How does a BB turbo work?

[rs4rush]

I was talking today about BB turbos with Justin and we both dont know how they work from a standard turbo? So how do they work?

I searched and could not find info...

[MDCmotorsports]

In a standard journal bearing turbo, you have a thrust stack, a thrust bearing, and journal bearings.

The axial thrust is controlled by oil pressure and the thrust stack wrapping around the thrust bearing.

The thrust bearing is kept in place by the front oil seal carrier / backing plate.

The radial thrust is controlled by oil pressure and large journal bearings.

In a ball bearing turbo, both axial play and radial play is controlled by the ball bearings themselves inside the bearing cartridge.

[Frankenstien]

^ Ok, I'd like to know what are the advantages/disadvantages of each? Which is better for a performance car, and which is better for a dd?

[Clip]

bb is the pro way to go, also more expensive. i believe that if you have two turbos of equal size, the bb will spool faster than the thrust bearing.

[Doward]

It spins :)

No, seriously. Ball bearings are simply an evolution from the journal bearings. While the ball bearings are much more susceptible to debris, and much more finicky about oil flow - they are superior in practically every possible way, in terms of friction, ease of spool, etc.

[Clip]

hence the price tag :D

[MDCmotorsports]

Also note that ball bearing turbos have yet to prove them selves in terms of life span VS journal bearing turbos.

The filter technology and oil technology IMO have not caught up yet to the extreme precision and RPMS that a ball bearing turbo sees.

[Frankenstien]

Thanks very much for the info. Is there any way to increase the life of a BB turbo aside from change the oil every 3000km, like upgrade the filter system somehow? I was thinking have two types of oil filter in a row with a relocation/cooling setup :dunno:

[adampecush]

adding a bypass filter along with a conventional filter should help to keep down the size of the particulate matter in the oil.

[sneakypete]

i went with a dual filter relocation and use a wix conventional filter and a trasko filter to keep everything clean. with this system, you dont have to change the oil as often... all you have to do is change the filter material. before i went with this system, i would change my oil every 6000 miles. but now, every 6000 miles i change the wix filter and the trasko filter element. and then change the oil along with the filters at 12000 miles.
also go with a full flow system and upgrade the oil cooler.
-pete

[Frankenstien]

Thanks for the info guys, really appreciate it.

[bmoss85]

i was wondering what is the differences between dbb and tbb, and what if any are the advantages of the tbb over the dbb?

[MDCmotorsports]

i was wondering what is the differences between dbb and tbb, and what if any are the advantages of the tbb over the dbb?


Frankly I feel this is a gimmick. A tripple or even quadruple ball bearing is simply sharing the axial load through a set or two sets of duplex pair bearings.

Instead of one bearing controlling inboard thrust and the other controlling outboard thrust you now have two controlling one way, and one controlling the other or vise versa.

Make sense?

[bmoss85]

thanks i was trying think of how it would work. i wasnt sure if it was really needed, or if there was really any performance gain from it.

[Flateric]

It spins :)

No, seriously. Ball bearings are simply an evolution from the journal bearings. While the ball bearings are much more susceptible to debris, and much more finicky about oil flow - they are superior in practically every possible way, in terms of friction, ease of spool, etc.

I was under the impression the BB turbos are much MORE forgiving about oilflow conditions. Or perhaps I am misunderstanding this links information. Don't get me wrong I am no expert and very likely have only 10% of the technical knowledge of most so I simply am trying to get down to the actual bottom line differences.

http://www.turbobygarrett.com/turbobygarrett/images/Multimedia/Leaflets3_2.jpg

Or as I said I may have misunderstood something more than likely.

[MDCmotorsports]

I was under the impression the BB turbos are much MORE forgiving about oilflow conditions. Or perhaps I am misunderstanding this links information. Don't get me wrong I am no expert and very likely have only 10% of the technical knowledge of most so I simply am trying to get down to the actual bottom line differences.

http://www.turbobygarrett.com/turbobygarrett/images/Multimedia/Leaflets3_2.jpg

Or as I said I may have misunderstood something more than likely.

What paper says and what real world conditions report back are two different things.

[Nick M]

What paper says and what real world conditions report back are two different things.

Ain't that the truth. Beause it doesn't seem like a steel ball has lower friction than oil. But they sure do respond faster.

