FLP Longtube Headers: 



    The whole system, with cats, offroad pipes & Y-pipe:


Cat & offroad pipe:


Driver's side header installed:  


Driver's side header & cat from below:  

Driver's side header with Offroad Pipe:

  Passenger's side:



  One of the reasons I chose the FLP's was for ground clearance. There just isn't much room under these cars and I thought the FLP's were a pretty good compromise--you do lose more ground clearance than with a set of shorties, but not all that much. And I didn't want any damn shorties!

Here is the most likely point of contact:

  That's the driver's side, well after the header. The header itself tucks up very well with no ground clearance loss. But GM never intended exhaust to run on this side of the car--and it shows. The clearance here could be helped by running a section of oval pipe (and getting rid of the cat, of course) for that section of the Y-Pipe. I'm only lowered a little less than 3/4" in front so it hasn't yet been a problem for me--but I haven't gone out of my way looking for speedbumps either.

Here's a shot from the front:

  As you can see, the passenger's side header hangs down pretty low. But that's the lowest point on that side and since it's farther forward I don't think it's as likely to drag on speedbumps, etc. From the header back, the exhaust is actually higher than stock since GM provided the room for it.

Here's a shot from the back that shows this pretty well:

Now for the cat-back:

Mufflex 3 1/2" catback with Spintech muffler:

The Mufflex Intermediate pipe is meant to slip fit onto the stock Y-Pipe.  The FLP Y-Pipe is meant to slip over a 3" catback.  Naturally, they don't match.  Since I don't yet have a welder, I bought an adapter--it didn't fit.  I ended up temporarily installed it with the Mufflex slipping over the FLP Y.  It's a loose fit even when shimmed:

Definately not recommended.  I finally found the correct part to connect the two:

That's the Flowmaster "Collector Reducer" or "Venturi Reducer Cone" depending upon which description you read.  Flowmaster Part Number R3530, sold in pairs, available from Summit, etc.  Perfect fit:

The Mufflex's usually come with a Flowmaster muffler but have lately added Spintech as an option. After having Flowmasters on my Belair and being sick and tired of the sound along with every other Mustang driving down the street having them, I wanted something different. While I figured I'd probably end up replacing it, I gave the Spintech a chance. It failed.

The quality was less than
impressive. The inlet and outlets were out of round, one was oversized and one was undersized. You can imagine what a PITA that made trying to install it with clamps.... And the sound didn't win me over. It sounded pretty mean at idle and light throttle (pretty loud as well) but sounded much like a flowmaster (oversized vacuum cleaner) at WOT except somehow this vacuum cleaner sounded like it was "spinning" while it made its noises. In addition, it was big, heavy and ugly. I'm a perfectionist. When I do something, I want it right. This wasn't. Enter "Plan B:"


A Borla XR-1 Racing Muffler. The quality difference isn't even funny, they aren't even in the same class. While the Spintech looks like it was made in sombody's garage, the Borla looks like it was made by pros. The inlet and outlet were actually round and the correct size. Daily driving the thing in Seattle, it's nice to know it's 304 Stainless. I've already rusted through one 409 stainless SLP muffler since I've been here.

Here's a shot of them from the ends:

The Borla is obviously a straight through design while the Spintech is not. Something else rather notable, (Mike will like this) the Borla weighs 1/2 what the Spintech does.

Here's the end result:


Given the straight-through design of the Borla, I had to move the exhaust hanger on the driver's side: 

  Oh, and I obviously cut off the turn-down at the end of the Mufflex and put on a decent looking tip. I had planned to do that all along.