 Cam Shaft Geometry, Lift on cam not on valve |
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| tracks914 |
 Jan 7 2004, 08:54 PM
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#1
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Canadian Member  Group: Benefactors Posts: 2,083 Joined: 15-January 03 From: Timmins, Ontario, Canada Member No.: 153 Region Association: None   |
I have my engine apart (1.7) and have measured my cam but I can only find specs valve lift (actual movement of the valve) not cam lift (movement of the vavle divided by rocker ratio)
If I knew the rocker ratio I could figure it out too. I just want to know if my cam is still good. Tx Doug |
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Replies(1 - 2)
| Jake Raby |
Jan 7 2004, 09:00 PM
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#2
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Engine Surgeon Group: Members Posts: 9,394 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
divide the valve numbers by 1.3
Thats the gross cam lift |
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| tracks914 |
Jan 9 2004, 10:05 PM
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#3
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Canadian Member Group: Benefactors Posts: 2,083 Joined: 15-January 03 From: Timmins, Ontario, Canada Member No.: 153 Region Association: None |
If I multiply my cam lift by 1.3 I end up with .351" / .373" lift on the valve. Those measurments are almost exact on the other 2 lobes as well so any wear on the cam was even.
WebCam site shows Type 1 stock grind as .358" / .358" but doesn't list stock grind for Type 4's. It only jumps up to .430" for their hydraulic grinds and performance grinds from there up. Has anyone measured their new stock cam to see what the lobe sizes were then subtracted the highest from the lowest numbers? |
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