: Eaton blower research



haterinc
08-06-09, 09:14 AM
ran across this, thought some of you might enjoy it.

noted in there is the "up to 18,000 rpm" which might concern me because i've read 20k+ rpms est for upper and lower pulley swaps at higher boost. just do your research boys and if it can handle it, i'm all for it.

Eaton is finishing one of its best years in the supercharger market, driven by TVS launches for the '09 Chevrolet Corvette ZR1 and Cadillac CTS-V, the first North American applications for Eaton's sixth-generation blower. For each vehicle, the unit integrates with an intercooler.

Eaton has produced some 4 million Roots-type superchargers since 1989. Three years later, Eaton began supplying General Motors Corp. with superchargers for the long-standing 3800 V-6. That relationship lasted more than a decade.

Until the ZR1 and CTS-V programs, Eaton's only other supercharged GM engine was the low-volume 4.4L Northstar V-8 for the Cadillac XLR-V and STS-V.

Eaton began producing its fifth-generation supercharger in 2002 (with Mercedes-Benz as the first customer), and that design consisted of two helical-shaped rotors, each with three lobes that twist against each other to force a large volume of air into the combustion chamber.

Like the fifth-generation unit, the new TVS incorporates two helical-shaped rotors machined from aluminum extrusions. But each TVS rotor has four lobes that mesh together at steeper angles, allowing 160 degrees of twist vs. 60 degrees with the previous unit.

With the fourth lobe and added twist, as well as redesigned air inlet and outlet ports, the new TVS creates a smoother, more efficient flow of air into the engine, says Grant Terry, Eaton's product strategy manager-Supercharger & Cylinder Head Systems Division.

More air into the combustion chamber means more power, which is music to the ears of muscle-car aficionados. The TVS boosts GM's 6.2L V-8 to a trooper-baiting 638 hp in the Corvette ZR1 and 556 hp in the Cadillac CTS-V.

Despite the stampede of horses, the new design makes for a much quieter supercharger, addressing one of the biggest complaints about high-powered blowers. And the new unit isn't any larger than the old one, which will reduce packaging concerns underhood.

The new supercharger operates at a lower air pressure and can spin at speeds up to 18,000 rpm, while the fifth-generation unit was limited to 14,000 rpm, Terry says.

TVS represents a natural progression for Eaton's supercharger product range, Terry says. “We went as far as we could with the 3-lobe rotor” in terms of efficiency and functionality.

Terry's key metric for functionality is thermal efficiency, which he says improves from 62% on the fifth-generation unit to 75% on TVS.

“We're now playing where turbochargers play,” in terms of thermal efficiency.

Turbochargers grossly outnumber superchargers in OEM applications, thanks to the popularity of turbodiesels and the proliferation of turbocharged direct-injection gasoline engines.

However, Terry says some of the new TVS contracts managed to displace turbochargers.

While Eaton trumpets the improvements of TVS, turbochargers also are getting better, minimizing in some cases the tendency to “lag” while exhaust gases spool up the turbines to provide additional boost.

Still, Terry stands by the supercharger as the best bet for instant accelerative gratification. While the turbocharger does most of its work at middle and high engine speeds, the supercharger does its heaviest lifting at low rpm, generally at stop lights.

tedcmiller
08-06-09, 02:14 PM
These words basically confirmed what little I knew about blowers and turbochargers and added considerably to my limited knowledge. Thanks for the info.

wh921
08-06-09, 03:30 PM
Good read, thanks for posting.

wfo
08-06-09, 04:28 PM
Yes, most gracious thank you.

kck
08-06-09, 05:02 PM
ran across this, thought some of you might enjoy it.

noted in there is the "up to 18,000 rpm" which might concern me because i've read 20k+ rpms est for upper and lower pulley swaps at higher boost. just do your research boys and if it can handle it, i'm all for it.....


haterinc:

Thanks for the very informative post.

Question: You highlight the 18,000 rpm limit for the latest generation of Eaton blowers. Am I correct to assume that exceeding this upper boundary is where both efficiency (little power increase) and reliability become a concern? Also, when persons do pulley mods, at what point is one exceeding 18,000 rpm on the Vís Eaton r1900 Ė e.g., when doing more than, say, a 9.5 crank pulley mod?

Finally, I want to alert other forum members to a very interesting related thread comparing the Vís r1900 blower versus the ZR1ís r2300 blower at http://www.cadillacforums.com/forums/cadillac-cts-v-series-forum-2009/176053-bad-heatsoak-help-2.html.

Kyle

haterinc
08-06-09, 05:45 PM
I've read some guys going over 20k revs (est of course) with certain boost levels on the 2.55 upper and 8.5 lower (i think... or was it 9?). I can't confirm or deny that as I didn't take the time to calculate it, but I'm just throwing caution in the wind that this article listed 18k as a max. Not sure if that is coming from the guys who know at Eaton or passed along for the article. I contacted Eaton today and am waiting to hear back from one of their techs about the r1900. I'm not sure about the 9.5", but that is what I'm currently after as well.

NormV
08-06-09, 07:55 PM
Figure out the pressure ratio and plot it out compessor map. The map should be found on Eaton's website.

Norm