here's the Madfan e-fan info. highly recommended product.
http://http://www.madenterprise.com/fanstuff.htm
as for cats. 2 1/2" inlet/ outlet. approx 12- 14" length. don't have the part #, but they're universal so a little welding will be necessary.
you can go forward and port the heads, and go with a better cam, but the rods and pistons on these trucks are off the shelf ford parts, non-hi-po, so you have to be careful with a safe tune and amount of boost. IMO, save some $$ for a Whipple/ built motor eventually, but you should be able to enjoy the Eaton for now w/ a stock block.
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FUZION
1986-2007
07 DA HD #5694 FRPP 4.10's, T/A diff cover, S & B Intake, Diablo Predator, GF 2 / 5 DROP, Hellwig rear sway bar, Motoblue Underdrive crank pulley, Roll n Lock, AVS in-channel window visors, NHTOC rear window decal, smoked rear 3rd brake light and tails, 2008 HD wheels.
67 Camaro RS
