Hi,
I own an Octavia vRS with the 1.8 20v turbo engine. Ill state just now that I dont tow with it (but I want to!) but did have the car remapped approximately 3 years ago, and to be honest was purely a performance enhancement.
I went for a 'Revo' remap which is a fairly big company and was recommended by various other owners. The difference between 'stock' and 'performance' is pretty big, and under normal curcumstances I dont notice a difference in consumption, although I have seen the onboard computer reading 7mpg average for a 15 mile journey!
I accepted the risk that the Turbo probably wouldnt last as long (boost pressure increases) and that other parts would probably fail quicker such as clutch etc. There are also other considerations that much more technical people than myself make such as running cooler spark plugs with a smaller gap. (although this wouldnt apply to a diesel.)
The main reason i thought I would post here is as follows:
I also purchased a revo device that allows me to switch between stock and performance via the ODBII port. When travelling with a load (such as 4 passengers/going on holiday) i do tend to switch it to stock as my thinking is there is less 'potential' tourque to pass via the clutch and drivetrain, therefore lessing the stress, and indeed when I/We eventually save the money for a Tourer, I will employ the same routine - dont know whether this is absolute rubbish, but just my thoughts.
Also, when running in 'performance' mode, the car is not as smooth to drive. I find that the power delivery does peak a little as it comes on boost, a little more than stock. Dont get me wrong the delivery is still pretty linear, but its noticeable, enough to get the traction control going in 3rd over wet surfaces that have a 'yump' or two in them. Again, I have little to no towing experience, but I would presume that its probably favourable to be a smooth 'measured' tow as oppsed to 'peaky'?
I would imagine given that diesels tend to boost quite quickly, and they produce lots of tourque, it could actually be quite detrimental in a situation where you were towing off from a wet pitch, producing lots of wheelspin/traction control action?
I am of the understanding that Revo are quite favourable for the VAG range of cars, and a while ago they would do a 5 hour trial (a friend had this and it simply switches back to stock once the 5 hours of 'engine on' time has elapsed. Maybe a trip to a local Revo dealer for a discussion, maybe a trial and a test tow?
Apologies if this is a pointless ramble, but thought my experiences might help?
Cheers
Rob