VWVortex.com - INA Engineering : Official VWVortex Rotrex Supercharger Thread - KITS , TECH & FAQ

# Thread: INA Engineering : Official VWVortex Rotrex Supercharger Thread - KITS , TECH & FAQ

1. pics?

2. There'll be plenty of pics when the kit shows up in the ATL

3. What kind of boost pressure and heat will we see from these chargers?
if we have a OEM crank pully of 5 3/4" = 146mm
and the smallest Rotrex charger pully is 70mm
then that makes it a 2.0:1 engine rpm to charger rpm ratio
that means on a PG engine i would see 6500rpm = 13000
on a built engine i could see 8000rpm = 16000
that would mean the charger input shaft will be spinning
13000rpm or 16000rpm
at 1:7.5 impeller ratio on your largest charger
that equals 97500rpm or 112000rpm
on the C38-61 the flow chart shows a 3.6 - 4.6 pressure ratio
1 psi = 0.7031 grams/square millimetre
at the maxime Charger RPM at 0.40 kg/S
x 3.6 = 1.44 kg 0r 1.4 bar =20psi
x 4.6 = 1.84 kg or 1.8 bar =26psi
the C38-71 shows at max rpm a 0.45 kg/s
x 4.6 = 2.07kg or 2.0 bar = 29psi
this looks goodBUT the flow chart shows 115000 rpm
were the ad says 90,000 rpm Maximum Impeller Speed
NOTE 90,000 RPM limit
so in relality 0.40 kg/s
x 2.8 = 1.12 kg or 1.0 bar = 15.9 psi
This is the largest Rotrex charger on the charts provided
after doing the math on all that data provided i still don't know what
the thermal dynamics are? how hot is the charged air?

Modified by REPOMAN at 8:57 PM 2-1-2009

4.  Quote, originally posted by REPOMAN » this looks goodBUT the flow chart shows 115000 rpm were the ad says 90,000 rpm Maximum Impeller Speed NOTE 90,000 RPM limit

Assuming the use of a 70mm unit.Most Rotrex chargers leave Rotrex with either a 90mm or 100mm pulley

5.  Quote, originally posted by Wizard-of-OD » Assuming the use of a 70mm unit.Most Rotrex chargers leave Rotrex with either a 90mm or 100mm pulley

ok so a stock PG 144mm crank pully at 6500 rpm
90mm = 1.6:1 ratio = 10400 x 7.5 = 78000 charger impeller RPM
100mm= 1.4:1 ratio = 9100 x 7.5 = 68250 charger impeller RPM
on the 3.0l-6.0l charger flow chart
90mm 78000 = 2.4 at 0.30 = .72kg/s = 10 psi
100mm 68250 =2.0 at 0.25= 5.0kg/s = 7psi

Modified by REPOMAN at 8:50 PM 2-1-2009

6. the boost is going to depend on how much air the engine can suck down ass well as the rpm the blower is going to be turning.
The rotrex maps should read just like a turbo compressor map, but you have to have an idea of how much power you are going to make. In the case of a pg, we'll assume 200 crank hp. Convert estimated HP to airflow and it'll give you a better idea of the pressure ratio and rpm that the unit will have to run.

Modified by jwatts at 9:04 AM 2-2-2009

7.  Quote, originally posted by REPOMAN » What kind of boost pressure and heat will we see from these chargers? if we have a OEM crank pully of 5 3/4" = 146mm and the smallest Rotrex charger pully is 70mm then that makes it a 2.0:1 engine rpm to charger rpm ratio that means on a PG engine i would see 6500rpm = 13000 on a built engine i could see 8000rpm = 16000 that would mean the charger input shaft will be spinning 13000rpm or 16000rpm at 1:7.5 impeller ratio on your largest charger that equals 97500rpm or 112000rpm on the C38-61 the flow chart shows a 3.6 - 4.6 pressure ratio 1 psi = 0.7031 grams/square millimetre at the maxime Charger RPM at 0.40 kg/S x 3.6 = 1.44 kg 0r 1.4 bar =20psi x 4.6 = 1.84 kg or 1.8 bar =26psi the C38-71 shows at max rpm a 0.45 kg/s x 4.6 = 2.07kg or 2.0 bar = 29psi this looks goodBUT the flow chart shows 115000 rpm were the ad says 90,000 rpm Maximum Impeller Speed NOTE 90,000 RPM limit so in relality 0.40 kg/s x 2.8 = 1.12 kg or 1.0 bar = 15.9 psi This is the largest Rotrex charger on the charts provided after doing the math on all that data provided i still don't know what the thermal dynamics are? how hot is the charged air? ok so a stock PG 144mm crank pully at 6500 rpm 90mm = 1.6:1 ratio = 10400 x 7.5 = 78000 charger impeller RPM 100mm= 1.4:1 ratio = 9100 x 7.5 = 68250 charger impeller RPM on the 3.0l-6.0l charger flow chart 90mm 78000 = 2.4 at 0.30 = .72kg/s = 10 psi 100mm 68250 =2.0 at 0.25= 5.0kg/s = 7psi

