bv39a

bought this awhile back... appears to have a billet wheel but doesn't really look any larger than a vnt15...from my research it came from an industrial application such as a forklift...would it be an acceptable replacement for a vnt15? capable of any more ponies than the stock alh pressure inducer?

I was just looking these up for my BHW. They seem to be good for about 200hp, with near-stock spool.

in the passats, I guess they're almost plug and play, only needing the compressor outlet hose modified from what I can tell.

Dan99TDI said:

I was just looking these up for my BHW. They seem to be good for about 200hp, with near-stock spool.

in the passats, I guess they're almost plug and play, only needing the compressor outlet hose modified from what I can tell.

Click to expand...

this one is is configured for a transverse ve or pd...won't work at all on a BHW in a longitudinal application.

I'm pretty sure these are what's known as a "baby VNT17" in some circles.

Actually very comparable in size, max safely supported boost and response to the BHW's 1749VA.

Should be good for about 23 PSI safe, sustained boost (or about a pound short of a full on VNT17/GT1749VB) but thanks to the smaller 'wheels', it will still have the low end response like a VNT15.

Solid turbo for a daily driver to both get that extra boost while retaining low RPM response.

I believe Kerma uses this as the basis for their "S7" turbo as well, with an updated billet wheel maybe or some other kind of adjustment. Would have to ask them for the specifics.

The BV39 uses B-W's 'extended tip' technology, which is part of what allows them to safely support more boost while keeping the smaller wheels.

All around, solid turbo.

BV39 is more like GT14/GT15 territory. BV43 is most comparable in frame size to the GT17 series. The bottleneck will be in the turbine side, not compressor. Even the GTD1449VZ is used in the 184 HP TDI in the GTD and there is supposedly (if it's not a typo) an OEM GTC1459VZ used in the earlier CR170 GTD, PN 03L 253 010F / 785448-0003 (note the bigger compressor wheel for less rated power).

I have used it on a uk mk4 1.9 tdi 110 Bhp engine, spooled quicker than a gt1749va with good egt after a chip tune, the owner bought race 520 nozzles but never got them fitted...
As the boys said, bv43a is the turbo to go for in longitudinal engine or the small garrett cr turbo of 190 Bhp audi engine but expect boost creep...

Matt-98AHU said:

I'm pretty sure these are what's known as a "baby VNT17" in some circles.

Actually very comparable in size, max safely supported boost and response to the BHW's 1749VA.

Should be good for about 23 PSI safe, sustained boost (or about a pound short of a full on VNT17/GT1749VB) but thanks to the smaller 'wheels', it will still have the low end response like a VNT15.

Solid turbo for a daily driver to both get that extra boost while retaining low RPM response.

I believe Kerma uses this as the basis for their "S7" turbo as well, with an updated billet wheel maybe or some other kind of adjustment. Would have to ask them for the specifics.

The BV39 uses B-W's 'extended tip' technology, which is part of what allows them to safely support more boost while keeping the smaller wheels.

All around, solid turbo.

Click to expand...

I have one installed on my MK IV sedan which Matt services. I can tell you from personal experience that it spoils faster than a VNT17 however doesn't have the top end power. My current set-up is PP764, PD130/150 TIP and RC3 tune. While Jeff at RocketChip prefers Garrett turbos, I can say that my current turbo is more to my liking due to my driving style. After Jeff suggeested to make an adjustment to the actuator I have found that the car is even more responsive than with the VNT 17.

The GT17 family have 43mm turbines, corresponding to BV43. GT14 have 39mm like the BV39. GT15 have 41mm.

If this helps, I put a direct replacement Borg Warner turbo on Donna‘s car about four years ago. The body is slightly smaller than the VNT 15, so I think it probably is a 39 mm. The car has a mild RC2 tune on it and whatever injectors Peter sold me when I later did the hot swap with ID parts, again mild upgrade. Donna grannies it, she never winds it out through the gears but she will cruise 80-85mph down the highway. She consistently gets between 50 and 52mpg summer, 47-49 winter. I take it for a ride when I service it every 10k and It still spools quickly and I have to backpedal second gear to hook up the tires if I punch it at 1200 rpm. Pulls great on the highway and through the gears. Good drivability for normal transportation and more than adequate for getting on the highway or passing at cruising speed.