boost kit" is going to require fueling and engine management upgrades, buy QUALITY parts and have your system tuned by someone who is proficient with it.

My final thoughts...

-If your worried about low end power and torque, you should have bought a Z06. The F20C is designed to make power at high rpm, either one of these kits will compliment the natural strengths of the engine.

-The "coffee grinder" noise at idle and blower whine at low rpm become addictive.

-Driveability with either kit will have more to do with the tune than the hardware, both will be perfect with a good tune.

-I have nothing bad to say about the KW kit as I have no experience with it, I'm sure it works great too! I just thought I'd share my SOS experiences.

johnzal

are you using the 650 injectors that come with the kit or a different size???