Repoman I respect and trust your word because of the great things you have done.
I have been trying to figure out how much boost the Rotrex put out and was confused by your very valid sounding math, when I came across a mistake you made in the conversion of Kg/s (kilograms per second) and confusing it with “1 psi = 0.7031 grams/square millimeter”
Here in the spec sheet is the conversion, 1 Kg/s x 1731.8 = CFM link
.40kg/s = 691 cfm! And .72kg/s = 1247 CFM!!
Looking at the middle housing with the biggest compressor, C30-94 with a max impeller rpm of 10k and drive ratio of 1:9.49 Using a 100mm pulley 7000 rpm gets an impeller speed of 95659 (100K)
75% line crosses 100k rpm @ .28kg/s and 2.7 pressure ratio

Using this data and this Calculator I get this.

I might have made a wrong assumption somewhere, so please correct me.
If I did the math correct 25 psi and 330 hp! [IMG]http://*****************.com/smile/emthup.gif[/IMG]

edit: oops i used a 2 liter

Modified by Flying Squirrell at 5:01 PM 10-25-2009

8. Keeping an eye on this... [IMG]http://*****************.com/smile/emthup.gif[/IMG]

9. I emailed you guys about your setup (1.9l corrado), I was wondering where are you guys located at?

10. Wow it has been awhile since i wrapped my mind around this. I am sure i was as
thorough with my numbers as i could be.
I believe i got the Conversion table from a Collage website.
if these will produce 25psi thats great. i can't wait to see some Dyno # on a
1.8 8v or a 2.0l 8v or a 1.8 16v 2.0l 16v 1.8 20v. anything in the VW stable
[IMG]http://*****************.com/smile/emthup.gif[/IMG] [IMG]http://*****************.com/smile/emthup.gif[/IMG]
1 kilogram/square millimetre = 1422.32 psi : 1 psi = 0.7031 grams/square millimetre

Modified by REPOMAN at 7:29 PM 10-28-2009

11.  Quote, originally posted by REPOMAN » i can't wait to see some Dyno # on a 1.8 8v or a 2.0l 8v or a 1.8 16v 2.0l 16v 1.8 20v. anything in the VW stable [IMG]http://*****************.com/smile/emthup.gif[/IMG] [IMG]http://*****************.com/smile/emthup.gif[/IMG]

ME TOO! [IMG]http://*****************.com/smile/emthup.gif[/IMG]
 Quote, originally posted by REPOMAN » 1 kilogram/square millimetre = 1422.32 psi : 1 psi = 0.7031 grams/square millimetre

Yes but rotrex specifications dont use kilograms/square mm (measure of pressure)
they use Kg/s = kilograms per second (measure of mass flow rate)

12. Subscribed... and waiting for results

13. Holy crap that's expensive. I wish companies would realize it's less attractive now that the cost of such an upgrade costs 3x what I paid for my G60 to begin with.
Cool deal I guess, I just wish it was 10 years earlier. I'd seen a few other Rotrex G60's over the years. They were about the same power wise as any of the other retrofit kits out there. In the end, no matter what form of boost, you're still stuck with the same CFM potential as any SOHC 8V. [IMG]http://*****************.com/smile/emthup.gif[/IMG]
I still think if someone posted up the specs for brackets to mount the M90, that's the best value out there. The blower alone is \$250 all day long, and it would cost well under \$1000 to get everything dialed in. Trouble is, anytime someone makes brackets, they either horde all the info and keep it secret, or they try to get rich off of it and sell 2 little chunks of aluminum for \$900. [IMG]http://*****************.com/smile/emthdown.gif[/IMG]

14. Well I kind of agree with ya L8, I paid 2k for my rado an this charger setup is going to cost me more than my car . But given this thing replaces a bracket and is included in the kit, the s/c, and everything else for the swap and is "only" 2600, that doesn't seem to bad given other charger setups *cough*lysholm*cough* cost ~400 more and net the same power as this kit SHOULD but only include a charger, pulley and a belt. Plus the rotrex charger is quite which is great IMHO cause it makes able to net the power we want but be quite for a daily drive.
Price is kind of for the car it goes on (cause the cars are obviously getting older and getting cheaper to boot), but compared to any other setup (minus the turbo application, and who honestly wants to replace the s/c for a turbo anyways ) this is prolly the best solution for price to replace the G60 which will eventually catch up in price of this kit.
I honestly can't wait to see the numbers and would love to test one on my car *hint hint* cause I hate replacing a charger ever 10-20k miles cause it gets exspensive QUICK. But that's my

