Jackson Racing Rotrex Supercharger System Info and Discussion

[Sellout]

Originally Posted by Calum

I wonder if the rotrex drive system is designed to slip some at high rpm.

I understand that the differences in low end torque delivery aren't there, I've seen some dynos to. But I wonder if that was a part of the design, to make it slip some at high rpm so it can be spun faster at low rpm without over spinning it. Kinda reminds me of quick bleed down lifters if that is the case.

If it was, then they failed miserably since the boost curves are identical with other centrifugal boost curves.

Also: Have you ever seen the clutch-packs removed from an automatic transmission after they've been overpowered? Even with plenty of cooling fluid circulating, things are toasted pretty quickly from slipping...

[Calum]

Originally Posted by Sellout

If it was, then they failed miserably since the boost curves are identical with other centrifugal boost curves.

Also: Have you ever seen the clutch-packs removed from an automatic transmission after they've been overpowered? Even with plenty of cooling fluid circulating, things are toasted pretty quickly from slipping...

Maybe. Maybe the higher top speed means the low range would have been much worse otherwise.

[Sellout]

Or it could be that everyone has been sold a bill of goods. Rotrex doesn't say that they develop more midrange. That entire idea came about on an internet forum full of people trying to interpret what the Rotrex wording meant.

Nobody wanted to believe it when the actual dyno sheets showed nothing like what they were expecting, and since nothing ever goes away on the internet, we're all still talking about it years and years after the fact.

This entire issue is exacerbated by the people who make or sell rotrex based kits never bothering to correct anyone on this idea that rotrex kits have mythical boost plots...

BTW - The Rotrex data shows max drive efficiency of 97%. This whole idea that the impeller can spin at a speed that is higher than the drive ratios dictate, should mean more than 100% drive efficiency shouldn't it?

Also - people have seriously been saying this about Rotrex kits for years and years. Shouldn't someone have come up with a video or a dyno plot showing boost spikes or an incredibly flat torque curve by now if there was any truth to this rumor at all?

[OICU812]

@Sellout thanks for sharing your research I learned a shitload. While I wouldn't expect magic from a Rotrex and now understand it much better they do seem reliable? I've been searching S2K forums for users experience with the Rotrex as to me lots of this is new. Consensus seems to be very favourable in regards to reliability and drive ability when tuned well and with caution.

[CSG David]

Originally Posted by vgi

to me primary advantage is 50K vs 7K oil change, easier installation, and no issues or loss of warranty when it's cold out in winter time. also, not sure if these JR and KW kits will have any issues but a fair amount with Vortech seems to be having belt slipping issues.

Keep in mind those numbers are for the standard maintenance schedules. If you intend to track the kits pretty regularly, aka around 12+ times per year, and have a personal record of being at the top pack of the day, then additional preventative maintenance should be considered on all fluids in the vehicle. Heat breaks down everything over time (various schedules) and as a PREVENTATIVE MEASURE, it's always better to change it out a little earlier than later. Preventative maintenance on properly driven cars will keep your car running for a long time with minimal downtime.

As for belt slip, I understand it in my head, but I can't quite put the words to explain the function of belt slip. What I do know is excessive belt slipping or breaking is a function of poor engineering design. As for Vortech's belt slip issue, those inquiries should be sent directly to Vortech. This particular thread isn't to discuss Vortech's issues.

[utekineir]

The vortech oil being cheap and schedule roughly paralleling engine oil changes doesn't sound too bad.


I mean it looks silly easy to drain and refill while waiting on the engine to drain during a normal oil change

[Sellout]

Originally Posted by OICU812

@Sellout thanks for sharing your research I learned a shitload. While I wouldn't expect magic from a Rotrex and now understand it much better they do seem reliable? I've been searching S2K forums for users experience with the Rotrex as to me lots of this is new. Consensus seems to be very favourable in regards to reliability and drive ability when tuned well and with caution.

Glad to help! I honestly just hate seeing this constant stream of misinformation about Rotrex systems. Damn myth just won't go away...

They are as reliable as any other well known supercharger brand, and very efficient. It's a good product.

[tonylop33]

I got to experience the acceleration and instant torque of the Jackson kit at the hands of Oscar Jr. He gave me a ride in his car yesterday. The car pulls and responds as if a totally different engine had been dropped in. This is how the twins should have come from the factory. Thanks for the demo ride Jr.

[sklimo]

Originally Posted by tonylop33

I got to experience the acceleration and instant torque of the Jackson kit at the hands of Oscar Jr. He gave me a ride in his car yesterday. The car pulls and responds as if a totally different engine had been dropped in. This is how the twins should have come from the factory. Thanks for the demo ride Jr.

You are killing me lol. Dying for my kit to come in and get installed

[mad_sb]

Originally Posted by Sellout

If it was, then they failed miserably since the boost curves are identical with other centrifugal boost curves.

Also: Have you ever seen the clutch-packs removed from an automatic transmission after they've been overpowered? Even with plenty of cooling fluid circulating, things are toasted pretty quickly from slipping...

No, that is not how they do it from what I understand. My understanding is you use a small enough pulley to get boost down low then you use an inlet restrictor to limit the boost up top. As discussed:
http://www.spyderchat.com/forums/sho...ion-for-Rotrex

[mad_sb]

Originally Posted by CSG Mike

Yes, you can via restrictor, but it has not been engineered in this application, since it's not necessary, and the Rotrex is already being spun up to about 90% capacity.

I understand your point. However, I would not go so far as to say it's not necessary... Certainly the gains up top are leadingthe SC charts for the rotrex duo, but if you want more bottom end your probably going to need to limit the top end. I just assumed if they had the ability to crush vortech up top and innovate down low they would have designed the kit to do just that with more boost down low and about the same up top.

[Sellout]

Originally Posted by mad_sb

No, that is not how they do it from what I understand.

Thanks for that.

[CSG Mike]

Originally Posted by mad_sb

No, that is not how they do it from what I understand. My understanding is you use a small enough pulley to get boost down low then you use an inlet restrictor to limit the boost up top. As discussed:
http://www.spyderchat.com/forums/sho...ion-for-Rotrex

Originally Posted by mad_sb

I understand your point. However, I would not go so far as to say it's not necessary... Certainly the gains up top are leadingthe SC charts for the rotrex duo, but if you want more bottom end your probably going to need to limit the top end. I just assumed if they had the ability to crush vortech up top and innovate down low they would have designed the kit to do just that with more boost down low and about the same up top.

I understand what you're saying. You want to ramp up the boost faster, and then restrict it, so that peak output isn't dramatically increased. What I'm saying is that there's only about 10% overhead left, so you can ramp up the boost 10% faster and still stay within the Rotrex's manufacturer's specifications.

[TrogDor the Burninator]

I thought I had read on the Kraftwerks thread that with their kit at 7400 RPM the Rotrex was spinning closer to the max rpm suggested by Rotrex than 90% ...

Is it different on the Jackson Racking kit? I understand the belt systems are different, but at 7400 RPMs with the JR pulley in the kit - is it spinning the Rotrex at 90% of suggested maximum RPMs?