I don't think the 2013 is going to do much for the Si. I had an 08 and I felt like it was the best year. I don't care for the 09+ honeycomb change and the 12 body change looks blah from the back. Front isn't bad though.
However, using the K24Z7 is vastly underwhelming. Sure, you get some more torque off the line, but the numbers are misleading because you're only going up to 7k rpm. So while you're shifting at 7k, the older models are still high in their band until 8.6k. It all washes out in the end. Not to mention you lose the fun of revving up that high. Then you have the new integrated exhaust manifold which makes doing performance mods a royal pain. In my opinion, the K20 Si's are still far superior to the 2012 model.
Coming from a tuned K20 Si, I still love the feel of the FR-S over it, and then it's also RWD. I've already had fun on a good few corners and needless say.. the car embarrasses me. I feel like it's saying "hah, is that all you got for me?!
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