Alright, Tony help me understand this a little better. I know you're not a supercharger fan, understandable. However, if you HAD to pick one for a set-up, would this be a viable option amongst the current line-up of Vortech and JRSC on a B series? Eaton, to my knowledge doesn't have anything to offer, nor any company producing twin screws for hondas.

****EDIT*****Eaton is roots right? Not twin screw? Am I losing my mind?

The way I think I'm starting to see it is that the Rotrex kit (appropriately sized of course) won't create instant power like a roots, but won't lag like a turbo or the vortech. The roots on the top end dies and the torque curve gradually decreases. I imagine the vortech would do just fine at higher RPM's, and I guess the Rotrex would fare just as well. Turbo's obviously do well at higher RPM's.

The thing I've seen on a few Rotrex graphs is a linear HP and torque curve. There isn't that on/off boost sometimes associated with turbo's. It also, doesn't just drop off like a roots blower.


http://www.spyderchat.com/phpB...art=0

Here's a lengthy build-up of a rotrex kit in a MR Spyder. I don't quite understand compressor maps, so I don't know if what he says is accuate. However, his numbers seem impressive for a fairly stock 2zz (over 300whp) on a C30-94 rotrex blower. They seem to be gaining popularity in the Toyota camp for some reason.


Modified by 88 rex at 11:13 PM 3/13/2007

 

^

Also made 280ish on a 1zz at one point. I know nothing about Toyota motors but I thought they made 140ish stock.

http://www.worldcarfans.com/tu...arger
http://www.w2wpowertrain.com/t....aspx
2 speed supercharger, but EXPENSIVE!!!!

 

Will,
What is the primary function of this build? ie daily driver + road race vs trailer/drag.
Just wondering

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hondaddy.com &raquo;</TD></TR><TR><TD CLASS="quote">Will,
What is the primary function of this build? ie daily driver + road race vs trailer/drag.
Just wondering</TD></TR></TABLE>

IF this is something that would happen (again, big IF) it would be for daily driver/autox. Drag is not the goal, although those numbers are always appreciated as a point of reference.

This is more of a curiosity on my part.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 88 rex &raquo;</TD></TR><TR><TD CLASS="quote">Alright, Tony help me understand this a little better. I know you're not a supercharger fan, understandable. However, if you HAD to pick one for a set-up, would this be a viable option amongst the current line-up of Vortech and JRSC on a B series? </TD></TR></TABLE>

Do I have to choose? I rather go all motor

Here's my breakdown:

For 300+ WHP:
Turbo &gt; Rotrex &gt; Vortech &gt; JRSC

For 200-250 WHP:
Turbo &gt; JRSC&gt; Rotrex &gt; Vortech

For pure circuit racing and under 250 WHP = All motor or LHT-equipped JRSC

I am a supercharger fan too since I have a JRSC on one of my cars... I don't really try to expect a miracle with a supercharger on the car though, but rather expecting to have a nice peppy car to boot around traffic. That was my goal when installing the SC.

 

I'm the owner of the ITR with Rotrex Supercharger with +375 HP. I'm the only one in the world so far, that have fitted a Rotrex Supercharger to a B-series engine.

The big "problem" is that the B-serie turns counter clockwise, so you have use a dobble sided V-belt, to change the direction on the supercharger.

I have build everything from scratch and didn't get much help, because nobody have tried to use a Rotrex unit on a B-serie before.

Setup:
B16C6
CP 9,8:1 pistons
Eagle rods
ARP headstuds
Rotrex C30-94 Supercharger

It's 2 year ago I build the engine and it have done 60.000 km since rebuild, and right now I have opened the engine to inspect main bearing and pistons. The main bearings was a little worn, but nothing serius. New main bearings and pistons rings, and we are ready for some more action.

I just upgraded with Toda Spec B cam shafts and Golden Eagle cam gears and with +9000 rpm I'm hoping for +400 HP. Putting the engine back together this weekend and I hope for new dyno numbers in a couple of weeks.

I have had people from all over the world, asking about my Rotrex project. Even Oscar Jackson from Jackson Racing have contacted me for pictures and info on the setup :-)

For Trackdays this setup is perfect. The throttle response i crazy and there is no lag. When you hit the gas out of turns, it just pulls like mad and have no trouble with wheelspin, because it don't have so much torque. When it hits VTEC and to the limiter it's the best. I have build turbo cars and there are also fun, but nothing can compare to this setup, without any lag and lots of rpm.
It drives like a NA car, just with twice the power and torque :-)

Sorry for my poor English, but I live in Denmark where Rotrex also comes from.




