Page 5 of 7 FirstFirst ... 34567 LastLast
Results 41 to 50 of 63

Thread: Custom QUIET Performance Exhaust

  1. #41
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    The elbow sticks out less from the collector pipe than the O2 sensor does. If you install it so that it angles upward toward the engine, when you install the O2 sensor into it, the sensor is parallel to the collector. It's actually more compact than it would be without it.

    I'll try to get a picture tomorrow, maybe. Gotta get way under the car to get that photo. Unless I can do it from the engine bay.


    Simplify and add lightness.

  2. #42
    Banned
    Join Date
    Jun 2018
    Location
    Philippines
    Country
    Philippines
    Posts
    15
    Garage empty: add car
    Thanks
    0
    Thanked 0 Times in 0 Posts
    Quote Originally Posted by Loren View Post
    Unexpected knock on my door this afternoon. USPS gets an A+ for timely delivery. C- for having updated delivery information.

    No box, but very well cocooned in many layers of bubble wrap, paper and tape. :thumbwink:


    Looks good enough. If it fits as good as it looks, I'll be very pleased!


    6 bolts and two O2 sensors. I may go ahead and install it tomorrow. (I have an autocross Sunday)
    What brand is this headers?

    Thanks.

  3. #43
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    Quote Originally Posted by GearSpeedKelvo View Post
    What brand is this headers?
    It's a SpeedCircuit header, as stated in the first post.
    Simplify and add lightness.

  4. #44
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    Did some down and dirty accel runs and tried to crunch the data. First off, I wanted to change my testing method to doing 60 fps video rather than 30 fps. But, my phone only does 30, and I'm too lazy to get out the other camera. So, 30 fps. So, each frame = .033 seconds. We just have to live with that level of accuracy, I guess.

    I've decided that I want to burn some more fuel and give the ECU a chance to adapt to the latest change to the exhaust system. Then I'll retest a little more carefully than I did tonight.

    But, I can say for sure that the exhaust made a BIG change in the 4000-5500 area. It "feels" torquier lower than that, but it's not showing in the data. But, from 4000-5500 is dead flat in the acceleration curve where there was a big dip before.

    Unfortunately, I'm showing even LESS pull from 5500-6000. Which doesn't make sense. Maybe I do need to cut out that 1.5" restriction in the header? And then, I probably need to do some work on the intake to help get more and cooler air into the engine.

    Or, maybe I just need to take a little more time to be sure my testing is done properly. I was rushing tonight.

    Will revisit sometime next weekish. Meanwhile, I'm gonna drive it like I stole it and let the computer learn and me get used to how it feels.
    Simplify and add lightness.

  5. The Following 2 Users Say Thank You to Loren For This Useful Post:

    Daox (06-22-2018),inuvik (06-22-2018)

  6. #45
    Administrator Daox's Avatar
    Join Date
    Jan 2013
    Location
    Germantown, WI
    Country
    United States
    Posts
    4,999
    Thanks
    2,892
    Thanked 1,804 Times in 1,017 Posts
    Very interesting... Looking forward to seeing the data.
    Custom Mirage products: Cruise control kit, Glove box light, MAF sensor housing, Rear sway bar, Upper grill block

    Current project: DIY Nitrous oxide setup for ~$100

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage DE 1.2 manual: 47.2 mpg (US) ... 20.1 km/L ... 5.0 L/100 km ... 56.7 mpg (Imp)


  7. #46
    Moderator inuvik's Avatar
    Join Date
    May 2015
    Location
    Coos Bay, OR
    Country
    United States
    Posts
    3,835
    Thanks
    4,761
    Thanked 1,562 Times in 1,120 Posts
    Loren, have you had a chance to any more testing?

        __________________________________________

        click to view fuel log View my fuel log 2015 Mirage ES 1.2 automatic: 40.5 mpg (US) ... 17.2 km/L ... 5.8 L/100 km ... 48.6 mpg (Imp)


  8. #47
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    I got my hands on the sound meter. May have time to play with it tomorrow.
    Simplify and add lightness.

  9. #48
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    Quote Originally Posted by inuvik View Post
    Can you post a pic with the elbow installed to show how it fits in the space?
    I took this photo a while back, forgot to post it. It's looking down from the top behind the engine. The black cables that I wrapped the O2 sensor wire around are the shifter cables.

