[The Mighty Red]

Got quoted $440 to have a 4.11 diff ratio put in the XR (LSD)today and i also get to keep the 3.45 thats in it now,
I thought this is a fairly resonable price *( i was expecting it to be more)
Is It around the mark?

Is there any short falls with this mod that i should know about before i go ahead and do it.

The reason for this mod is purely performanced based, i am looking to get more low down acceleration,

Will i need a chip to run this mod?, meant to ask the mechanic but i forgot.
Mechanic says it wont change the speedo reading , is this correct?

Thanks in advance Gary