15. To bad the USA is a very long swim otherwise my engine would they ultimate 8V 1825cc testcase.

16.  Quote, originally posted by drkreign » other charger setups *cough*lysholm*cough* cost ~400 more

Yeah, I'm not sure why BBM raised their prices. It used to cost 2600 for the kit. Though, used Lysholm kits usually go for 1500 or so, which is nearly \$1000 less than the Rotrex setup, and more efficient (albeit louder).
Do a search for dynos, there's been Rotrex Corrados that have dyno'd before. They've been around longer than the lysholms have. Numbers are about the same as everything else from what I remember.

17.  Quote, originally posted by L8 APEKS » I still think if someone posted up the specs for brackets to mount the M90, that's the best value out there. The blower alone is \$250 all day long, and it would cost well under \$1000 to get everything dialed in. Trouble is, anytime someone makes brackets, they either horde all the info and keep it secret, or they try to get rich off of it and sell 2 little chunks of aluminum for \$900. [IMG]http://*****************.com/smile/emthdown.gif[/IMG]

Sorry but your logic is flawed a little bit...especially with respect to Rotrex knowledge of the past and current.
You really think an Eaton (Heaton as it is more commonly known in the supercharger world) is the best value out there? I disagree nicely....unless you sit down infront of ebay for an entire year and pick up everyone single M90 unit (or similar) then you WILL be forking over \$2000+ for a new OEM unit.
If you want to be an enthusiast and share information then by all means go right ahead as I am sure many people would LOVE to have that information from you.You let me know what your time is worth....
I have posted this before and I will post this again,for many advertisers on here this IS our bread and butter so we have to look @ every hour that goes by in the day as a means of collecting \$X/hour.
Lets say I would like to be paid \$20 USD/hour to develop a supercharger kit and it takes me lets say 60 hours to develop it.That is 1200 USD of development costs that have to be incorporated into the sale of the kits.Lets say I develop 10 kits,that means each person will pay the following:
* Cost of supercharger
* Cost of materials needed to mount it
* \$120 development cost
* Mark up to cover overheads.
Very few people actually understand the aftermarket performance business model.
There are many people out there that will pay for quality and infact I have been doing my best to grow the rotrex application library.So far we have:
* ABA 16V
* 9A 16V
* ABA 8V
* AEB 20V
* 06A 20V
Now if you are wondering why the PG G60 kit is not done is due to the simple reason that I UNDERSTAND that most G60 owners do not want to spend \$3000+ on a charger kit so I have been revising the kit as many times as possible to get the cheapest configuration done IF we did move to production.That has been one of the major hold ups...
If you want me to spend \$250USD of your money, send me the charger you would like and I will develop a kit for you. You will own all the drawings and development material.Lets see if you want to make it happen.

18. I have searched and haven't found any real data on the WHP numbers on a Rotrex setup for any VW4cyl.
after searching the web the only thing i found was on the
ORZ website stating 195WHP @ 16psi. I believe this is highly suspect
due to the other inflated numbers they show on the web site on other
known setups.
Seems like alot of effort for a Obsolete engine plateform.
in the day of VVTI, MIVEC, and other modern engine technoligy where
little bolt on mods are producing 350+whp it seems an excersize in
engineering over common sence.
A modern engine swap seems the most cost effective way to get
the most performance.

Modified by REPOMAN at 4:34 PM 11-1-2009

19.  Quote, originally posted by REPOMAN » Seems like alot of effort for a Obsolete engine plateform.

As much as I agree with you, you have to remember we represent a very small % of VAG owners across the globe.
The G60 engine ie STILL very much alive in Europe with parts being developed everyday.Unfortuantely I have come to realise that developing parts to sell 2-5 at a time is no way to grow a company.

20. Plus doing a complete motor swap (unless you hold all the parts you've gathered for years) costs the same or more depending on how much you do. This kit shouldn't take very long to install and for the most part just about anyone can install it (with a lil know how of course).
@ 16 PSI IF it's creating ~195 Whp that isn't to bad for this motor. Figure it this way, the lysholm full stage 4 creates ~225 whp according to their site. But most people have placed much lower on that setup, most I have read they end up creating ~195-200 hp. So for this kit you get just as much HP as the lysholm or a VR6 (stock) but don't have the whine of the lysholm OR the price/headache of doing a complete motor swap. To me, that seems like a good combination.
Sam, you NEED to bring this kit out, there are alot of people that want this

21. Doing 256whp with the old Gchager, I hope a Rotrex can beat this number?

22. Not likly to beat 256whp. i only made 236whp on the 8v w/ digi and
i don't think it is going to beat that either.
that being said it is still another option then not having one.
the Gladders are fewer and fewer and the Lysholm 2087 is no longer.
I believe there is going to be a new option for bolt on replacement for
the G60 in the near future from an old trusted tuner.

