Dutra Duals

Not bein a smartass, but you're asking us about parts YOU have. Those things are fairly new. I don't know anybody who has them installed. The older ones that Doug cast himself, yes, but those required grinding or machining to finish, so they are not a good comparison to what you have. It's not difficult to figure out. You have the car, the engine and the parts. Look at it as a jigsaw puzzle and have at it.