Roller lifters, Anyone tried them? |
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Roller lifters, Anyone tried them? |
r_towle |
Oct 26 2015, 09:31 PM
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#81
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Has anyone tried roller lifters in a type 4, or any flat motor?
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Bills914-4 |
Oct 31 2015, 12:34 PM
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#82
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Member Group: Members Posts: 311 Joined: 1-March 08 From: suburbs of Miami FL. Member No.: 8,762 Region Association: South East States |
Maybe I'm not seeing something but those roller lifters don't have the oil groove around
the body (to allow the oil up thru the push rods to rockers) and they don't look like they have any wear marks on the body dia. , maybe I'm wrong & this is not finished being set up (IMG:style_emoticons/default/confused24.gif) , plus they will need some form of locking the rotation . |
r_towle |
Oct 31 2015, 02:09 PM
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#83
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Custom Member Group: Members Posts: 24,624 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Maybe I'm not seeing something but those roller lifters don't have the oil groove around the body (to allow the oil up thru the push rods to rockers) and they don't look like they have any wear marks on the body dia. , maybe I'm wrong & this is not finished being set up (IMG:style_emoticons/default/confused24.gif) , plus they will need some form of locking the rotation . That is the part I don't believe is required, locking the rotation. What force would make them twist if they are in constant contact with the camshaft. If they are touching all the time they would be forced to stay square. For oil, it's possible there is a hole in the middle, not sure, no other pics. |
Dave_Darling |
Oct 31 2015, 07:02 PM
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#84
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914 Idiot Group: Members Posts: 15,048 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
What force would make them twist if they are in constant contact with the camshaft. If they are touching all the time they would be forced to stay square. Well, if there is valve lash, that can propagate all the way to the lifter, so there won't necessarily always be contact. And if there is any tendency at all for the lifter to turn at all, there doesn't seem to be a way that it will correct itself, so it will just get worse and worse until it gets to 90 degrees and turns into a lathe bit. Remember that the stock lifters are designed specifically to rotate, in order to spread the wear out. I think there is a slight built-in taper to the cam lobes that helps with this, and the lifter bores are offset from the cam axis as well. If you get the alignment perfect, and spec a cam with zero taper, you might be able to convince the lifter not to rotate. But unless you have a way to correct any rotation that may occur, eventually you're going to get one flipped 90 degrees and you'll be super unhappy. --DD |
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