I am looking to buy a 2001/02 A4 1.9/2.5 TDI Quattro ( I fancy the Quattro partly for the improved road holding and partly as I have been told it will cope with the modifications I want to do better - apparently once you start getting into higher BHP figures front wheel drive only starts to spin as it cant cope with the power???) with a view to doing some mild(ish) tuning. I would appreciate any comments or opinions as well as advice from all forum members. The list below is what I am considering.

1. Probably the most obvious choice - A remap of the ECU, comments & advice welcome on best companies please ( I read there is a thread on here with opinions / poll on the best companies - please can someone post a link). Also is there a mod available that lets you choose from a number of different programs e.g. Economy, Normal and sport or +20 BHP / +40 BHP / +60BHP as an example?

2. I read that increase the nozzle / injector sizes is a cheap and efficient power upgrade. Apparently a good idea if you do a remap, again comments welcome.

3. Upgrading the turbo. I have seen a company online, JBS, who seem to do a lot for VAG cars, I have read its possible to get over 200 BHP from upgrading the turbo on a standard 1.9 TDI 130 BHP engine. I want to know if this is the gain simply from changing the turbo or is this also including the remap? advice on other suppliers also welcomed

4. LPG Fumigation system. I read and understand that by adding LPG fumigation (the Diesel world equivalent of NOS) you not only gain BHP but improve MPG / efficiency by improving the amount of diesel actually burnt. Typically improving efficiency from around 75% upto 90%. Is this true and could it work in conjunction with all the above? I also believe this actually cleans the engine too?? Can this mod improve MPG as well or only give a power boost?

I also just read an impressive review about a company call Allard Motor Co. who tuned an A3 2.0 TDI to 317 BHP, does anyone know if they are any good?

Finally I am still trying to find some reviews / road tests online of some modded TDI's Audi or VW I am not too bothered, I just want to get an idea of what effect the above modifications might have on 0-60 times and top speeds as well as MPG efficiency figures. Most of the reviews (and its not that many) that I have found seem to concerntrate on bragging about the BHP and Torque, but I want to know what this translates to on the open roads.

Looking forward to your comments