{"id":1745,"date":"2014-08-15T07:52:01","date_gmt":"2014-08-15T13:52:01","guid":{"rendered":"http:\/\/www.velocity-xl.com\/blog\/?p=1745"},"modified":"2015-01-27T18:03:32","modified_gmt":"2015-01-28T00:03:32","slug":"12-99-induction-air","status":"publish","type":"post","link":"https:\/\/www.velocity-xl.com\/blog\/2014\/08\/15\/12-99-induction-air\/","title":{"rendered":"12.99 Induction Air"},"content":{"rendered":"
This entry is part 41 of 50 in the series 12 - Engine \/ Propeller<\/a><\/div><\/div><\/div>

In a standard Continental IO550N installation, the way the engine gets air is through a “U” shaped duct that takes the rearward facing fuel injection servo and points the intake forward (remember the engine is in backwards).\u00a0 Since I’m going a different type of plenum, that part won’t work for me.<\/p>\n

An added issue is that the air is pulled directly from the upper area (which is supposed to cool the engine as it is pulled down) and there’s NO AIR FILTER!<\/p>\n

So I had this idea that I would make a NACA duct on the bottom, put an air filter down there and somehow create some ducting to get that clean air up to the top of the engine.<\/p>\n

I started with the part that I thought would be hardest. Making the ducts to get the engine intake extended to the lower cowling.<\/p>\n

So I used a trick that I learned from Malcolm for fast prototyping. Using some leftover blue foam, I made a slightly smaller version of the duct. Malcolm’s next door neighbor builds funny cars and has a lot of experience moving air to 1,000+\u00a0\u00a0\u00a0 \u00a0 horsepower engines. He said that squaring off the outside radius of the turns improves the airflow. So I squared off the outside part of the turns.<\/p>\n

\"_20140709_162434<\/a><\/p>\n

The next step is to cover the foam with duct tape. But with the curves on this part, that didn’t work too well. So I used electrical tape instead. Because it’s softer, it was able to make the turns better. Then I smeared vasilene over the part and covered it with 4 layers of BID.<\/p>\n

Once the epoxy cured, I poured acetone through the part which dissolves the foam. Then you just remove the tape and you’ve got your part.<\/p>\n

\"IMG_20140724_064107520<\/a><\/p>\n

The next part is the elbow to turn towards the lower cowling.\u00a0 By comparison, this is an easy part to make. Once again, I squared off the outside radius.<\/p>\n

Then I cut a hole in the aft baffle and joined the two parts with a friction slip-joint. I added a tab to assure it would stay in place.<\/p>\n

\"IMG_20140726_073803973<\/a>\"IMG_20140726_073756481<\/a><\/p>\n

All in all, I was feeling pretty good.<\/p>\n

I picked up a 11″x6″ K&N generic air filter from the auto parts store, measured it and (this time) used plywood to make the mold for the filter box.<\/p>\n

This would connect to the NACA on the lower cowl. Then I would make some ducting to get the air up to the elbow.<\/p>\n

And that’s when I figured it out… There’s just no room! The amount of space between the engine (and engine mount) isn’t big enough to allow for a submerged NACA.\u00a0 Let alone the almost 4 feet of ducting to get it up to the engine. I spent a lot of time researching various solutions but I just couldn’t figure out a way to make it work and not lose any performance.<\/p>\n

So I had to drop back and punt. I made a U and I’ll pull air from the upper plenum without a filter. \ud83d\ude41<\/p>\n

\"IMG_20140809_181956766<\/a>\"IMG_20140810_172101357<\/a><\/p>\n

I went ahead and painted it so at least it looks pretty.<\/p>\n

\"_20140818_162112<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

This entry is part 41 of 50 in the series 12 - Engine \/ Propeller<\/a><\/div><\/div><\/div>

In a standard Continental IO550N installation, the way the engine gets air is through a “U” shaped duct that takes the rearward facing fuel injection servo and points the intake forward (remember the engine is in backwards).\u00a0 Since I’m going … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[46],"tags":[],"series":[36],"class_list":["post-1745","post","type-post","status-publish","format-standard","hentry","category-46","series-12-engine-propeller"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/posts\/1745","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/comments?post=1745"}],"version-history":[{"count":5,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/posts\/1745\/revisions"}],"predecessor-version":[{"id":1962,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/posts\/1745\/revisions\/1962"}],"wp:attachment":[{"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/media?parent=1745"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/categories?post=1745"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/tags?post=1745"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/www.velocity-xl.com\/blog\/wp-json\/wp\/v2\/series?post=1745"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}