Hi all I own vw caddy/ felicia pickup with the 1.9 sdi engine but want to try make it bit quicker has anyone tried to fit a turbo onto the sdi engine or whats my best option engines got quite low mileage {92k} so would be a shame to swap it out. Thanks. 

Yes you can turbo them, there are a few guys on here that have done it, try contacting the member called rolo on here, he has don it and I think felicia16v has done it too, it involves changing the manifolds, injectors and injection pump so it's not a job for a novice.

Are there not any issues with the increase of boost on what started out as a high compression engine?

It's not such a big issue with diesels, you could fit lower compression pistons from a turbo Diesel engine if you wanted to, but as long as you keep the boost levels sensible it will be ok.

That would be the trouble if I were to do it I'd end up going made on boost and blowing the thing to bits :-D surely you'd get a little performance from tweaking the fuel pump up slightly? 

It's not the injection pump that is the limiting factory nor the injectors, it's more to do with the engines ability to burn all the fuel completely, you can make it crank out virtually as much fuel as you like to the point where it just just chucks out black smoke from the exhaust if you make a few adjustments to the pump, which is just unburnt fuel through lack of air, then you just need to figure out a way of adding air, turbocharging anybody?

it would be wise to fit an injection pump from a turbo deisel engine which is designed to advance the injection event as boost rises too, something like from a land rover tdi, I believe these are a straight swap on these engines.

supercharging has always been my favourite approach but that has parasitic losses associated with it due to it's mechanical nature, turbocharging is by far the most efficient way of adding air because it's recycling the waste energy from the exhaust gas to drive the turbine.

The other options could be using nitrous oxide and/or propane injection but that is reserved for much more highly engineered and higher stressed solutions.