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My buddy is starting to get to the point where he can play with the vanes on his Powerstroke turbo. The little bit of experimentation is quite impressive. 3000 rpm at half throttle was producing 10 psi at 80% duty cycle on the vanes. Basically, this thing will produce insane amounts of boost at a ridiculously low rpm for a large framed Garrett that has the compressor wheel of a GT4082.


http://www.youtube.com/watch?v=Mf5qTMBlRno

Holy Moly!! I was starring at that temp gauge not even really paying attention to the boost and RPM's going crazy!! Then I realized your put a bubble staying it was broken. Wow, that was scary lol.

Make a thread "Heart Stopping SS boost vid"

He just started playing with the vanes. With the vanes fully open it hits at 5k, but stays spooled when his built (rigoli style) auto shifts to 4500.


I'm just really excited to see how this plays out. He needs to fully tune the car (Hydra) with the vanes open, and slowly close them down at lower rpm's, and tune for it.

If this works out, I'll be converting next winter...

It's funny how the exhaust gets MUCH quieter when the vanes close. With the vanes open the car is very loud, since there is only two resonators and no muffler.

Nice turbo!

I have a Garrett VNT that is the equivilent of a gt28 which is run off of vacumn... Not sure exactly how its gonna work, but we are going to run it with E85 to keep the exhaust cool.

that looks fun!! gotta love turbos lol. plans for a 5mt?

Vacuum? I could see it referencing boost and opening the vanes as the boost comes on. Interesting though.

I think the Holset variable geometry turbo for diesels is electronic. A stepper motor or something like that.

Yeah, vacuum. I had no idea it was VNT till I opened it up. Its the turbo on the diesal jeeps.....

Vacuum its closed, boost opens it up.... (or vice versa)...

Hi all
I am the owner of this car in the video clip above.

Them smaller VNT's use a vacuum system with a vac pump and a solenoid that is independent of the boost pressure. it uses sensors and ecu to control boost. On the dodge/mercedes sprinter vans the ecu can de-spool the turbo just before the transmission shifts. its kind of funny hearing that happen while your driving it

But u can use a normal wastegate actuator and boost controller to move the vanes.

the gt3782 vnt uses oil pressure and a little hydraulic cylinder and a solenoid to move the vanes

there is also a larger gt42 size vnt on series 60 detroit diesels that uses pressure from the air brake system to move the vanes.

You actually made a post, hooray!

This man knows his stuff.....

I uploaded another video

I was doing some more testing and shot a quick video of me brake torqueing it. I think i need a lower stall converter.

http://www.youtube.com/watch?v=zKV-kDFNl4c

Keep in mind that this turbo is a bit larger than a 35R. they spool at around 4600 Rpm give or take.

later

Well...I think I now know what my Audi will be getting...


How much was that sucker? And I assume it's off of a 6 liter?

I see them for $400-500 or so used. And you are correct in that they are off the 6 liter.


The trick is being able to control the vanes. You can get by with a very nice electronic boost controller to run the Ford solenoid, but a standalone with a general purpose 3D PWM output is better. A 4D map would be tits, so you could also reference load.

Good stuff. Can you take a video comparing fully open vanes to controlled vanes building boost?

We might do some tuning tonight, and can take some video. With the vanes fully open, it makes about 20psi at 5k rpm.

We did do a little tuning tonight and here are the results

http://www.youtube.com/watch?v=7GdY55GfGus a nice little 2nd and 3rd gear pull. the tcc was locked in 2nd gear untill i shifted

http://www.youtube.com/watch?v=yvCQoaMttmM a full brake torque launch


There are more spoolup gains to be had with more tweeking.

Later

Nice!

Looks like fun!

What's the noise before the 1-2 shift? Torque converter?

Derek was shifting it manually. He's using a SVX TCU since you can hold the gear as long as you want, and the SS TCU shifts at 6500 no matter what. The SVX TCU requires a "normal" TPS though, so it won't work with an SS ECU.

We think the torque converter clutch started to slip as well. It didn't like that much early boost in third gear with a hot tranny.


What was really interesting is how sensitive the motor was to moving the vanes. A matter of 5% duty cycle means the difference between not spooling that turbo quickly and choking the motor. We have a lot more work to do. This looks really promising though. I might have to take the plunge next winter. I'll need a twin disk clutch though With an hour and a half of work, this thing is spooling faster than my GT2871R 56T. That hurts.


Now for some LSD's, lol. Dunlop Z1 Star Specs shouldn't roast that long....

93forestpearl wrote: but a standalone with a general purpose 3D PWM output is better.

Oh good...my standalone has that

Apparently the Ford solenoid on the turbo is problematic, and might be why it was so sensative. Today the output transistor on the Hydra cooked and is shorted.

Hopefully just a new transistor will fix it, and a new solenoid.