Up for sale is my "Gen1" Kraftwerks Rotrex kit for a 99/00 Miata.
The kit was purchased in April of 2011, removed from the car in August of 2012 due to CA Smog requirements. It's been sitting in a bin in my garage ever since. The whole kit has 4,000 maybe 5,000 miles on it in total.
This is a RESTRICTED KIT
with NO INTERCOOLER
. It includes a DFC piggyback fuel controller that is set up for a stock 99/00 BP4W Miata and will work with NOTHING ELSE. The kit was ordered for a car WITH AC & PS
and that's what the belts are sized for. If you run this on something without one of those options, you may need to do some legwork to figure out appropriate belt length. The kit as delivered makes about 7~8psi depending on weather and I believe it was originally rated for 180 or so hp in this as delivered "bolt-on-and-go" restricted configuration. There is definitely room to grow but I'll get into that later.
The gen1 kits had some teething problems due to belt alignment because of poor idler design, but I've corrected those issues with my kit and replaced or upgraded appropriate parts to solve the problem.
Once the belt issues were dealt with, I did:
- 4 autocross events
- Sat/Sun back-to-back track weekend at MRLS in the rain (wet belts anyone?)
- Full trackday at Thunderhill including 500mi round trip w/trailer
- Several thousand miles of DD and aggressive backroad hoonage.
...all on the same belt. I consider the belt issue I experienced to be resolved.
This kit is as complete as I can make it, but see the list after the pics for stuff you will need to source on your own. I even have the stickers, licence plate frame and printed instructions that were originally included. I made several improvements to things such as the "fixed idler" guide and replaced all the worm gear clamps on the positive pressure side with stainless T-Bolt band clamps. Info regarding these modifications (and a shitload of other Rotrex tech) can be found in my "build thread" in the Supercharger Section. In fact, I strongly recommend you read that thread so you understand what its taken to get to this point.
I was told by the folks at Kraftwerks that this hardware "should" fit any Miata 94-05 as long as it has a 1.8 engine in it, but the DFC piggyback fuel controller is ONLY good for the NB1 aka 99/00 Miata. You get the DFC with the kit whether you want it or not. (You should get a Megasquirt anyway)
Time for pictures!
Pile o' parts
Idler, tensioner, blower pulley detail.
K&N Filter comes with free dirt!
Oil system and mounts, plus another angle
Rotrex Oil Cooler, I used simple "through the core" transmission cooler mounts rather than the overly complicated ones provided by Kraftwerks.
DFC Piggyback Fuel Controller and Mount on the left
Compressor wheel in all its glory (grey goop on inlet is glue from the restrictor)
Restricted for your pleasure
Original box no less!
This end down you fool!
Bosch re-circulation valve
Fits conveniently in a bin for storage.
Ok, What else will I need to buy to complete this kit?
- Rotrex Specific SX150 Traction Oil.
This is not "optional" or "recommended" oil, this is REQUIRED. Buy it here: https://jacksonracing.com/shop/rotre...raction-fluid/
You could probably reuse the one I've included with the kit, but why be a cheapskate? Buy it here: https://jacksonracing.com/shop/rotre...ex-oil-filter/
The old ones had to be sacrificed but these shouldn't be difficult to find as they are standard R6 Hydraulic Hose. Get fresh hose from Jackson Racing or your local hydraulic parts shop.
- New Sparkplugs with a higher heat range
The NGK BKR7E is what I ran most of the time and it worked great
So what is all this going to cost me?
Asking price is $2,500
Tuxedo kitty can't believe this deal either!
Note: Before you go lowballing me, remember this thing has less than 5,000 miles on it and a C30-74 head unit sells for $2,200 brand new. I've been sitting on this thing for nearly 2 years and its not like its going to go bad sitting in my garage.
I'm in California near the Bay Area and near San Jose. Local sale is preferred and cash is king. I'll be posting this up on NorCalRoadsters sometime later this week as well. I'm willing to drive a couple hundred miles to meet up if you are halfway local. Shipping costs would be covered by the buyer and I warn you, this is not exactly light or compact. I would not be comfortable putting it all in one box. Please don't as me for a damn shipping quote because its not packed and I can't get one yet. Paypal is accepted but buyer would be responsible for fees. Kit is being sold AS IS so don't come after me if you can't figure something out or you blow up your shiza.
As you can see I'm not some 12 post n00b selling random parts with potato pics and no description. I'd consider myself a known quantity and I'm here for the long haul. I'm not here to rip anyone off or make enemies so I've tried to represent everything as accurately as possible.
If you have any questions or would like more info/pics, post up and ask away and I'll try to get back to you ASAP. I encourage you to ask questions here in the thread so I don't get spammed with PMs and don't have to bump things on my own
I know the forum likes to **** up posts with multiple pics, so here is the link to the lot of them on imgur: imgur: the simple image sharer
Beyond the basics:
As with any production supercharger kit, solid gains can be had with the addition of:
- properly sized intercooler
- larger fuel injectors
- programable ECU
- smaller blower pulley
- a solid tune
The redline on the C30-74 head unit is 120,000 rpm. The 88mm pulley that is included with the kit spins things up to around 104,366 rpm if you have a 7,200 rpm engine redline. That is only 86.97% of the C30-74s rated speed. With the restrictor removed, the 88mm pulley is capable of making somewhere in the neighborhood of 225hp with appropriate tune and supporting modifications.
Here on MiataTurbo user Mobius wrote up a great DIY parts list for adding an intercooler to a rotrex kit. It so easy even a caveman like me can do it!
A smaller 80mm or even 75mm 8 rib pulley is available from URD Motorsports: Underdog Racing Development
. Even though the Kraftwerks kit is 4 rib, there are plenty of reports that they work just fine with the revised idler and tensioner setup, provided you use the correct ribs. Going SMALLER than 75mm is NOT recommended as this will overspeed the blower.
The C30-74 blower is actually rated at something like 300hp from the manufacturer so its definitely got some headroom. Unlike a roots or a positive displacement blower, this thing wants to spin, and it wants to spin MOAR. Also unlike a roots or PD blower, its not much for low end torque. The Rotrex does its best work on a roadcourse from 4-5000rpm and up. Unless you really like to wind it out on the street, you may find the performance uninspiring for day to day stuff. I thought it was a hoot but that might just be me.
If this is so awesome, why are you selling it?
I need money for the last of my turbo goodies, plus my car really REALLY needs some paint
If your car looked like this, you would sell your unused supercharger too.