{"id":11287,"date":"2019-04-23T05:45:35","date_gmt":"2019-04-23T13:45:35","guid":{"rendered":"https:\/\/corksport.com\/blog\/?p=11287"},"modified":"2019-04-22T15:05:07","modified_gmt":"2019-04-22T23:05:07","slug":"the-design-2-5l-skyactiv-g-exhaust-header","status":"publish","type":"post","link":"https:\/\/corksport.com\/blog\/the-design-2-5l-skyactiv-g-exhaust-header\/","title":{"rendered":"The Design &#8211; 2.5L SkyActiv-G Exhaust Header"},"content":{"rendered":"\n<p>A few months ago <a href=\"https:\/\/corksport.com\/blog\/oem-part-breakdown-2-5l-skyactiv-g-exhaust-header\/\">we broke down<\/a> the complicated design of the exhaust manifold found on the 2014-2018 Mazda 3 &amp; 6 2.5L SkyActiv. &nbsp;Mazda put extensive R&amp;D into the design and packaging of the OEM header to optimize the exhaust gas pulses and overlap. &nbsp;<\/p>\n\n\n\n<p>In this blog we are going to explain some of the design features in the CorkSport 4-2-1 header and why those features are important. &nbsp;<\/p>\n\n\n\n<p>Below is a diagram showing the primary, secondary and collector routing of the OE header. &nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"682\" src=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/4-2-1-Header-Mazda3-1024x682.jpg\" alt=\"Mazda 2.5L SkyActive Header\" class=\"wp-image-11288\" srcset=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/4-2-1-Header-Mazda3-1024x682.jpg 1024w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/4-2-1-Header-Mazda3-300x200.jpg 300w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/4-2-1-Header-Mazda3-768x512.jpg 768w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/4-2-1-Header-Mazda3.jpg 1229w\" sizes=\"(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><figcaption>The OEM header for the 2.5L SkyActiv engine has a 4-2-1 design.<\/figcaption><\/figure>\n\n\n\n<p>When designing a performance header we have to ask ourselves, \u201cwhat is the goal with this performance part?\u201d and then fulfill that goal. &nbsp;With the performance header for the 2.5L SkyActiv our goal was to increase mid-range torque, retain good fitment and user installation, and improve the sound output of the exhaust system. &nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"787\" src=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-6-exhaust-header-diagram-1024x787.jpg\" alt=\"CorkSport Aftermarket Exhaust Header\" class=\"wp-image-11289\" srcset=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-6-exhaust-header-diagram-1024x787.jpg 1024w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-6-exhaust-header-diagram-300x231.jpg 300w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-6-exhaust-header-diagram-768x590.jpg 768w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-6-exhaust-header-diagram.jpg 1200w\" sizes=\"(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><figcaption>CorkSport 2.5L SkyActiv header design.<\/figcaption><\/figure>\n\n\n\n<p>Immediately you\u2019ll notice a significant difference in the design of the OEM header and the CorkSport Header. &nbsp;There are three major differences:<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Primary, secondary, and collector diameters have been increased to promote better exhaust gas flow.<\/li><li>Primary and secondary runner lengths have been increased to optimize power\/torque lower in the RPM range.<\/li><li>The design is two-piece to drastically improve the installation process. &nbsp;<\/li><\/ol>\n\n\n\n<p>The primary runners (these are the runners that mate directly to the engine) have been increased in diameter from 1.55\u201d to 1.75\u201d and the secondary runners (these are the runners that combine only two cylinders before the collector) have been increased in diameter from 1.87\u201d to 2.00\u201d. &nbsp;Both of these changes improve peak flow per cylinder throughout the RPM range.  Lastly, the collector has been increased from 2.00\u201d to 3.00\u201d to be paired with the CorkSport 60.5mm or <a href=\"https:\/\/corksport.com\/2014-2018-mazda3-80mm-cat-back-exhaust.html\">80mm Cat-Back Exhaust Systems<\/a>. <\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"800\" height=\"532\" src=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/Mazda-3-race-engine-header.jpg\" alt=\"CorkSport Exhaust Header Installed\" class=\"wp-image-11290\" srcset=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/Mazda-3-race-engine-header.jpg 800w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/Mazda-3-race-engine-header-300x200.jpg 300w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/Mazda-3-race-engine-header-768x511.jpg 768w\" sizes=\"(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><figcaption>CorkSport Header Installed.<\/figcaption><\/figure>\n\n\n\n<p>Here\u2019s where things got a bit tricky. &nbsp;Increasing the length of the primary and secondary runners forced us to be a bit creative in routing all the piping. &nbsp;In order to achieve the primary runner length we wanted, we had to route the piping upward first (as you can see below) then back down between the engine and firewall. &nbsp;The results were better than we expected with a \u201cMedusa\u201d style header peeking out of the engine bay and the lengths we wanted.  <\/p>\n\n\n\n<p>It makes us grin every time we pop the hood open, we hope you love it as much as we do. &nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"681\" src=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-3-exhaust-manifold-diagram-1024x681.jpg\" alt=\"CorkSport 2.5L Exhaust Header broken down for install.\" class=\"wp-image-11291\" srcset=\"https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-3-exhaust-manifold-diagram-1024x681.jpg 1024w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-3-exhaust-manifold-diagram-300x200.jpg 300w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-3-exhaust-manifold-diagram-768x511.jpg 768w, https:\/\/corksport.com\/blog\/wp-content\/uploads\/2019\/04\/mazda-3-exhaust-manifold-diagram.jpg 1200w\" sizes=\"(max-width: 767px) 89vw, (max-width: 1000px) 54vw, (max-width: 1071px) 543px, 580px\" \/><figcaption>The final design of the CorkSport 2.5L header is installed in two pieces. <\/figcaption><\/figure>\n\n\n\n<p>However, the complicated CorkSport design did create a new problem. &nbsp;Installation!  We always try to create a performance part that can be installed by the average enthusiast in their garage and this was no exception. &nbsp;In a one-piece design, the header was nearly impossible to install.  We went to the drawing board and realized that separating the upper and lower halves of the header was the best option.  <\/p>\n\n\n\n<p>We considered a conventional flange, gasket and hardware setup, but realized it to was far too complex in the close quarters behind the engine. &nbsp;We then moved to a v-band connection that proved to be the best setup for installation, weight, and sealing ability.  <\/p>\n\n\n\n<p>That wraps up the design, next we\u2019ll breakdown the testing and results! Let us know if you have any questions or thoughts down below.<\/p>\n\n\n\n<p>-Barett @ CorkSport<br><\/p>\n","protected":false},"excerpt":{"rendered":"<p>In this blog we are going to explain some of the design features in the CorkSport 4-2-1 header and why those features are important to our new header.<\/p>\n","protected":false},"author":3,"featured_media":11289,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[553,9,40,131,77],"tags":[437,448,793,453,275],"class_list":["post-11287","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mazda-performance","category-mazda3","category-mazda6","category-research-and-development","category-skyactiv","tag-mazda3","tag-mazda6","tag-research-and-design","tag-skyactiv","tag-skyactiv-mazda"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/posts\/11287"}],"collection":[{"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/comments?post=11287"}],"version-history":[{"count":0,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/posts\/11287\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/media\/11289"}],"wp:attachment":[{"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/media?parent=11287"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/categories?post=11287"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/corksport.com\/blog\/wp-json\/wp\/v2\/tags?post=11287"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}