I have hooker longtubes with a mufflex y-pipe - will traingular subframe connectors work alright with this setup? Does anyone have any experience with this at all? If it wont work , what should I look into. Thanks!

 

A Ypipe should fit ok with DD SFCs, Straight pipes are a little harder to fit, I have purple hornies on my LTs but I had to shorten them a bit to clear the DDs.
Your tranny crossmember will probably give you more problems than the SFCs.

 

Kenny Brown DD's work fine with Hooker LT's/Mufflex Y-pipe. The Y-pipe interferes with everything else under the car, though.

Mike