Editing a GT5 Save?

Hey,

So recently I've been playing GT5 and I've been wondering.. is it possible to edit the save?

I don't want to unlock every car, every track etc. but it would be nice to add a car or two to my current save, cars that I can't afford at the present time.

Obviously people can't gift me them due to the lack of PSN, and as far as I know there is no other way to gain cars, so I was wondering, perhaps its possible to edit the save?

Has anyone tried to edit the save before, to unlock things or alter your levels etc?

Hopefully someone can help me out, hey.

its proberly possable to do what you are asking.

I know of some one who recived a fully unlocked version of GT5 that he won in a comp. and Kaz the developer signed the disk.
he has access to every car/track/ and car upgrade in the game. but he can no longer gift any of they cars.
before the update that blocked gifting of cars above a set amount of money, he gifted a friend of mine several F1 cars

but if its possable to hack the save im sure there is some server side checking ;) to prevent cheeting online.

i doubt theres a way to hex edit the save values without corrupting the save
normally is another user save with the param.sfo changed to match the console id