that is still rediculously conservative... 4/0 can hold WAY more than 230 amps, i think that 230 amps might even be able to go through 1/0.
but like i said before, those are petty much just suggestions, and it is always better to se bigger than required... if you want to see something really interesting i can dig up the chart of how much resistance the actual wire itself induces. its pretty interesting, alot more than you expect
Voltage drop is the key and has a definite proportional relationship to wire size. FWIW my '97 will momentarily draw +450A when starting. This is through 2ga wire and to a battery in the trunk. It is also routed through a 250A fuse. The amp draw will quickly drop to 150A and maintain that as long as I crank the engine.
There is no way the 130A alternator will put out that amperage on a continuous basis through the 6 ga wire that is OEM.
Probably one of the best things you can do to your car is increase the alternator to fuse box wire to 4 ga and increase the battery to starter wire to 2 ga, Negative cables should be increase to 2 ga also.