valve train pushrod geometry setting, weird question... maybe not |
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valve train pushrod geometry setting, weird question... maybe not |
orange914 |
Mar 18 2008, 05:23 PM
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#21
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http://5starmediaworks.com/index.html Group: Members Posts: 3,371 Joined: 26-March 05 From: Ceres, California Member No.: 3,818 Region Association: Northern California |
following the step by step valve geometry i've got a few possible issues? when no shims used and exhaust and intake geometry is set the swivel feet are almost bottomed out (almost no adjustment left). so next it was shimmed with .025, the geo/swivel tightness got better (not so close to bottoming against swivel) when shimmed with .040 shims i have more space to adjust up left before swivel contacts rocker (3/4 to 1 turn).
bottom line it seems to work out better with .040 shims. with no shims it has wider range of measurements between each valve -and- closer swivel foot to rocker arms. 1] is .040 shim o.k.? 2] if o.k. is 3/4 to 1 turn until swivel foot hits the bottom of the (modified) rocker acceptable? yes they are o.e.m. swivels from a 2.7 3] if not o.k. can i remove .030 or ? more from rocker arm 4] if none of the above is good what am i needing to do to correct this? mike |
toon1 |
Mar 20 2008, 02:33 PM
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#22
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
QUOTE The question is, WITH a .040 shim, the swivel foot is ONLY 3/4 of a turn from bottoming out aginst the rocker. That means you have 3/4 of 1mm of valve adjustment allowable.. If your valves stretch that far they'll snapp off. jake, with no shims we measered .440 INT. lift, and .419 EX. lift. Perfect valve train geometry at half lift had a bigger difference in lengths between intake and exhaust pushrods without a shim, but they were closer with .040 shims. (1)- i am not clear if .040 is advised or not needed? (2)-with no shims, having approx. half turn at most, will i have problems with swivil foot/rocker-arm interference? (3)-is it better to have a more equall exhaust and intake total lift that adding a .040 shim? so... the feedback i'm getting is: although the swivels are close to the rockers with no shims (3/8 to 1/2 turn from interferance), it isn't an issue. this is better than .040 shims no?? mike I think it's the other way around. With the swivel feet being so close to the rocker, if the valve stretches, you will run out of adjustment, not good. If I understand it right, what Jake is saying, 3/4 of a mm is NOT good We definitly need the shim. shims are not a bad thing (escpecially if they are nesacarry), we just need to know weather or not to add more. |
SirAndy |
Mar 20 2008, 02:42 PM
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#23
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Resident German Group: Admin Posts: 41,815 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
If I understand it right, what Jake is saying, 3/4 of a mm is NOT good if i understand jake correctly, he was saying 3/4 of 1 mm is PLENTY because if the valve ever stretches that much, it'll snapp off long before you bottom out your adjustment ... (IMG:style_emoticons/default/idea.gif) Andy |
orange914 |
Mar 20 2008, 06:16 PM
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#24
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http://5starmediaworks.com/index.html Group: Members Posts: 3,371 Joined: 26-March 05 From: Ceres, California Member No.: 3,818 Region Association: Northern California |
if i understand jake correctly, he was saying 3/4 of 1 mm is PLENTY because if the valve ever stretches that much, it'll snapp off long before you bottom out your adjustment ... (IMG:style_emoticons/default/idea.gif) Andy by the way andy i think i should confirm that these rockers i got from you were .060 cut? or were they done before you?... they look consistant and professionally cut so i'm not doughting just confirming. mike |
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