Manually Degreed Cam Lobes
03-09-2017, 02:49 PM
#21
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FWIW, I plugged that cam into my dynosim program. Changed the rocker ratio to 1 so it showed the actual cam profile and the curve it shows reflects almost exactly what I measured.
Bob
Bob
03-09-2017, 04:31 PM
#22
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OK Bill, just measured that cam every 2 degrees as you requested. Here's the short version: Beginning lift to 20 degrees the lift rose on average .002 every 2 degrees of crankshaft rotation, then .005 per 2 deg. up to 39 deg, .008 up to 51 deg, .009 up to 75 deg, .008 up to 81 deg, .007 up to 91 deg, .006 up to 101 deg, .005 up to 117, .003 up to 135 deg, .002 up to 145 deg, .001 up to 151 deg., 0 up to 162 then started closing at roughly the same rate. Hope this makes sense and can help you out. This is the exhaust lobe on the Howard cam which is 242.6 @ .050 and .640 lift, with a .377 lobe. Let me know if you need anything else. I still have the degree wheel attached.
Bob
Bob
Bill
03-09-2017, 04:51 PM
#23
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You really just need to interpolate the ranges I listed. I got some variations between readings which I'm sure is because I'm just reading a degree wheel and getting exactly 2 degrees each movement is impossible So using the average in each range is going to be as close as you can get without using a cam doctor or such. You can definitely see the change of intensity at the steps I listed. I'll see if I can get these numbers into an excel spread sheet and you can play with them. You certainly couldn't understand the scribblings I made while doing it.
Bob
Bob
03-09-2017, 05:15 PM
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I emailed you a spreadsheet with the actual numbers. If anyone wants them let me know and I'll email the spreadsheet. I can't post it on here because I'm too cheap...