23.  Quote, originally posted by drkreign » @ 16 PSI IF it's creating ~195 Whp that isn't to bad for this motor. Figure it this way, the lysholm full stage 4 creates ~225 whp according to their site. But most people have placed much lower on that setup, most I have read they end up creating ~195-200 hp.

Stage 4 Lysholm doesn't make anywhere NEAR 225whp. 225 CRANK HP is more like it. I drove mine in that state for years and dyno'd more than once...at sea level, in cool weather.
If the same margin of error can be expected between advertised and actual power on the rotrex, then...I'm keeping my G-Lader, thanks.
The only similar comparison I can find displacement-wise is the Lotus Exige S...it's a 1.8L with a rotrex supercharger @ 7.25psi. However, it also has variable valve timing and lift (Toyota 2ZZ engine). It makes 218 crank HP on that far more advanced 1.8L @ 7.25psi. On our dinosaurs, I would expect significantly less gain...the 2ZZ engine has a compression ratio of 11.5 to 1, compared to the G60's 8 to 1.
As for the Eaton...it's value is contingent on the owner's goals. If you're looking for a more reliable replacement than the G-Lader, then yes - it's the best value, period.
If you're looking to shatter WHP records, then obviously no, it isn't.
REPOMAN said it best I think. A lot of effort, in a very poor economy, to a group known for being cheap to begin with, on an antiquated powerplant! I applaud your effort and your enthusiasm, but you gotta put it in reach of the common G60 owner, most of which are no older than 24 years old!
(I'm older, but no more better off financially than most teenagers unfortunately.)
Make the M90 kit, and price it under \$1200 for everything EXCEPT the charger itself. I would bet you even money that you'll sell FAR MORE of those kits than you will the rotrex.
As a matter of fact, price it under \$1000 and I would personally buy one. [IMG]http://*****************.com/smile/emthup.gif[/IMG]

Modified by L8 APEKS at 9:19 AM 11-2-2009

24. Just checked BBM and they say 225+ hp on a stage 4 lysholm (doesn't say wheel or crank) I just assumed whp, but if the dyno's you were on show far below this then that is crank hp that BBM has posted and at 225 (calculating a 15% drop in power for crank to the wheels) means the lysholm makes ~192whp. Which if that is the case and these kits will produce the same numbers as the lysholm it seems like a no brainer to me (personally).
Rotrex:
No loud noises
makes same power as lysholm
doesn't need rebuilt like gladder does (least not as frequent)
just as efficient as a gladder
What more could you ask for? I mean the price is still high on the kit listed for most of the people on this forum, but, as Sam mentioned the cost to design the setup, plus everything he's selling you, it really seems like the price is very competitive.

25.  Quote, originally posted by drkreign » Rotrex: No loud noises makes same power as lysholm doesn't need rebuilt like gladder does (least not as frequent) just as efficient as a gladder

The lysholm twin screw is the most efficient supercharger on the market - over 80% volumetric and adiabatic efficiency. The G60 doesn't come close to that (60% range IIRC?). So there's a big gap in the middle!
Although the Rotrex is just as efficient as the Lysholm (both blow the G60 out of the water), I'm not sure how to compare them, because the Rotrex essentially a belt-driven turbocharger, with impeller speeds of over 200,000 RPM. It's centrifugal, which means it will not provide the low-RPM boost of the (positive displacement) Lysholm. It should build boost more akin to a turbocharger (more dependent on RPM's).

The Rotrex seems like a very cool unit...but it's just so far out of range for 99% of the G60 enthusiasts here. If someone has the means, pick one up...I have a feeling it will work very well if you've got deep enough pockets!
According to the compressor maps on the Rotrex, it should support enough flow to make over 200whp, depending on which family of charger you're using (C15 is the smallest I think...and up from there). The limiting factor usually isn't the form of forced induction though...I think people fail to break the 200whp mark because of lack of overall airflow (need headwork with the G60 setups because it's not as efficient).
OP...I hope you get some video of a G60 on the dyno with this thing! Please be honest and up front with the modifications on the test car so we have an idea of real world numbers! Let's see some video!
PS...the old Rotrex videos that I used to be able to find maybe 8 years ago are no more...but IIRC, they were using the C15 unit, NOT the C30 unit. If that's the case, this kit (using the C30) should surpass 200whp without a problem.

Modified by L8 APEKS at 11:12 AM 11-2-2009