scorke

iTrader: (18)

Yessir, BW makes good stuff, my roomate from school works for them, its a shame they aren't that big in the aftermarket industry yet, but that will come in time with these AirWerks bits.

Scorke

Ted B

iTrader: (6)

My primary concern about the new BW items isn't the power potential, but the transient response of the thrust bearing arrangement as opposed to the Garrett BB. Also, I am a little unclear as to how the physical size of the BW pieces compares to the Garrett turbos of similar power potential.

MR Turco

iTrader: (16)

Good information in this thread.

scorke

iTrader: (18)

From what I have been told (not seen) the BW's way of combatting that is aero without BB is competitive sometimes better in the department of transient response. I do not really believe it either but there is lots of support for them in the drag community right now.

Scorke

hokiruu

iTrader: (19)

Yes, from the little useful (but ever increasing) information I have found on the BW's, their ability to spool up relatively close to the Garrett DBB turbos for a journal bearing turbo is in their wheel design, especially the extended tip models. Did someone say HTA?
I am curious how a TS BW would compare to a single scroll HTA-modded GT turbo of similar size. I am willing to believe that transient response would still be superior in the TS, but in terms of similarly loaded spool? Hmmm...

scorke

iTrader: (18)

It would be much better in both regards, transient response of TS vs OS is the main benefit!!!

Scorke

EvoDan2004

iTrader: (94)

it would be nice to see a ''TURBO ONLY SWAP'' comparison of the gt4088r turbo vs a BW turbo in the same size.... look at spoolup and mod/topend.

COL Knock

The twin scroll design widens the power range so it makes sense for the power levels at higher rpm when compared to something similar with single vane.

The only drawback I believe with the red is the internal WG's harmful influence on flow.

EvolutionBoy67

Geoff,

how would you compare the BW T4 S360 to a T4 TS GT35R with your kit on the EVO? I know that a lot of the supra guys are now starting to use BW turbos and the honda guys have been having great success with them.

hokiruu

iTrader: (19)

... as are STR4 guys...

Geoff Raicer

iTrader: (7)

i understand your concerns re transient response on a journal bearing turbo, however ive been impressed by everything we've seen from BWTS's new generation of airwerks turbochargers. The quality of their engineering dept and data is second to none, and i believe their latest generation of turbochargers will back that up. The head guy over there says ball bearings dont offer any benefits on these new turbos becuase they have refined the journal bearing system and the wheel aero so well. who knows whats true, once we can start testing we'll know a bit more. so far all the Garrett vs BW 42R has been controversial. the low 9 sec hondas are all running the BW now tho, 4G63 seem mostly 42R some are starting to switch over..

regarding the comparison to garretts, its actually really easy to compare sizes -

Garrett T2 = BWTS S100
Garrett T3 = BWTS S200
Garrett T4 = BWTS S300
Garrett T6 = BWTS S400

the new turbo nomenclature will be like this:

BW TS300 83/75 .91 - this is a Twinscroll S300 (T4) turbo with an 83mm exducer compressor and 75mm inducer turbine in a .91 a/r

we need to update our site with this new nomenclature sorry its outdated

id love to give you an answer, but we're waiting on 1 coupler... well be installing it on a 540hp stock engine evo9 test car which currently has our TS35R on it. sean ivey will tune it on his dyno hopefully in the next week or so. Anyone that is going to be at englishtown, NJ this weekend for the race can check the car out, it will be in our booth.

we'll have 35R vs S300 83-75 (aka 360-35) results on the evo9 first, but im really most excited to test the S300 91-82 (aka 366-40R) vs 35R vs 40R. that is going to be the interesting one

not only are these turbos very affordable, they have huge dia shafts and beefy bearing structures are easy to get parts for and easy to rebuild yourself. if you really do want it in a BB, it can be converted by a couple shops but IMO i dont see it being worth the effort and cost.


their engineers tell me they simply can not retain the durability they need with ball bearing center sections. their journal bearing system is very simple and very beefy. if you put the BW turbo next to a garrett turbo, the difference in center section volume and corresponding oil volume is drastic. Also they do 2 simple things to ensure excellent spoolup and response:

1) almost all of the new turbos are twinscroll
2) all of the turbos have conservative compressor:turbine ratios in the 1.10-1.14 range. no turbine efficiency robbing mismatches!

and cost


you can vent the internal wastegate to atmoshere with a custom o2 housing. the only drawback I believe is that the turbine housing is much too small

hokiruu

iTrader: (19)

Excellent info Geoff. Thanks for taking the time to address all those questions.