wu`

I've been trying to find more information regarding the Kraftwerks Rotrex Supercharge K Race kit for K series. I've tried messaging Kraftwerks on K20a.org and I haven't gotten any responses yet.

I'm from Australia and one of the few K swapped cars here so it extremely hard to find any information from locals about American parts.

I dont have any power goals but I'm looking for something reliable, street-able and I can actually use the power on the track (i.e. circuit) with no traction issues.

I haven't been able to find any information regarding what size supercharger to use on the K series in terms of my goals with optimum power. I've read people using the C38 series and also the C30 series but I'm not sure what sized drive pulley they're using. The C38 is supposed to be good for 500hp+ and the C30 for something around the 300hp mark.

Does anyone have first hand experience with the Rotrex SC to be able to give me some feedback or ideas on what i can do?

HiProfile

The issue is that the Rotrex is still a centrifugal supercharger. THe gearbox is 'special' & compact, but that's about it. You still get X-amount of boost based on RPM. Centrifugal SC's are uncommon on Hondas because the inherant lack of low-end power, and the rising boost doesn't help that. Big motors work well because many peak halfway to redline but have tons of low-end power, so the rising boost basicly makes up for the poor volumetric efficiency they have up high.

There is a thread on a b-series ATI S/C that is a pretty good example. It doesn't make 300whp (WITH an intercooler), has to spin past 9k to even make what it does, and looks like a NA B16 at all RPM's before 6500. Poor investment IMO. For the same price and some thought put into it (such as header wrap, shroud for slimfan, etc), you can get everything AND more with a turbo.

One thing you might want to look into is an Eaton SC. Roger McDaniels modded one to work on a b16, and it makes a crapload of power at ANY rpm. It also uses an FMIC, and runs nearly ambient IAT's. An M90 or M112 for a K20 would make 300whp on low boost, and the larger would make past 600whp with a good amount of boost.

The only issue I see is you might be looking for a pre-fabbed setup. In that case you're kinda screwed if you want any extra [noticable] low-end power.

wu`

I was planning to do my own piping, fmic, etc. My other option was to run the Full-Race GT2 turbo kit with the GT3037R but I'm not sure if i want to be running that on the track.

I'm after more mid-range to top end power.

My cars currently making about 200whp with i/h/e, cams, rc 650cc injectors, kpro. I also have a cusco 1.5 way clutch type lsd so i dont want to abuse it so much until i upgrade to a quaife.

HiProfile

A GT30 could get your K20 spooled to 10psi by 4k rpm, and make 350-400whp at that low level. A GT28xx with a .82ar housing would make a stellar track wh0re out of the K20, still getting you decent topend (400whp with a 72r and decent boost). It would be considered small for a drag car, since that's almost always the focus on HT.

As I usually do now, I recommend you head over to the evans-tuning dyno library. They have many different setups listed, and many F-R kit combos tuned.

If you are concerned about heat, just make sure you wrap everything at least once, if not twice. You will also have zero issues with coolant once you get something like a SPAL fan on a shrouded radiator. I'm sure you're handy enough to fix the slight deficiencies a turbo setup brings to the table, any OG fabricator who does their own piping can.