How can you tell if you have flat cam lobes?, Strange lash issue |
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How can you tell if you have flat cam lobes?, Strange lash issue |
tornik550 |
Jun 15 2012, 02:27 PM
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#1
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Senior Member Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None |
I am paranoid of developing flat can lobes on my recent engine rebuild. I am paranoid cause I have heard so much crap about the cam that I used- scat c45. I am asking this more for curiosity sake. I had a strange issue but I am certain it's unrelated. I set my valves on cyl 1 to 0 lash (chromoly pushrods). I did that at tdc for that cyl. Te intake and exhaust valves. Seem to lift normally. The issue is that at a different point in the cycle (other than tdc or full lift) the valves are very loose. The valves go back to zero lash at TDC. The compression is actually about 5 points better on that cylander. I think it's possible that the rocker shaft bolts may have loosened a bit, however I've already removed them. It doesn't sound like a flat lobe to me.
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Dr Evil |
Jun 15 2012, 02:58 PM
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#2
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Send me your transmission! Group: Members Posts: 23,002 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region |
You are obviously not on the right part of the cam (IMG:style_emoticons/default/wink.gif) The cam will flatten on the nose thereby reducing your lift.
There are two spots on the cam that are like TDC, one is actually TDC. Ex open/close --> Intake open/close --> piston at top = TDC Intake open/close --> Ex open/Close --> Piston near TDC = NOT TDC (even though both valves are closed/ing) You want piston at TDC on the compression/ignition stroke between intake closing and exhaust opening. |
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