I've blocked off my BOV with a bit of reinforced hydraulic hose I had lying around and a 3/8" to 1/4" socket adapter and some jubilee clips.

The BOV vented to the intake pipe so I fitted a breather filter to were it connected to the intake pipe.

Anyone know of a better/neater solution?

Its a SB 1.6 IDI TD engine.

Cheers

No need for the breather filter on the blow off valve outlet.  It's just a feature to protect the engine from overboost in the event of a stuck closed wastegate, so it never actually lets air flow through it when things are working the way they should.

Why would overboost really be a bad thing on a diesel? Wouldn't running infinite boost just continue to cool egt's and increase combustion efficiency, or would the LDA still supply enough fuel to burn up the engine? It's my understanding that they eliminated the pop valve on the Eco Diesel intake which makes me assume that this has to do with the latter.

Actually boost = heat.  And the turbine creates a lot of heat, because the exhaust gases are compressing as well.

That's not exactly how I've understood things. Yes, with a gas engine running more boost will create detonation after a certain point due to increased cylinder pressures and decreased air density due to heat. Running more boost when more fuel isn't available will increase heat which can cause engine damage regardless of detonation.

When you consider your standard diesel compression check ought to yeild results in the 400+ psi range, it seems like a drop in the bucket to add a little extra boost. But I suppose in theory if we run 1 bar of boost we effectively double cylinder pressures. Of course this will lessen as boost increases due to the heat generated by compressing the air.

From everything I've read, tuning a diesel is more like an excercise in chasing your tail. Ultimately, excess fuel will melt pistons, not boost. With a lean burn engine like this, adding boost will essentially lean the engine out, or reduce engine load - which ultimately reduces EGT's.

If I'm overlooking something , feel free to chime in  

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Why would overboost really be a bad thing on a diesel? Wouldn't running infinite boost just continue to cool egt's and increase combustion efficiency

It would, until the physical limits of the turbo are reached and the compressor wheel bursts due to excessive speed. The other enemy is cylinder pressure. As you said, doubling the intake pressure will double the cylinder pressure. This will catch up to you at some point.

 Boost is  limited to a safe level on later models by underfueling them. No fuel = no heat = no boost. I don't think a  stock 1.9TD with the wastegate tied shut could really hurt itself.

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If I'm overlooking something , feel free to chime in

 You've pretty much got it, The only limit to the amount of power you can make is the physical strength/heat resistance of the parts. You can compound turbo's to easily obtain 70psi of boost. If you can get the rods, pistons and head gasket to hold then you could make some huge power.

I haven't actually heard of much of an issue with the compressor wheel coming apart. As Deo stated, they were running over 35 psi on the stock turbo.

Gotcha, thanks for the clarification.  

Have you seen this cross-section diagram of the BOV?


I found that the stock range of adjustment maxxes out at an operating pressure of about 14psi (a little under 1 bar), which doesn't sound like enough for your needs.  I have heard that if you unscrew the adjuster completely, you can install a shim behind it (going between the threaded adjuster and the spring that is behind the adjuster) that can cause it to raise it's operating pressure higher than the stock adjustment range, or if the shim is thick enough, lock the position of the valve completely closed (accomplishing the same thing as capping the air outlet.)

Stock intercooled 1.6lTD... nice motor... you know those weren't available in north america.  drool!

I haven't actually heard of much of an issue with the compressor wheel coming apart. As Deo stated, they were running over 35 psi on the stock turbo.

So why doesn't VW run all there diesels at 35 psi boost? At that boost level the 1.6TD could have made well over 150hp and still got 50mpg. Also, nothing improves emissions performance like boost, it helps with NOX, particulate, hydrocarbons, everything. If it can be done with the stock turbo, stock internals and with 100000mile reliability whats the holdup? In fact, why the hell am I not doing this? I had no clue that my 200+hp 1.9TD was just a chopped wastegate hose away...

What size of plug do you need?  VW sells a 5/8" rubber antifreeze cap for about a buck.  It is like a rubber thimble that goes onto the metal coolant hose...covers the connection for the oil cooler if you don't have the turbo.  My rad cap keeps about 25PSI in the system so it ought to be sturdy enough.

Steve

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I haven't actually heard of much of an issue with the compressor wheel coming apart. As Deo stated, they were running over 35 psi on the stock turbo.

So why doesn't VW run all there diesels at 35 psi boost? At that boost level the 1.6TD could have made well over 150hp and still got 50mpg. Also, nothing improves emissions performance like boost, it helps with NOX, particulate, hydrocarbons, everything. If it can be done with the stock turbo, stock internals and with 100000mile reliability whats the holdup? In fact, why the hell am I not doing this? I had no clue that my 200+hp 1.9TD was just a chopped wastegate hose away...

I don't know what world of magically exploding turbos you come from, but around here they just wear out faster and start to smoke. I think it's pretty damn obvious why vw didn't have cars running 35psi from the factory, that doesn't mean you can't do it. My Gas Rabbit makes almost triple the stock power output.....sure VW didn't do it from the factory, but I did it anyways.