Early test setup, with the new pulleys. Uses a 6 ribbed doubble sided V-belt.


Boost VS RPM on the dyno. As you can see it have to be over 4000 rpm before making seriuos boost pressure.


365 HP @ 1 bar boost, with belt slipping as you can see on the dyno on the last 1000 rpm. Later made 375 HP, but don't have the dyno sheet.


I use the car as a daily driver in the summer and trackdays and Nürburgring Northloop.




Modified by honda_s800 at 11:56 PM 5/3/2007

 

Wow your set up is impressive. I am also in the process of trying to build a 400+hp rotrex s/c car. I myself seem was pretty skeptic at first untill i purchased the kit from a uk dealer. After installation and some tuning i turn my 2002 honda civic si from a 140whp joke to a 270whp 200trq monster. The best thing about it was that i didnt even get the chance to use the full potential of the kit. It was specifically design for the k20a2 motor found in the ctr. And you are right about your perception of the power, it is basically driving a car with a bigger power. almost like a larger n/a motor. The power band is linear, which is great only problems i found so far is that with the k-series there is so much more trq to worry about compare to the b-series. When ever Oscar at jackson racing decides to release the kit.. everyone will see the power it can really produce.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 88 rex &raquo;</TD></TR><TR><TD CLASS="quote">The thing I've seen on a few Rotrex graphs is a linear HP and torque curve. There isn't that on/off boost sometimes associated with turbo's. It also, doesn't just drop off like a roots blower.</TD></TR></TABLE>

Feed a motor linear increase in boost pressure - for which V.E. drops naturally - and you'll find a fairly flat torque curve. Although boost isn't increased linearly (in that ITR graph), there's always the efficiency to look at - its probably a larger comp wheel thats not that great below 5psi (like most any compressor). I would suspect their reading & pictures don't depict a cvt-like gearbox. They just blab on about it being efficient yet being able to 'grab' - they'd outright say if it was an infinately adjustable gearbox.

While you get better response from a C-SC than a turbo, you still need to raise your rpm before you make much power. It wouldn't be that bad if you had a 4.7FD and b16 gearing. I shouldn't say that they suck all around (they don't), just that for a Honda, there's easier & more effective ways. In that ITR's case, I'd have just modified a whipple.

 

Rotrex blowers have a fixed drive ratio. It says it in the Rotrex documentation. They are working with a company to make a variable ratio electronically controlled drive system, but it will use a motor to spin the blower at low engine RPM and is still in testing, where it's been for years. If they get it to work, then it might be pretty cool, but it sounds very "electric supercharger" to me.


As far as the information in this thread about Roots blowers, it's all wrong. A supercharger has a compressor map that shows you what it's efficiency is, just like a turbo. If you run it too far outside of its efficiency range, then it will make a lot of heat and power will drop off, just like a turbo. The problems that are seen with Roots blowers are due to the fact that the biggest production model that spins CCW (making it compatible with a B-series) is an Eaton M62, which can't push enough air to keep up with a B-series at any significant pressure ratio. A Roots blower that is properly sized for its application will make power to redline and be 70%-75% efficient, just like a turbo. The math is pretty easy, and manufacturers publish their compressor maps, this isn't rocket science.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Weighing 3.9kg the supercharger drive system is not only lightweight but efficiently designed with a length of 149mm (5.9 inches) and diameter of 170mm (6.7 inches). At engine speeds below 4,200rpm the device provides a gear ratio of 1.36-to-1. Above this speed the drive is direct. The mechanism is entirely self-changing with no electronic<U></U>, hydraulic or pneumatic control systems and the shift point, which can be set to any desired engine speed, is highly consistent. The drive can be retro-fitted to Rotrex C15, C30 and C38 superchargers. </TD></TR></TABLE>

 

to honda_s800, very nice engineering and setup, I have a feeling your worn bearings could be from the solid crank pulley, by turning high rpms with that kind of power, the harmonics eventually have to take a beating on your oil pump and bearings. would be nice if you could engineer a way to attach a pulley to a fluidamper or ATI pulley.

