Ok, well, it looks like I'll soon have to start looking around for an exhaust system for my 88 T-bird 5.0 SO. It has console-shift (may become relevant to this discussion). Right now I've got the stock 2 cats into a third big cat into 2 mufflers and tailpipes.
Anyway, in my ideal world, sound-wise, I wish I could freeze the decay of my exhaust system in time right now. It sounds PERFECT! A very muffled sort of contented rumble. Imagine listening to a stock 5.0 Mustang, but lower pitched, and listening through a pillow stuck to each side of your head. It's like all the sound's higher frequency resonance has been filtered out. Sorta like a sleepy giant. I wish I could describe this accurately, but anyhoo.
Now, what I need to pass inspection (not for a few months) is everything after the cats, since everything up front is still intact. However, the downside to that is that 1) I want true-duals, and 2) from inside the car, the factory system is dead-quiet, I can't hear the exhaust AT ALL.
But, I was also considering going with a bone-stock Mustang-style setup, completely, front to back. However, given the relatively low-revving, bottom-end-grunt of the SO 5.0, will the improved flow actually hurt my bottom end torque any? I'd prefer not to lose any of my under-2000 RPM torque, since my car spends almost all of its time under 2K, and the majority of that at 1500 or less. Still, on rare occasion, I do like to mash the gas down a bit (less often these days with the price of gas, though!)
Now, *if* the bone-stock Mustang system is a good match for me, do they make somewhat quieter mufflers that flow well for it?
Also, with the stock Mustang system, does everything up to and including the mufflers fit as-is? I know that I have to use extenders or otherwise longer pipes after the mufflers, due to the T-bird's increased length, but I wasn't clear on what happens up to and including the mufflers.
And finally, again *if* the bone-stock Mustang is what I'm going to go with, from a tech article at coolcats.net
, there's the following:
Now with the floor shifter, there's another unique problem. The bracket that holds the kickdown cable (aka TV - throttle valve) on the transmission hangs down just enough to interfere with the H-pipe. You will need to grind down the bracket approximately 1/2" to get the H-pipe to fit right. Believe me, there is nothing more annoying than having the H-pipe squeak every time you hit a bump. For all transmissions alike, please be aware that the factory H-pipe with 4 catalytic converters comes really close to the kickdown linkage on the driver's side of the transmission. If you're not careful with clearances in this area, your kickdown cable can get stuck on the top of the converter and you'll experience some nasty shifting. This is not a safe situation. My advice to you: remove the heat shield surrounding that particular converter (the smaller one, toward the front) before you install it. That should assure you of no clearance problems in that area.
I took a look down there, and it looks like there's two places the author might be referring to, but a quick inspection seems to indicate that there isn't 1/2" worth of material to grind down!
Finally, I am wondering if the Walker replacement H-pipe might alleviate this as well, since they have only 2 cats instead of 4. Still, I don't know if Walker's diagrams are showing an elimination of the front or back converter....
From the Walker Catalog for a Mustang 5.0
1986-1988 Mustang 5.0 - All models before 5-88, except 87-88 GT
1987-1993 Mustang GT 5.0
1987-1993 Mustang LX 5.0 after 5-88
Looks like they've made a single catalyst for each side that's a combination of the two that were from the factory. Will this alleviate the kickdown bracket clearance issue?
Thanks in advance. I'm sure I've forgotten a couple of questions that I'll probably have.....