And AFC/AVC is not a replacement for any sort of ecu.. however, you could tune your fuel map, and possibly defeat the speed limiter with an AFC. Depending on what you buy.
AFC's are there to Fine tune and make mild adjustments to the Fuel curve already mapped in your ECU. These products are useless without an ecu. They also take a lot more tuning time. Although in comparison.. a JWT Ecu will run $600, whereas an S-AFC is like ~350?...
For places to buy stuff.. check out the Thread in the FAQ about online retailers.
On the tires - The TE-37's are Schweet!@ you could run 235's on them, but with a 40 height, they will hurt your ride quality a bit. The best bet is the 225's, but both will work.
For the LSD - I'm not totally sure if It'll work or not. You may need to verify that it has the same bolt pattern for the output shafts, but other than that I don't think there should be any difference's.
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