[Toy-Rific]

I was under the impression the BB turbos are much MORE forgiving about oilflow conditions. Or perhaps I am misunderstanding this links information. Don't get me wrong I am no expert and very likely have only 10% of the technical knowledge of most so I simply am trying to get down to the actual bottom line differences.

http://www.turbobygarrett.com/turbobygarrett/images/Multimedia/Leaflets3_2.jpg

Or as I said I may have misunderstood something more than likely.

I am on the side that a Ceramic Ball Bearing, being dual or triple is the better way to go.
Greg\Lipp

[EVOlutionary]

One thing I've thought about is that on start up and shut down a journal bearing turbo loses all oil pressure and for a moment spins directly on the bushing. A BB turbo, however, still has the shaft supported by the bearings. On my friends DSM with a BB FP 3052, the wheel keeps spinning for about 2 minutes after you shut the car off. This, to me, shows the great decrease in friction you get with a BB setup. . .

No expert here. Just my observations. . .

[Nick M]

Just like the engine crankshaft. Luckily, there is no load.

[Frankenstien]

Frankly I feel this is a gimmick. A tripple or even quadruple ball bearing is simply sharing the axial load through a set or two sets of duplex pair bearings.

Instead of one bearing controlling inboard thrust and the other controlling outboard thrust you now have two controlling one way, and one controlling the other or vise versa.

Make sense?


So wouldn't a QBB be the way to go? 2 bearings for inboard and 2 bearings for outboard? I wouldn't think there'd be much sacrifice in spool time, but there would be an increase in longevity due to the equally divided strain on four bearings rather than two?

I also have another thought on this: Would it not be possible to get more longevity out of a turbo by making one with both journal bearings and ball bearings? Or is that not feasable?

[Frankenstien]

^ Just curious if it's possible. :)

[Doward]

What would the journal do, that the ball bearings were not already doing?

[Frankenstien]

I don't know, maybe having a journal in there would keep the turbo from failing as fast as an ordinary BB turbo? Just an idea I've had floating in my head for a few months.

So having said that, would a BB turbo with 4 bearings rather than 2 (DBB vs QBB) be better longevity wise, comparable to a journal bearing perhaps, or even longer maybe? I think it's a good idea.

[gaboonviper85]

I'm no expert let me just make that clear..

I don't think it matters how many bearings you have....the fact is that ball bearings have moveing parts....yes ball bearings have less resistance but let's say that your turbo is spinning at 100,000 rpm those bearings are produceing massive ammounts of heat and need to be cooled (aka oil flow)... A little hickup in the flow could be enough for the bearings to cook themselves......not only that but you get the slightiest ammount of dirt in the oil and it makes it to the super high precision bearings they are toast...

A standard bearing has no parts...shaft just rides on a pocket of oil...nothing to wear out....nothing to break....nothing to generate heat....although this setup sucks for boosting it's a superior design with our oiling systems....

Now if we could have some auxillery turbo oiling system that had it's own pump and it's own oil then bb turbos are risky.

Again it doesn't matter how many ball bearings you have as they don't see much load anyway...the only load is in the compressor and turbine...

This is my "guess".....I make parts that spin well over 100,000 rpm...spin so fast the bearing races need to be bolted to the parts themselves and the bearings are custom made,,,$6000 a bearing....

[bmoss85]

Now if we could have some auxillery turbo oiling system that had it's own pump and it's own oil then bb turbos are risky.

not a bad idea, probably wouldnt be hard to do. electric pump and an external reservoir. iirc sts turbo kits use an electric pump to get the oil back to car from the turbos. but if that pump were to fail well, it would be time for a new pump and turbo.

[Adjuster]

I thought about hooking up my oil feed line from the bypass filter.. The oil would be as clean as possible, and it would restrict flow somewhat, to keep oil smoke down on the turbo.

In the end, I just used a restrictor oil fitting, and it seems to be working fine.

I'd need some idea of how much oil is being filtered through the bypass filter before I committed a turbo's life to that flow. (Right now, I'm just dumping the bypass filter oil back into the pan, via the stock oil cooler location fitting.)

The rest of the oil goes through a Canton full flow filter that's rated to 8 microns. (The bypass is rated to 1 micron or better.)

Oil Guard, the bypass filter guys, say about every 45 min of use, on most vehicles, the oil is all filtered through the bypass filter. However, the amount of oil pumped through the engine in that time is actually quite a bit, as flow rates in your engine oil are very high.