Call me crazy but, KP39 on a non-pd?

So I've been keeping up with bencarr23's progress with his PD. It's really seeming like that KP39 is a solid turbo. I also recall hearing somewhere that dzljet switched to one as well. Is this turbo really capable of sustaining 20+PSI on a daily basis? I'm looking for a locally available alternative to the PD150. The turbo is the main thing holding me back from chiptuning. I want to get nice powerful programing, but don't wanna be replacing a turbo every year. That and the VNT actuator on my current turbo is on the way south. RC3 with a KP39 and my Sprint764s would seem to be a nice reliable setup for a ~150hp daily driver.

Anyone comment?

--Matt

Are talking about a stock PD 100 turbo? If so, it is not designed to withstand 20+ PSI sustained. I guess it is possible to try it. Be the first to prove everyone wrong. I love to do that as well. I would like to see th shafts in those to see what they look like. From what I've heard, they will not take serious boost. Just what I heard. Goes in one ear and out the next usually unless I try it my self. Good luck.

No, Dzljet was a Beta Tester/Buyer on the UPsolute Stage III kit that had a GT20 turbo on it. It's my understanding, folks were going nuts with the setup as the turbo outlet went straight up into the engine bay rather than down under the car which caused a really tight fit with intake and IC pipes. But the setup worked. It was feedback from a couple folks (not dzljet) who weren't very happy working the plumbing out that got Rene to change to the new T3 turbo or whatever it is. That's the story I've heard, don't know if it's 100% fact. I guess now, it fits better w/T3 but the turbo doesn't spool as good as the GT20. Or at least that's the impression I've gotten. I'm told this could be nothing more than installer error and I have to believe that could be true based on what I've seen in my time. I know this, Dzljet was up my way in June and he could eat my modded vnt eqpd TDI at will in any range with no spool issues.
The overall setup with injectors/mapping etc. on T3's may be at odds, to be honest, without driving one and testing one out for setup, boost leaks, install error stuff, I'd hesitate to pass judgement on it just yet. I'd love to see one!!

The KP is not supposed to have a cut shaft as I recall, I'll try to confirm this. I've been to Dzljet's and seen vnt 17's taken apart with cut shafts, I've also disassembled vnt 15 with similar looking shaft. So I know for sure the vnt's are all cut.
Even still, they should be good for 150K miles, they just get broke due to clogging of intake and resulting spool issues. Keep a clean system, run boost at about 18.5 max sustained and/or it would be really wise to keep temps down by a variety of methods. IC upgrade is a must IMO, 20 psi could be done daily but not for excessive amounts of time, particularly with the setup you want.

I won't get into chips, most know I try to stay nuetral there, but I believe regardless of tuner, the setup you want can be reliable within that range but you must make hardware changes. I guess it depends on overall power and how and when you want it delivered. I've driven RC and UP, I know which one I like but I'm aware that's my personal choice and I won't push it on others.

ok there are at least 2 people out there running 23 psi spike down to 20 then rise up to 23 in the higher rpms. right no wwith the larger injectors 18.5 is steady and i have seen 20 and hold. boost is not the prob. with these tb's . its heat. no sustained long hauls .and you should be fine . and i want 24 psi . i just need to talk jeff into doing it.

Surge line
The map width is limited on the left by the surge line. This is basically "stalling" of the air flow at the compressor inlet. With too small a volume flow and too high a pressure ratio, the flow can no longer adhere to the suction side of the blades, with the result that the discharge process is interrupted. The air flow through the compressor is reversed until a stable pressure ratio with positive volume flow rate is reached, the pressure builds up again and the cycle repeats. This flow instability continues at a fixed frequency and the resultant noise is known as "surging".




Choke line
The maximum centrifugal compressor volume flow rate is normally limited by the cross-section at the compressor inlet. When the flow at the wheel inlet reaches sonic velocity, no further flow rate increase is possible. The choke line can be recognised by the steeply descending speed lines at the right on the compressor map.

Surge line
The map width is limited on the left by the surge line. This is basically "stalling" of the air flow at the compressor inlet. With too small a volume flow and too high a pressure ratio, the flow can no longer adhere to the suction side of the blades, with the result that the discharge process is interrupted. The air flow through the compressor is reversed until a stable pressure ratio with positive volume flow rate is reached, the pressure builds up again and the cycle repeats. This flow instability continues at a fixed frequency and the resultant noise is known as "surging".



Choke line
The maximum centrifugal compressor volume flow rate is normally limited by the cross-section at the compressor inlet. When the flow at the wheel inlet reaches sonic velocity, no further flow rate increase is possible. The choke line can be recognised by the steeply descending speed lines at the right on the compressor map.

Click to expand...

Wow, someone's been doing some reading.

That's correct, to all those that want to understand what that means.. It means most vnt's seem to be blowing at startup/off the line, hence; from surging. This is the great danger of the vnt turbo's. Combine a clogged intake and lack of air that results with a turbo that's just shy of going into surge from the factory tune, turbo design and you've got the potential for a problem.

Choke or the "high end" is seen when that big cloud of black smoke comes out the tail pipe in the higher rpm's. Racing at 120 mph..not that anyone here would do that. This causes an increase in EGT's and is eventually what will melt seals and the result will be oil passing through casuing either a slow turbo destruction if this is done repeatedly but not for too long periods of time, where a long drag say up a mountain or a top speed run for several minutes would cause a catastophic meltdown, due to running the turbo at or beyond the "choke limit" for too long.

btw; the vnt's run at choke at about 4200 rpm's so it's really senseless and potentially destructive to try and run a TDI in that range.
Similarly, it's potentially destructive and has resulted in many a blown turbo (even stock) to place high throttle demand (hence; boost) at a low rpm.

This type of info should be in the fundamentals section.

So it's capable of more boost, but the additional boost is hot not so usable due to the high air temp? Would that be much of an issue at the 18-19psi? I think that's where RC3 runs. I'm thinking that the better shaft would at least be a good start. That and I believe that turbo is 1050C rated, so temps at reasonable power levels should be acceptable.

Anyone else comment?

--Matt

I'd like to see where the efficiency range of the 2 turbos falls. Technically, after a certain PSI, any turbo is goign to produce more heat than air pressure when it's out of its efficiency range.

The KP39, being a smaller turbo, should spool faster, but I have a hard time believign that it's efficient for a higher pressure than the VNT15. The only way I could believe that is if it's just a better design of a turbo or made of a higher quality material. If it has a bigger turbo shaft or is made of a material different than the VNT15, it may withstand more heat. Of course, that's a moot point if the turbo is inefficient at the pressure you want to run and hits the max temp too fast.

In either case, does it seem like that might be a good turbo to match to RC3? My actuator is worse by the day and I'm not able to remedy it so much anymore. RC3 runs what, 18psi?

--Matt

--Matt

the kp39 can handle it .