Neither, it's a mod motor.
small blocks were 221, 260, 289, 302 (5.0) & 351W
big blocks were 352, 390, 406, 427, and 428
351C, 429, and 460 were 385 blocks.
There are some folks on here that have the Ravin mufflers. They are sold by Midas, but they are not made by Midas. I have heard them and they sound good, and the owner who had them seemed to like the power too!
I have one of the first Catted h-pipes from MRT. I like the sound and had no major problems, but mine just doesn't fit right. My left tailpipe is at a different angle than the right pipe, and actually points upward.
I vote for the FRPP. Go to www.mustangexhaust.com to hear my sound clip with MRT catted h-pipe. The fit was perfect and there is no drone, but it sounds good.