![\"\"](\"http:\/\/commons.princeton.edu\/63-tiger-cub\/wp-content\/uploads\/sites\/74\/2018\/08\/Engine-Diagram-2.bmp_.jpg\")
<\/p>\n<\/p>\n
We have the\u00a0R-type cam<\/strong>, which is the higher performance cam.<\/p>\n In our engine, we have\u00a0two cam lobes<\/strong>\u00a0and\u00a0two push-rods controlling two valves<\/strong>.<\/p>\n There are two oppositely-coiled helical springs which bring the rocker arm and\u00a0 valves back to their original position after each half-cycle, and help in keeping them in position.<\/p>\n The valve seats had to be recut, and we decided to do a\u00a0three angle valve seat<\/strong>.<\/p>\n The purpose of the seat is to form\u00a0a surface for the valve to seal against<\/strong>\u00a0during the compression and combustion stroke, so that the cylinder does not lose compression. \u00a0 If it does not seal, expanding gases will escape around the valves, lowering our efficiency and probably causing damage in the head.<\/p>\n A three angle valve seat is a popular method for higher performance engines. The idea here is to create a small, uniform ring at the correct angle to form a seal against the valve.<\/p>\n The process involved the following three cuts-<\/p>\n Once the correct seat was established, we lapped the surfaces to match exactly with the valves using a grinding compound, which was placed on the mating surface of the valve.<\/p>\n The valve was inserted into the correct position and spun, first by hand with coarser grit and then with a drill with fine grit.<\/p>\n<\/div>\n<\/div>\n This tool is used to cut the valves seats at a specific angle determined by the position of the three cutters. Each tool has one predetermined angle, therefore we used three different tools to cut our high performance three angle valve seats.<\/p>\n The Valve Guides serve a dual purpose –<\/strong><\/p>\n We decided to make new guides with Glenn\u2019s suggestion.<\/p>\n We used some\u00a0bronze bar stock<\/strong>\u00a0that was in the shop, and drew up the dimensions of the old guides on Pro-Engineering, but\u00a0enlarging<\/strong>\u00a0them so we could drill a new hole for them to seat in, rather than hoping they would fit nicely into the old spot, which was probably worn.<\/p>\n They are also\u00a0longer<\/strong>\u00a0than the old ones, and have closer tolerances, which means the valves will move more precisely.<\/p>\n We made the guides on the lathe, first making one end square.<\/p>\n<\/div>\n<\/div>\n The next step was to drill the\u00a0inside channel<\/strong>\u00a0for the valves, then bring the outside down to the correct diameter. \u00a0 The angle cut was next and we added chamfers on both ends.<\/p>\n The final step was cutting the groove for a ring that keeps the guides at the correct depth in the head.<\/p>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":" Cam and Valve Diagram The cam assembly consists of – the cam cam followers push-rods rocker arms We have the\u00a0R-type cam, which is the higher performance cam. The job of the cam is to control the timing for the intake and exhaust valves to open and close.\u00a0 Our high performance cam keeps the valves open … Continue reading “Head”<\/span><\/a><\/p>\n","protected":false},"author":6,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-299","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/pages\/299","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/comments?post=299"}],"version-history":[{"count":3,"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/pages\/299\/revisions"}],"predecessor-version":[{"id":322,"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/pages\/299\/revisions\/322"}],"wp:attachment":[{"href":"https:\/\/commons.princeton.edu\/63-tiger-cub\/wp-json\/wp\/v2\/media?parent=299"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"\"](\"http:\/\/commons.princeton.edu\/63-tiger-cub\/wp-content\/uploads\/sites\/74\/2018\/08\/cam-diagram.png\")
The cam assembly consists of –<\/strong><\/p>\n\n
The job of the cam is to control the timing for the intake and exhaust valves to open and close.\u00a0 Our high performance cam keeps the valves open for longer and allows for more overlap between the exhaust and intake as compared to the stock cam, resulting in a higher power output.\u00a0 The overlap and time of the opening and closing of the valves depends on the size and shape of the cam lobes.<\/div>\n\nR-type Cam and Followers<\/h3>\n
\n![\"\"](\"http:\/\/commons.princeton.edu\/63-tiger-cub\/wp-content\/uploads\/sites\/74\/2018\/08\/cam-and-followers.jpg\")
<\/div>\n<\/div>\n<\/div>\n<\/div>\n\nOur Engine<\/h4>\n
\n\n\t\t\t\t
<\/a>\n\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\n\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\nValve Seats<\/h3>\n
\n\n\n
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Detail of Mating Surface on Valve<\/h3>\n
\nCutting Tools<\/h3>\n
\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\n\t\t\t\t<\/a>\n\t\t\t<\/div>\n\t\t\t\t\n
Pro-Engineering Technical Drawing of Valve Guide<\/h3>\n
\n<\/div>\n<\/div>\n\n<\/div>\n\n