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  1. #121
    Veteran Member Three Rings
    Join Date
    Dec 16 2020
    AZ Member #
    578109
    Location
    NY, NJ

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    Someone tell me I'm wrong. But this looks a bit wonky. Lots of bends and pipe flow. Wouldn't you want less plumbing to reduce restriction?

    Sent from my SM-N981U using Audizine Forum mobile app

  2. #122
    Established Member Two Rings 9kracing's Avatar
    Join Date
    May 28 2024
    AZ Member #
    988133
    Location
    Bay Area

    Quote Originally Posted by Crowlski View Post
    Someone tell me I'm wrong. But this looks a bit wonky. Lots of bends and pipe flow. Wouldn't you want less plumbing to reduce restriction?
    Here's a post from 2004 by Bisimoto, on why his headers have the bends they do.



    "Greetings all,
    I was notified of this post, and quite suprised at some of the comments generated.

    The rationale for the bends on my designed header is a follows:

    I noticed a given area beneath our vehicles that can assist with the scavaging effects of the header. This was realized with manometer/ pressure differential tests done on my crx, and 2 other civics.

    I was pressed to design a unit that could terminate at this area for obvious reasons. I also had the additional challange of an ideal length of header piping to allow optimum exhaust pulse tuning, which was dependant on RPM range, displacement, etc.

    My experimentation with fluid dynamic concepts of "flow in pipes" proves that you can achieve the same flowrate and fluid friction in a given stright pipe in one of specified bends if sized properly. In simple terms, a smaller stright pipe flows the same (and experiences the same friction losses) as a calculated "bent" one of larger diameter. There is plenty of scientific documentation on this subject as well.

    Hence, this concept is one I use on my own race car to generate ideal HP and torque numbers, with a very simplistic setup: simple carbs, a SOHC, and ignition!

    As for the F1 analogy, yes, clearance/aero package may be the reason, but I had compartment constraints as well. In regard to underhood temperatures, I always suggest ceramic coatings...just like on my vehicle.

    I am not a businessman trying to sell headers. I am an engineer, scientist, and racer who desires to bring great technology to the masses...at a decent price."

  3. #123
    Veteran Member Three Rings
    Join Date
    Dec 16 2020
    AZ Member #
    578109
    Location
    NY, NJ

    Quote Originally Posted by 9kracing View Post
    Here's a post from 2004 by Bisimoto, on why his headers have the bends they do.



    "Greetings all,
    I was notified of this post, and quite suprised at some of the comments generated.

    The rationale for the bends on my designed header is a follows:

    I noticed a given area beneath our vehicles that can assist with the scavaging effects of the header. This was realized with manometer/ pressure differential tests done on my crx, and 2 other civics.

    I was pressed to design a unit that could terminate at this area for obvious reasons. I also had the additional challange of an ideal length of header piping to allow optimum exhaust pulse tuning, which was dependant on RPM range, displacement, etc.

    My experimentation with fluid dynamic concepts of "flow in pipes" proves that you can achieve the same flowrate and fluid friction in a given stright pipe in one of specified bends if sized properly. In simple terms, a smaller stright pipe flows the same (and experiences the same friction losses) as a calculated "bent" one of larger diameter. There is plenty of scientific documentation on this subject as well.

    Hence, this concept is one I use on my own race car to generate ideal HP and torque numbers, with a very simplistic setup: simple carbs, a SOHC, and ignition!

    As for the F1 analogy, yes, clearance/aero package may be the reason, but I had compartment constraints as well. In regard to underhood temperatures, I always suggest ceramic coatings...just like on my vehicle.

    I am not a businessman trying to sell headers. I am an engineer, scientist, and racer who desires to bring great technology to the masses...at a decent price."
    Totally get why headers are bent the way they are. Just the catback system seemed to have a few too many bends. But hey I'm not the designer so if they can show a positive scavenging of exhaust gasses and a positive vacuum then who am I to question. Thanks for that tho.

    Sent from my SM-N981U using Audizine Forum mobile app

  4. #124
    Senior Member Three Rings
    Join Date
    Sep 12 2022
    AZ Member #
    804400
    Location
    South Jersey

    Has anyone who ordered a 485 exhaust during their Black Friday sale actually gotten their exhaust yet?

  5. #125
    Junior Member Two Rings
    Join Date
    Sep 04 2023
    AZ Member #
    952595
    Location
    New York, NY

    Quote Originally Posted by Jetdriver View Post
    Has anyone who ordered a 485 exhaust during their Black Friday sale actually gotten their exhaust yet?
    Lol. Yeah their production times are a little insane. Took a while for me to get my exhaust. I did see the owner post a handful of RS3 rear sections last night so I'm sure you're coming up soon.

  6. #126
    Senior Member Three Rings
    Join Date
    Sep 12 2022
    AZ Member #
    804400
    Location
    South Jersey

    Quote Originally Posted by JustinP142 View Post
    Lol. Yeah their production times are a little insane. Took a while for me to get my exhaust. I did see the owner post a handful of RS3 rear sections last night so I'm sure you're coming up soon.
    Ok, cool. I'll have to check it out. On IG, I assume? I'm just a little perplexed because a week or so after I placed my order late Nov/early Dec, I emailed them to cancel the order. I found out one of my kids needed braces, so I was like maybe I shouldn't drop $3,500 on an exhaust right now... lol So I emailed Nick to cancel (they actually have a no-cancel policy, which I didn't realize when I emailed him) and he told me that they had already started production on my exhaust. I said, Ok, nvm, no problem. Here we are in early Feb... lol I'll keep waiting. Not in a big rush to put it on anyway. Maybe they send them all out in bulk for some sort of shipping discount. Who knows?

  7. #127
    Veteran Member Three Rings
    Join Date
    Sep 27 2020
    AZ Member #
    566751
    Location
    Livermore,CA

    I figured 8 weeks was the norm. I'm at week 5. But then there was Christmas and such. Prolly get it march 1st ish

    Sent from my SM-S901U using Tapatalk

  8. #128
    Established Member Two Rings 9kracing's Avatar
    Join Date
    May 28 2024
    AZ Member #
    988133
    Location
    Bay Area

    FWIW I was just talking to Nick about something else for a different a car, but he had this to say about our 8Y orders...

    "As far as the 8Y order goes, I'll get over some pics. We knocked out a bunch this week and I will have yours shipped very soon. "


    I think we'll see them sooner than later.

  9. #129
    Senior Member Three Rings
    Join Date
    Sep 12 2022
    AZ Member #
    804400
    Location
    South Jersey

    Got an email tonight from Nick confirming my address and said that they're just wrapping up the 8Y exhausts, so we must be getting close. He said he'd send some pics soon.

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