Difference between roller and flat tappet cams
Thread Starter
Team Owner
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From: Reno Nevada
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Difference between roller and flat tappet cams
https://www.onallcylinders.com/2019/10/14/mailbag-the-difference-between-flat-tappet-and-roller-camshafts/
https://www.hotrod.com/articles/flat-vs-roller-tappet-better/#:~:text=The flat-tappet cam lobe,opens the valve much faster.
http://www.superchevy.com/how-to/148-0307-basic-camshaft-info/
https://www.hotrod.com/articles/flat-vs-roller-tappet-better/#:~:text=The flat-tappet cam lobe,opens the valve much faster.
http://www.superchevy.com/how-to/148-0307-basic-camshaft-info/
Last edited by gkull; Oct 29, 2020 at 10:42 AM.
Le Mans Master
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From: Little Rock AR
Good articles but a few errors.
Another thing to keep in mind. Solid Lifters have a lash spec (clearance) so the .050" duration figures (which are GROSS tappet lift, not NET tappet lift) will mislead you when comparing the .050" duration numbers between a hydraulic lifter cam vs a solid lifter cam. The solid lifter cams will need to lift up the lash before the valve actually begins to open. Hydraulic lifter cams do not need to do that as they have zero lash. The solid lifter cam will perform like a "smaller duration" hydraulic cam if both cams have the same .050" specs.
Another thing to keep in mind. Solid Lifters have a lash spec (clearance) so the .050" duration figures (which are GROSS tappet lift, not NET tappet lift) will mislead you when comparing the .050" duration numbers between a hydraulic lifter cam vs a solid lifter cam. The solid lifter cams will need to lift up the lash before the valve actually begins to open. Hydraulic lifter cams do not need to do that as they have zero lash. The solid lifter cam will perform like a "smaller duration" hydraulic cam if both cams have the same .050" specs.
Last edited by stingr69; Oct 31, 2020 at 11:31 AM.
Is my vette stock?? HAHA
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Thats not true because at .050 lift you are on the ramp and getting .050 lift. Hydraulic lifters can and will bleed ouot and at high rpm they may not have time to pump up. Thats why high RPM users have solid lifter cams. Hydraulic lifters are for convenance, not performance for thee most part. If you are serious you are running a solid lifter
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,235
Likes: 9,376
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
And the ramps are steeper on a solid roller. Now if you want to just talk lifters on the same cam there are plenty of tests that do that, hotrod has published a few, and the solid roller makes more power.
Le Mans Master
Joined: Mar 2004
Posts: 7,503
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From: Little Rock AR
Thats not true because at .050 lift you are on the ramp and getting .050 lift. Hydraulic lifters can and will bleed ouot and at high rpm they may not have time to pump up. Thats why high RPM users have solid lifter cams. Hydraulic lifters are for convenance, not performance for thee most part. If you are serious you are running a solid lifter
Longer Explanation
Last edited by stingr69; Oct 30, 2020 at 03:16 PM.
