I have a few questions. Which UDP are the best? I need to retain my stock belt. What spark plugs work best with the MSD coil pack and wires? Also what would be a better investment a BORLA cat-back or the R/T HFC? Thanks
I'll answer the easy one.
R/T > Borla. 
OK, if you don't get the "symbol"...
R/T is greater than/way better than/a must have, over the Borla. 
While the Borla sounds exceptionally nice, you might get all of 1-2hp (if that) out of it.
Now the R/T on the other hand is not only a great power adder,
it also sounds excellent with the stock exhaust.
I would most likely have one, if it didn't bump me up to the Prepared classes in SCCA. 
The FRPP UDP is a Esslinger setup which is probably the best. Keep in mind one thing, you really will need a tuner to kick up the idle to compensate for the slow moving alt pulley. I would rather have the borla myself. I have had three systems and love the Borla far more than either the MBRP or MagnaFlow. I havent seen or used the other you asked about.
hey guys thanks for the info i didnt think that the pulleys would bring down the idle that much to where i would need a tune but now i know, i was leaning towards the R/T but wanted a little more feedback from people that have either or both, but what about the spark plugs any suggestions. thanks again  [thumb]
Just a clarification, the idle doesn't come down with the pulley. Because of the smaller CRANK pulley, the ratios change, making the Alternator pulley turn more slowly. To bring the ALT speed back up to normal range at idle, the idle must be raised a bit.