Project 440DD

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If you're going to run stock wheels on it I recommend 51 1/2 in. That's flange to flange on the housing.
I built mine with 52 and 5/8 to go under a Duster or Dart. But remenber using the wider brakes eats up an inch.
yeah, I'll be running 18s to clear the suspension stuff of the watts set up.