    Simplify and add lightness.

  10. The Following User Says Thank You to Loren For This Useful Post:

    18slcmirage (11-11-2020)

  11. #49
    Senior Member Qrush's Avatar
    Join Date
    Oct 2017
    Location
    Jacksonville, FL
    Country
    United States
    Posts
    214
    Thanks
    68
    Thanked 78 Times in 48 Posts
    Quote Originally Posted by Loren View Post
    I took this photo a while back, forgot to post it. It's looking down from the top behind the engine. The black cables that I wrapped the O2 sensor wire around are the shifter cables.

    Nice improvisation. Have you had any CEL's? Since my last "defouler" configuration, it only comes on (rarely) during a "hard pull" for sustained periods. like during highway driving over 4000 rpm for a bit. then after the car cools after shut down, the light will go off shortly after, during the next run. its never on for very long at all when it does rarely show.

  12. #50
    Still Plays With Cars Loren's Avatar
    Join Date
    May 2018
    Location
    Florida
    Country
    United States
    Posts
    1,225
    Thanks
    324
    Thanked 936 Times in 539 Posts
    I haven't seen a CEL at all since I put the extender on there.

    But, I have to share a stupid story. I need to start with the fact that I'm an old guy with no young children, no grandkids, and generally no need to care about festivities such as Independence Day fireworks. My wife was off today. I take Wednesday's off, anyway. Pretty ordinary "day off" for me except that I smoked some ribs.

    So, I'm sitting around the house, it's 8:30ish. I remembered that I needed to take some sound readings and try to redo my acceleration tests for the new exhaust. Well, hell, I'll just go do it now. There's less traffic in the evening, and the industrial park over in Mexico should be deserted.

    I get to the stop sign headed out of my neighborhood... gee, there's a lot of traffic. The light down the street must have just changed. But, dang... it just keeps coming. Weird. But, I finally get out. And I'm driving down the road toward downtown Safety Harbor when suddenly it dawned on me. It's the 4th of July! And it's almost dark. All of these idiots are going downtown to watch the fireworks over the bay!

    Total wasted trip.

    Well, I was able to get some in-car readings, and 10' readings in my driveway. But, there was way too much ambient noise to trust the 50' readings, and the bridge that I'd have to drive over to get the industrial park is prime fireworks watching area, so I didn't want to go anywhere near there.

    So, what did I learn? Well, I'm going to redo this and publish "formally" eventually. But, the car is 2db louder at idle with the fan off. 1db louder with the fan on 1, and exactly the same with the fan on 3. So... louder at idle, but still quiet enough to be masked by my typical fan setting.

    10 feet behind the car, it's the same at idle, 4db louder at 3500, and 1db louder at 6000. Interestingly, that sort of jives with the power improvement that I think I'm seeing. Making more power and more noise in the mid-range. Not making much more power or noise at the high end.

    There was too much traffic for me to get good a good cruising reading in 5th. At 5000 rpm in 1st, it was actually about the same, maybe even 1db quieter. At 4000 in 3rd, it's maybe 1-2db louder.

    Full throttle acceleration, the peak level is about the same. Still 83-84 db. It's surely louder than it was as you pass through the mid-range, and maybe it's at or near peak volume for a longer period of time, but the PEAK value is still the same.

    The numbers aren't nearly as loud as what it seems like TO ME in the car. I think it's more a change in the character of the sound. It's got a deeper tone, but the sound level just isn't a whole lot louder.

    Outside the car, it does have a slight rasp if you free-rev it. But, when you're driving, it can't accelerate fast enough to generate that same rasp. When I asked all of my friends at the autocross Saturday if my new exhaust was too ricey, they all said they didn't even notice that I'd changed anything. So, it's still very quiet.

    I guess there's one benefit to doing so many rainy autocrosses this year. I have three in-car autocross videos, all in similar weather with the windows up or nearly up, so less wind noise. You can definitely hear the difference.


    Stock Exhaust - May 5


    With Header - June 3


    With Header and full 1.75" exhaust - June 30



    Simplify and add lightness.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •