Comp Oil-Less Turbos?

[DPancoast]

Video of a shutdown test

I don't know if im late to the party, but I guess this is going to be the new thing now? They are cooled only with coolant.... no oil feed or return and supposedly are making a lot of power thus far.

Haven't really found any articles or anything like that yet... just been seeing it mentioned on the MR2 forums more recently with vendors starting to carry them.

[supraghost]

interesting. this would make installation easier.

[11secdsm]

The oil less part really doesn't do anything for me but the new bearing design that doesn't need lubrication is definitely intriguing....especially if it's more reliable and can take more abuse.

[Foolinaround]

Im in for more info,links to then on mr2oc?

[DPancoast]

MR2oc Link

[Foolinaround]

http://www.compturbo.com/technology.html

"Referring now to the turbocharger bearing system, Comp Turbo turbochargers utilize the latest in high-speed ball bearing technology. The acceleration rate of a turbocharger is a function of the rotor inertia and the friction losses in the bearing system. Conventional commercial turbochargers use floating sleeve bearing systems that are a result of years of experimental development. The floating sleeve bearings have an inner and outer oil film fed by lube oil under pressure from the engine’s lubricating oil system. They must also employ a separate stationary thrust bearing that is fed lube oil under pressure from the engine. The friction loss attributed to a stationary thrust bearing is proportional to the fourth power of the radius and can amount to several horsepower at the high speed at which turbochargers operate.

The oil films in conventional floating sleeve bearings have significant viscosity that produces appreciable friction losses due to oil film shear when the turbocharger rotor is accelerated and running at high speed. The friction losses in the sleeve bearing systems and in the stationary thrust bearings result in mechanical efficiencies in the middle 90% range in conventional turbochargers.

The Comp Turbo turbochargers use a ball bearing system that does not need a separate thrust bearing since the ball bearings carry both the radial load and the axial thrust loads. There is little or no oil film shear in ball bearings that operate with rolling friction only so that Comp Turbo turbochargers accelerate much faster than conventional turbochargers that use sleeve bearing systems. The Comp Turbo bearing system is a proprietary design that is unique in the industry. It utilizes full compliment angular contact ball bearings with ceramic balls. Compared with steel balls, ceramic balls in ball bearing have a number of advantages. According to a prominent ball bearing manufacturer, bearing service life is two to five times longer than steel balls, they run at lower operating temperatures and allow running speeds to be as much as 50% higher. Also, since the surface finish of ceramic balls is almost perfectly smooth, they have lower friction losses and lower vibration levels. And, since there is less heat buildup during high-speed operation, they exhibit reduced ball skidding and have a longer fatigue life. All these characteristics make ceramic ball bearings ideal for use in turbochargers where they must operate at very high speeds and survive in a high temperature environment. The full compliment bearings do not use a cage to position the balls and this additional feature, combined with the ceramic material, provides a combination that has minimal friction losses. The mechanical efficiency of Comp Turbo turbochargers that use ceramic ball bearings can approach the high 90% range and this contributes to rotor acceleration rates that have been shown to be faster than competition."

Lots of good info on there,sounds like a great setup. idk about longevity though

[11secdsm]

Interesting read. It's hard to believe they're completely oil-less...would make more sense if they were sealed units like a lot of centrifugal superchargers. I'd love to see long term test results though.

[supraghost]

what do they cost

[jpalamar]

This would make NA conversions a breeze. I'm in for more ifo. Sounds like less turbo lag as well

[SovXietday]

Interesting. Pretty fascinating that the actual ceramic ball bearing has less friction than that of oil at high speeds?! My turbo's ball bearing catridge is an oiled ceramic type which only needs the oil for cooling, so I understand the heat is much less than that of steel. Pretty neat though, going to have to keep my eye on this one.