Ball Bearing Turbo experiences- want to hear from you

Spool is made by right choice of turbocharger compressor and turbine wheels and housings. You clean the smoke by adjusting your afc-valve in mechanicals and smoke limiter maps in electronic engines. You won't even notice the difference in spool up time between bb and non bb charger, it's maybe 1/10 th of a second from no boost to say 2 bars of boost. But bb can take more punishment from high boost but it's service interval is shorter than journal bearing.

Oh, and remember, big turbo never spools like smaller one.

 

Only experience I had with a BB turbo was on a pickup used for sled pulling, didn't even last one run. It was a Turbonetics.

 

The first problem was it was a Turbonetics. The only thing worse than their turbos is the customer service.

I've run a couple BB Garretts on Big Cams with good results. They do spool quick, but they are usually 2x the price of a similar spec'd journal bearing turbo. The real benefit of the BB turbo isn't so much the spoolup as it is their durability. A BB will take a tremendous amount thrust load, so you can overspool them without hurting them and they don't require as much oil flow.

 

Twins or compounding turbos may be able to be set up to spool quicker. I dont think you'd see a huge change in spool time between a plain bearing and ball bearing turbo, there would be an improvment but I dont think it would be much.

I think this assumption comes from smaller petrol engines where ball bearing turbos do spool faster but small turbochargers have very little weight so the bearing drag consumes a considerable percentage of the energy required to get the turbo spinnings whereas with a large frame turbo off a larger diesel the weight of the turbos rotating assemlby is much larger but the bearing drag is not much more than a small turbo so by reducing the bearing drag wont see as much of a gain as most of the energy required to get the turbo spinning is for trying to get the weight of the rotating assembly moving.
My opinion, not proven facts.

 

It would be nice to know what Michigan stage 5 actually is, wheel sizes, housing a/r etc. to recommend a better turbo.

Change back to stock manifold and fit those sleeves back if you have removed them.

 

Here are the specs on a B/W318883. Com 86.4 ind 120.3 exh
Turbine 109.7 ind 99.1 exh, with a 1.60 AR. twin scroll housing, seems to do a good job, FWIW.

 

I run a GT4718R ball bearing (non wastegated) turbo and think its perfect for what I want BUT I am no expert.
What I did was put the turbo on my C-16 with no other mods done and run it like that for 2 weeks,it was very laggy but boosted well and kept EGTs down by 150*C and IMO it did spool faster.
When I added the larger injectors it removed any lag and boosted to 50psi you did have to watch the EGTs and turbo surge under 1400rpm but have always run it at 1600rpm also EGTs fell even more with the bigger injectors at higher rpm's.
A down side to the BB turbo is that it only flows about 2 liters of oil a min compared to a journal of 5 liters so the oil is not cooling the shaft the same I have been told to direct some air flow onto the cooling fins on the center housing to help the turbo last.
I have not done the bigger manifold and turbo housing in fact the opposite the BB turbo has a exhaust housing A/R 1.23 where the stock one is 1.39 (I think) I will change the manifold to a coated one from PDI though.
Talking to Garrett over here the GT4718R will handle 50psi no problems and I found I can change the exhaust housing to a dual entry with a A/R 1.37 (about) this I have been told will make it better at lower rpm's.
The turbo gets a huge work out over here with our terrain (lots of hills) and CAT recommends the turbo on C-15/C-16 gets changed at 500k km if it lasts that long.
The CAT agents over here said they would love to run BB turbo's on all there engines but would cost far too much.

 

Send me your e-mail address and I can send you some pics of the turbo on the bench and on the engine.
Also its worth comparing the shaft size on a BB compared to a stock C-16 turbo looks like the BBs is twice the size.