In for 94-97 no P/S and no A/C kit.

Sonofabitch. You ETenn SSM guys are going to kick ass this coming year! Any plans for you to come up to the Finger Lakes Tour? What about Nationals?

This rotrex is going to hit like a SBC!

Man I wish I had the budget for the Rotrex this season. I'll be running in CSP with my ITB setup for 2010. Hopefully learn how to drive my car hard on r-comps and then add more power to it, heh.

Most of the SSM guys are from Mid-Tenn, and yes you better watch out for them all lol. Previous national trophy winners in highly prepped rx-7s and turbo miatas.

A local guy here is running his lotus elise with a BWR s/c kit in SSM. He had been running STM locally N/A and was always close to FTD. I can't wait to see what he'll do with 80 more hp and sticky tires.

I'm going to try to make a few national tours myself, hopefully dixie, finger lakes, and nats. Just got to get my car prepped and prepare myself for an ass beating! This will be just my third year autox'ing, been driving un-prepped STS miatas so CSP will be a fun change.

Rotrex maintenance/reliability?
 

I've been hunting for info on the Rotrex, and waiting for an intercooled '94-97 kit. But I've got a couple of questions...

I haven't seen anything specific about long-term durability, other than simple "they're dead-nuts reliable" statements. What, if anything, typically fails on these things? Does the traction fluid break down or wear out? Does it need to be changed at some point? Does the roller drive wear out?

I suck if these are noob questions that have already been addressed.

We haven't broken any of the small Rotrex units, the C15 in the 94-97 kits or the larger C30 in the 99-05 kits. The only thing that will hurt them are the same things that hurt a turbo: No lubrication, over speeding, surge. The smaller units used in the Miata applications are very tolerant to surge and overspeeding. Unfortunately, we have run William's C30 almost entirely without lube for half a day at an autocross but the unit was none the worse for the wear. Don't do that! Try that with a sleeve or ball bearing turbo and you have stuff going bang.

That's about it. The smaller units used in the Miata applications are pretty much indestructible Every Kraftwerks complete, DIY or Race kit comes with an oil cooler for the Rotrex traction fluid hoses, reservoir, filter and everything needed to keep the Rotrex happy. Recommended traction fluid change intervals are 50k. Run any Rotrex within or at least close to it's redline, keep the Rotrex fluid cooled and it'll run forever.

The Rotrex is mechanically quite a bit more efficient than a Roots type blower so drag on the serpentine belt is lower. The bracket, pulley and tensioner assembly is race proven combination. No belt dusting or other issues. Just as reliable and maintenance free as the belt drive on your A/C or P/S.

Thanks for the quick info! Couple more question... What is the power ceiling of the C15 vs the C30? Could a C30 be fitted to an NA?

Rotrex A/S
Yes.

Do you have a specific power goal in mind?

I'd like to see 200 minimum at the wheels, and maybe as much as 220-230. It's a DD that sees a few track days a year, so I don't want a hand grenade under the hood - and I'd like to keep the bottom end stock if I can. Up top, I've got a stock '99 head ready to go, although I may still do the ex-intake cam swap on it. So with that in mind, am I too far off base?

Also, if I'm looking at the data sheet right, it appears that the C15 maxes out around 200 hp. With that in mind, would I want/need to upgrade to a C30, or would that be overkill?

You will want the C30. You can order a DIY kit right now, figure out your own fueling and piping, or wait for the Kraftwerks production FMIC in a month or two. The production kits for 94-97 making over 200whp are not top priority so I wouldn't expect them until later this year. Until then, you have to start with a either a KW1 base kit or DIY. Kraftwerks has not finalized their engine management solution for the big injectors needed for those power levels.

Just to see what it would do, Oscar has run a C15-60 very close to it's max rpm unrestricted on a stone stock (stock manifold & exhaust) 97 and it made just a tad under 200whp on their conservative dyno on CA91 gas. So figure a breathed on 99 head with a tad more base compression, race gas, blower at max rpm and standalone will likely make 230whp.

The difference between the C15 and C30 in that low 200whp range is that the C15 will be unrestricted so it will be a tad more efficient and have a more linear power band, making peak hp closer to max engine rpm. The C30-74 would develop a tad more torque in the midrange and make peak power at a lower RPM due the the restrictor limiting peak boost up top.

If you are thinking about 230whp on pump gas, you are going to want to build a forged bottom end. For short bursts of street use, stock block is OK. For anything sustained, the stock bottom end on pump gas goes from being a 2000hr motor to a 20hr motor quickly in the 220whp+ range.

Thanks for all the info, Emilio. I hate to keep whipping your ass with questions, but if I think of anything else, I'll let you know. I'll go digest what I've got now...

You'll be surprised to find that I came up with a few more questions...

What do my header choices look like with a Rotrex? Seems to me that its compact size would open things up quite a bit over an MP62 - as far as I know, the Jackson Racing header is about the only mass-market unit that works with that blower.

Will an NB head swap create any screwy fitment issues for an NA kit?

Will the higher-power NA kit use the C30, and will that be compatible with A/C and PS? I only ask because the DIY kit seems to rule out A/C and PS.

Why is the sky blue? (That one's mostly rhetorical...)

1. Any
2. No
3. We don't have a part number for an NA8 4 rib C30 kit for A/C but we could do it easily. Email or call me directly.

Do you need a full PnP kit or do you plan on DIY'inga lot of your build?

4. Refraction

1. Awesome.
2. Awesome.
3. Will do.
3a. Would prefer full PnP if it's in the pipeline, but I'm willing to monkey with it if it's a matter of connecting the dots.
4. You mean it's not because Jeebus is smiling? I may have to begin my downward spiral into hookers and meth now. Dammit.

Emilio-- any news on CARB approval date?

Thanks!

We won't keep it a secret :)

I apologize-- I should have been more specific in my question. When do you expect CARB approval? Are we talking weeks, months, or longer?

Thanks again.

I don't have an ETA.

Emilio--thanks. I will just keep monitoring the forums then. This looks like a great system for me (2002 SE), with the base 160HP unit.

I'm hoping to install something around late summer, so hopefully the calif bureaucrats will get this done!

I expect no CARB rating will be pursued for the I/C upgrade. (Hmmmm, I'm already starting to think of a biannual I/C swap!!)

R/R sounds so easy I wouldn't even consider it a detriment. Just get the damn thing, install it yourself so you know how it goes in, and set aside a few hours before the smog test if need be. Heck, they give you something like a two months warning before the test is due.

I/C set up for the NB's will be CARB.