Putting a VNT 15 on a Rabbit

Upgrades to the 1.5, 1.6 and 1.9 engines that make them go farther or faster
Fatmobile
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Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Before I can put the VNT in the car I need to put the EGT probe in.
To put the EGT probe in I had to remove the center section and look inside the manifold to see what I was drilling into and find the center of the airstream.
I had a real hard time seperating the turbo from the manifold. The bolts came out easily. Finally got it apart today and found 3 torx screws. I managed to get them out without breaking them.
Everything came apart, I got a look inside and found a good place for the probe.
It got too dark for good pictures.
But I'm excited, clean it up and stick it back together and it's ready to put in the car so I can plumb oil/air lines and exhaust for it.

I have heim joints for it now and the connections look much better.
I noticed that when you close the vanes for more power the pivot point is already acting against the spring without any boost.
When opening the vanes the pivot is pushing hard against the spring stop giving it a solid pivot point when it counts; reducing boost.
Making sure the vanes can be opened, even with no boost.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Here's a crappy pic of the probe installed:
imageshack sucks
Image

I was trying to show how it sits in the exhaust flow but it's hard enough to see without the camera.

The manifolds are all cleaned up,..
and put back together.
But the exhaust manifold isn't installed yet,...
a couple studs came out when I took the old exhaust manifold off and will have to be seperated from the nut and reinstalled before it can be mounted.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Here's another picture of the egr blockoff plate:
Image
I had to tap another hole because the factory hole was too close to the area that got ground off for clearance with the intake.

It's also another view of the egt probe fitting if you look close.

Update: I put the EGT probe on the other side now, the driver's side.
Because having the EGT probe, oil line and controls on the same side was getting crowded.
And I send the wires toward the driver's side anyway.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

I pulled a 1.5 from the car one of these is going into. The owner suggested I use it as a jig to make the downpipe.
So I used it.
This photo is to show the brackets that will be needed to support the downpipe and
that support hole on the turbo won't need a long bracket to support it,... it's not far from the block.
Image

The downpipe went together fairly easily. The turbo is far enough to the right that the it didn't need much of a curve to get away from the shifter.
imageshack sucks
Image
I switched to a digi2 intake because it draws air from the passenger side.
Look how nicely it leans to the left so the turbo can feed it without running hose all the way around it.
If it gets an intercooler I'll switch back to the Rabbit CIS intake.
Shifter clearance:
imageshack sucks
Image
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
hagar
Hillbilly Tuner
Posts: 2424
Joined: Sat Mar 11, 2006 10:11 am
Location: Near Lund B.C. Kanada.

IDI Performance.

Post by hagar »

IDI Performance Upgrades


Lets say that I found a Turbo like that in Duckling's trunk , and her turbo crapped out EH would I use it if it was in good shape ? YES.

Now since I am mostly after lots of BOOST at low fuel flow. , here is what I would do.

The deflector vanes are easy to operate manually while driving I would move them for MAX pressure and lock them there.

Looks like Andrew did a fine stab at getting them working automatically. IMHO that is one difficult task. Oh I am all for it , don't get me wrong..

Ask any American what is understood by improving performance , bet the answer will be more POWER.

Ask a European and the answer will be more Smileage yes more Km/Litre.

Using MB nozzles ? why not just turn the full load stop screw in ? . I go the other way smaller hole 193 and higher POP pressure. (works for me) 76 MPG Imp every day.

hagar.
rabbit_man
Turbo Charger
Posts: 274
Joined: Fri Mar 28, 2008 12:45 pm
Location: Alaska

Re: IDI Performance.

Post by rabbit_man »

hagar wrote:IDI Performance Upgrades


Lets say that I found a Turbo like that in Duckling's trunk , and her turbo crapped out EH would I use it if it was in good shape ? YES.

Now since I am mostly after lots of BOOST at low fuel flow. , here is what I would do.

The deflector vanes are easy to operate manually while driving I would move them for MAX pressure and lock them there.

hagar.
I think if you did that the turbo would go boom. :? Plus exhaust manifold pressure would probably be super high and not help mileage at all.

With my setup I can move the vanes to max pressure and get almost 10psi by revving it in neutral, driving down the road like that would spin the turbo really hard.
Fatmobile
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Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Yeah, it doesn't make sense to have a VNT set to max. Even when really working it.
Too easy to overpressure/overwork it.
It also wastes energy by creating backpressure during low RPMs.
It holds gasses back that were meant to easily and efficiently go around the turbine.
It is looking so great. I should have taken a picture when the turbo was connected to the intake on the "jig" engine.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
hagar
Hillbilly Tuner
Posts: 2424
Joined: Sat Mar 11, 2006 10:11 am
Location: Near Lund B.C. Kanada.

IDI Performance.

Post by hagar »

Are you guys forgetting that "Duckling" is "Hillbilly-TUNED" ?.

Nothing can go BOOM , now it may be that her maximum is different from you POWER hogs. .And since I never been so lucky in the trunk . ergo I never operated one...

The reason from VW to make such an expensive design ,is to make the turbo more efficient across the pressure and RPM band. IMHO.

hagar.
rabbit_man
Turbo Charger
Posts: 274
Joined: Fri Mar 28, 2008 12:45 pm
Location: Alaska

Post by rabbit_man »

How's your project coming along? :)
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

It should be running by the end of this weekend.
I have some pics in the camera,.. but it's not nearby.
Getting real close :)
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
rabbit_man
Turbo Charger
Posts: 274
Joined: Fri Mar 28, 2008 12:45 pm
Location: Alaska

Post by rabbit_man »

Fatmobile wrote:It should be running by the end of this weekend.
I have some pics in the camera,.. but it's not nearby.
Getting real close :)
NICE!! I hope your's works out better than mine did. :D
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Yeah,
Me too. :)
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Head is in place and snugged down with head studs.
Went to put the turbo on and the studs were too short for the special exhaust manifold nuts and washers.
Maybe I screwed them in deeper than needed and can back them out a few turns.
I heard 6 threads is minimum.

Maybe I have some longer ones around.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

OK, it's running,..
holding it's coolant.
Temp gauge is working
Radiator fan is working.
VWcaddy headlight relays are working bright,. all lights are working, actually haven't checked the plate lights yet.

I can rev it and get over 5psi of boost while sitting still.
I haven't driven it around the block yet.
This isn't my car, it's a 1.6 in a '79 German Rabbit body. I just found a front licence plate bracket,.. the holes are closer than most because it's Early?/German?
That's all that's keeping me from test driving it.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
Fatmobile
Global Moderator
Posts: 7564
Joined: Wed Oct 30, 2002 10:28 pm
Location: north central Iowa

Post by Fatmobile »

Oh, yeah, NAPA had longer studs,.. for about $1.89 each :shock:
Little stud $1.89 ??? ouch.

I couldn't sleep without driving it around the block.
License plate holder on, I didn't have to mess with the plate lights they work great.
Took it around the block, shifter can't hit 1st without pushing down for reverse so it's went right back up on the ramps after the ride.
I haven't floored it yet but goosed it a little and got 1 psi boost going down the street.
Seems like there is alot of hissing noise. I'm not sure if it's air passing through the exhaust or whistleing through the long runner intake.
I'm going to line the front tires up best I can, then taking it to town for an alignment.
'91 Golf gasser converted to a 12mm pump, M-TDI.
'84 1.6TD Rabbit with a VNT-15 turbo, still setup to run on vegetable oil.
'84 GTI with 1.7TD pistons and intercooled.
2003 TDI wagon
2000 TDI Jetta.
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