you could pickup that extra 25whp just in getting a very nice header.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">Weighing 3.9kg the supercharger drive system is not only lightweight but efficiently designed with a length of 149mm (5.9 inches) and diameter of 170mm (6.7 inches). At engine speeds below 4,200rpm the device provides a gear ratio of 1.36-to-1. Above this speed the drive is direct. The mechanism is entirely self-changing with no electronic<U></U>, hydraulic or pneumatic control systems and the shift point, which can be set to any desired engine speed, is highly consistent. The drive can be retro-fitted to Rotrex C15, C30 and C38 superchargers. </TD></TR></TABLE>

It seems the big company here in the states that is designated as a the us dealer is Wheel2wheel. Basically they already have a 2-speed rotrex supercharger on the New mustang and hummer. I have been reading up on this in the last couple of days. Google is a wonderful search tool, basically it is suppose has the capability of better boost level in low rev range and still keeping the high boost in high rev. This is basically what everyone has been asking for. If you can imagine the possibiilty of power from a twinscrew s/c in a centrifugal format then you basically have what wheel2wheel has accomplished. Now shed out some $$$ and put that on a honda.

some pictures of a 2 speed rotrex supercharger!





Image from http://www.gizmag.com


Modified by 209_k20a3 at 3:05 PM 5/16/2007

 

How do you mount these thing or where on that or the other would you mount a bracket

 

i am building a b20 rotrex DA9

 

THIS THREAD IS FROM 2007

 

That **** needs a bump!

 

 

 

Considering the Kraftwerks B-series kit is officially released now, can anyone share their results & experiences with this kit?

 

Dude make a new thread this **** is old and outdated

 

Brang it bakkk!

 

No. DO NOT start a new thread. there's already one here you can inquire from.

https://honda-tech.com/forums/forced-induction-16/kraftwerks-b-series-race-supercharger-kit-unbelievable-gains-3143249/

 

Chillinit make a new thread!!!!!!!! This place is dead no one is going to go in that thread shodan posted

 

yea I mean there's the "official" rotrex/kraftwerks thread (if you can even call it that) but no one has really completed the whole process and those who have aren't making the best power with the unit, certainly nothing like a bunch of major Honda/Acura companies have claimed.


the biggest problem is that it's still a centrifugal supercharger so boost is entirely rpm/pulley dependent and you'll only make peak pressure at the end of the rpm range. so you loose a lot of the down low grunt the roots type chargers have, which dies off at roughly 3k when you compare it to a typical stock motor with a basic turbo kit.

somewhere on here was a comparison thread of a gsr with a drag stage 3 turbo kit and a jrsc kit but I can't seem to locate it and the dyno charts are long gone.... but basically from idle to 3k the jrsc made more power and torque and from 3k on the turbo power curve took off and never looked back.

with a centrifugal sc you basically loose the low end gains and make a "fair" amount of power elsewhere, however, it still wouldn't come close to the midrange and top end power/torque that even the most basic of properly sized and tuned turbo setups produce.

honestly I don't really see the point of a supercharged small displacement motor... superchargers work much better on larger displacement motors (like v8s) that produce lots of torque early in the rpm range and don't rev as high.

roots type chargers make boatloads of low rpm torque on big motors but it's so much torque it can't really be put down effectively without a decent amount of chassis work. this is also the reason why a lot of v8 guys run centrifugal setups...

they already have enough torque down low as is... probably enough where traction is an issue if you get on it hard in lower gears, this is an area where the centrifugal won't really improve upon given it's rpm based boost pressures. so you don't get all of the traction issues of a roots type but you still see a power increase from the midrange to top end, where most large displacement motors start suffering from a serious power drop off and this is another area where a roots charger will have very little, if any, effect on power production in the midrange to top end.

each type of supercharger (roots, screw, vane, centrifugal) has their pros and cons but on such small displacement, high rpm, "peaky" motors there really is no benefit, at least not over a similarly sized turbo kit. especially when you consider the cost of the KraftWerks race kit and the additional fabrication that is required to get it up and running.

don't get me wrong, I like the KW stuff but it's been documented that they work much better on the larger k20/24 motors. The guy who posted here from Denmark is probably the only b series car I know of with a rotrex making that much power...

Skunk2 hyped the KW B race kit pretty hard but their dyno testing and results were anything but impressive and conclusive... if you've seen the "video" then you know exactly what I'm talking about.

But that's just my point of view.