VWDiesel.net The IDI, TDI, and mTDI source.
Engine Specific Info and Questions => IDI Engine => Topic started by: Smoker on May 11, 2015, 09:19:30 am
-
Getting ready to turbo my n/a 1.6.
I have
-vnt15 and downpipe
-alh and ahu intake manifolds to pick from... I also have a g60 mani that I want to use later, when I add an intercooler.
-oil return line
-oil supply line... For this, I have a hard line from an alh car that I reshaped to line up with the top of the oil filter housing. I'm assuming/hoping I can just drill and tap the top of it for the banjo bolt?
For now, I'm planning on using my original n/a pump, but I have a late mk2 pump with the anti-soot dealie or whatever that I'm eventually planning on resealing and swapping the ports.
I know I still need:
-boost piping kit
-boost and egt gauges
Any specific recommendations on this stuff? Where to buy? And am I missing anything? I'm hoping to do this with as little down time as possible.
-
What are you going to use to control the vanes?
-
Fixed position, although I need to do some more research on that.
-
Air filter/housing/piping?
Oil pan provisions for return line?
-
I'm on the oil pan provisions. Got a fitting that I'm having a tig guru buddy of mine graft in. As far as air filter, I have a generic "cold air" filter from an alh car I parted out, as well as a box full of random pipe/hose/clamps from parted out cars...
-
Ordered my gauges today. I think the only thing I'm missing is boost piping... Anyone have suggestions on that? Gotta be cheap!
-
You might want to upgrade the oil pump to 36mm gears as the turbo bearings consume a fair amount of oil. You're probably fine with 30mm gears, though, if you don't have the piston cooling oil jets.
-
If you have a stock 1.6 cylinder head, the intake ports are oval and the AHU/ALH manifolds you have "D" shaped ports and can leak at the head interface due to the profile mismatch no matter which gasket(s) you use. You might want to use the G60 manifold now, and I'd recommend at least a 2.25" exhaust system from the turbo back.
-
You need to come up with a plan for the CCV as well since it can no longer go into the manifold, it needs to be preturbo.
-
You need to come up with a plan for the CCV as well since it can no longer go into the manifold, it needs to be preturbo.
Good call, I hadn't thought of that... Suggestions?? Just plumb it into the intake tube between the air filter and turbo?
-
You need to come up with a plan for the CCV as well since it can no longer go into the manifold, it needs to be preturbo.
Good call, I hadn't thought of that... Suggestions?? Just plumb it into the intake tube between the air filter and turbo?
That's what I did on mine...
-
If you're going to use an intercooler, you may want to consider some sort of catch can system to minimize oiling of stuff upstream of combustion chamber.
-
If you're going to use an intercooler, you may want to consider some sort of catch can system to minimize oiling of stuff upstream of combustion chamber.
I'm of the opinion that oil in the intake tract is a good thing. It helps to catch any dust/dirt that makes it past the filter.
-
The oil counts as fuel too. It doesn't harm anything but people often seem to have a problem with it. VW and virtually all car makers seem to think it's fine.
-
Fixed position, although I need to do some more research on that.
Anyone have advice on this? I know plenty of people have done it, but for some reason my googling hasn't found me any real specifics on it.
-
It's because it isn't a logical thing to do. A fixed position that will give good low end boost will be restrictive. A fixed position that isn't restrictive won't give low end boost. Since there's no wastegate all the gasses have to go through the vanes regardless of what RPM and how much exhaust is coming out of your engine. High EMP at higher RPM becomes a concern as does overspeeding the turbo.
If you don't intend to use the vanes with some sort of control, be it mechanical or electronic, you would be MUCH better off selling the VNT and buying a wastegate turbo sized for your power goals and driving needs.
-
It's because it isn't a logical thing to do. A fixed position that will give good low end boost will be restrictive. A fixed position that isn't restrictive won't give low end boost. Since there's no wastegate all the gasses have to go through the vanes regardless of what RPM and how much exhaust is coming out of your engine. High EMP at higher RPM becomes a concern as does overspeeding the turbo.
If you don't intend to use the vanes with some sort of control, be it mechanical or electronic, you would be MUCH better off selling the VNT and buying a wastegate turbo sized for your power goals and driving needs.
I'm well aware of the cons. But I'm on a super tight budget, and I've heard more than one person claim that there's a "sweet spot" for a fixed position. They may be right, they may be wrong. I guess I'll have to go on a trial and error basis.
-
Keep in mind that I have almost zero dollars in this setup, which is about what I have to spend. I have to think that a fixed vane vnt has to be better than the 50 hp or whatever I was living with before...
-
I get the no-budget thing.
There will be a spot you can find with trial and error that will generally work for you. Your low end performance will suck, you'll have the equivalent of a cork in your exhaust at higher RPM but it will "work". The turbo may not last as long, but it will "work".
The yellow line in this graph is the vane position during a drive on my VNT (0=fully open, 100=fully closed) - there isn't really a 'sweet spot'. "Cruising" boost is around 4-5 PSI on my setup (graph is in kPa - 100 kPa = 14.7 PSI), depending on RPM that can be the vanes fully closed or it can be the vanes resting around 60%. With the pedal to the floor I'll hit about 30 PSI with the vanes anywhere from 40% to 20% depending on RPM. If I had them set at say "60%" all the time my turbo would explode absolutely 100% for sure. It would be 'safe' to have them at 20% but I'd have very little boost EXCEPT with the pedal to the floor at 4K RPM.
(https://c4.staticflickr.com/8/7680/17682213005_58b4d8e963_z.jpg)
If you have no budget, then you probably can't afford to replace the turbo if you blow it up during your trial and error period. So SELL it and use the proceeds to buy a wastegate turbo. You should come out about even, but have something that will last a long long long time.
You can also try building a mechanical VNT control system, there's a few versions lurking in the forum. That isn't particularly expensive, just time consuming.
-
Good info, thanks. I'm saving my pennies for a purchase from alcaid... Hopefully it won't take too long!