how restrictive is the stock exhaust system?

Discussion in 'SN95 4.6L Mustang Tech' started by MotleyCrue, Dec 7, 2003.

  1. just as the subject says, is it super restrictive?

  2. I would say so. I gained 23 hp and 19 tq after going to lontube headers, offroad x and Magnaflow catback.

  3. IMHO, yes. I also wenr with long tube headers and off-road x-pipe and the added power is noticeable...and now my stang sounds great!

  4. :stupid:
  5. Not really if you compare it to the stock exhaust systems of the 70's. Back then you could gain 5% by installing dual exhaust, and another 10% by installing headers and the whole system cost $200. Now you'll spend over $1000 and gain 2-5%... :nice:
  6. With the vortech, my steeda dynoed 350rwhp with stock exhaust. I did all the labor and replaced the entire exhaust and headers. I picked up 20hp and a little more respect from anyone racing me. In exchange, it's hard to use my cell phone in the car and the radio has to be twice as loud. I would gladly give up the 20hp to get my quiet car back.
  7. Even as recently as the late 80's early 90's exhaust systems have been very restrictive. On a GM 305TBI, putting a full exhaust on could net you 50hp. The newer GT exhaust seems pretty good aside from the exhaust manifolds.
  8. I gained 20rwhp and 8rwtq over stock manifolds and a Bassani X pipe with my long tubes. I'd say it is pretty restrictive!
  9. Just strap on a drgas xpipe with flows. YOU will see the difference over stock :D

  10. Man, I'd never expect a reply like this one. Even a rag dynod an 03 Cobra with headers/midpipe/catback and got 55 hp!

    I would figure you would gain at least 25-30..

    Sorry to hear your dissapointment.

    I'm totally happy with mine.

  11. Here's a pic with the stock catback pipe on the left (just behind the midpipe connection) and the FRPP catback on the right. Notice a) the way my fingers can get around the stocker, but not the FRPP and b) the fact that there are several random bends in the stocker where the FRPP is pretty damn straight. Most other aftermarket catacks would be similar. Obviously not a conclusive study on the subject, but just one observation I had.


    Attached Files:

  12. Which is why I love having a stock exhaust system.
    Don't know about where you guys live, but around here police are big on what we call the "random pull-over."
    I work the grave yard shift and sometimes I'm the only car on the road, along with 4 or 5 cops, they don't notice you as much with stock exhaust.

    I plan to get the new BBK shorties and retain the stock midpipe and catback.
  13. I put a h-pipe on but kept the stock cat-back. It's louder but not 'get noticed' loud.
  14. if you want your car quiet, get an o/r h pipe and mac flowpaths. :D
  15. I would love to replace my midpipe, but sadly, in CA it is technically illegal.
  16. What in Cali isn't illegal as far as engines? :rolleyes:
  17. Superchargers (as long as it's got a CARB number), catbacks are fine (within noise regulations), cams or internal work as long as it still passes the sniffer.

    CA smog laws are simply retarded. It's illegal for me to swap out my mid-pipe with an aftermarket cat'd one, but it's legal for me to use aftermarket headers like the JBAs.
  18. I think if you can pass the sniffer, who cares what's under the hood. Wasn't that the point of CARB, to reduce emissions?
  19. I have just installed my LT/X-pipe with cats/new cat-back myself. I have yet to dyno the car because I have a leak :(
  20. :nonono: You're using rationality to reason out an idea. Rationality and reasoning is not something our state legislators are familiar with. Common sense would tell you "all the matters is what's coming out the tail pipes." The harsh reality is the visual inspection will burn you every time.

    CARB (California Air Resources Board) is beaurocratic nonsense, my 5.0 failed inspection because the timing was too far advanced. This was part of the visual inspection. Some parts make sense, like checking for breathers and how well the fuel cap works, but the timing and "factory" catalytic converters is just BS. What difference does it make in terms of anything really, how much timing you want to run in your car, running on pump gas? Makes no sense to me.