I am wanting to run a 14" magnapack, 2 y pipes (one from engine and 1 for a dual exit) and 2 4x18" 45d tips out the back. which one of these y pipes will work best for me? what is the difference in the pipes since there is price difference.

http://www.summitracing.com/parts/MPE-10733/

http://www.summitracing.com/parts/MPE-10768/

 

The only difference is the way the 2 outlets exit. The second one you posted will work best for you.

 

thanks! i was leaning towards that one to begin with. would i be ok keeping the stock y pipe from the engine? or would it be best (performance and sound wise) to swap it out?

 

^ A magnaflow Y at the engine may make a slight difference, but not worth spending the cash on it, unless your wanting to go to a 3" mid pipe. In this case you will want to order a 2.5"IN 3"OUT Y pipe.

 

100% correct. Part #10778. Will sound better, flow better, perform under throttle better while retaining low end power.