There is a torzen LSD I believe. I know the newer models come with one but I'm pretty sure torzen made one for the 08. A 295 would be more than enough rubber you'd have a hard time getting it to spin with both wheels locked. I have 295's on my sc with a 2JZGTE and in low boost (440 rwhp) it slips a little when I dump it around 2500 which is where it starts to make boost. It's a shame the stock rims aren't wider. I'm in the same boat as u I like the stock rims too much to change them.