Valve Rotation means Valve Float?
#2901570
03/22/21 12:11 PM
03/22/21 12:11 PM
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Joined: Oct 2006
Posts: 1,264
New York, USA
Chargerfan68
OP
pro stock
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OP
pro stock
Joined: Oct 2006
Posts: 1,264
New York, USA
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I was looking for information on factory and aftermarket valve keepers/locks and came across this written by someone in response to another question relating to rocker tip to valve contact pattern. Is the below true? Specifically that if the valve rotates with good aftermarket locks, then the engine experienced valve float? I never thought so, but now question the truth to this.
By non-rotating setup, he means the aftermarket locks that have gaps between the locks when installed. He states the factory 4 grrove locks butt up against eachother when installed and allow slight rotation of the valve when installed. That doesn’t sound right to me , about the 4 groove locks.
This is what he wrote:
“A non rotating setup should never show signs of wear on the valve tip other than a single bar where the rocker arm rides. If you see multiple patterns on this setup the engine has been in a valve bounce/float situation where the spring is no longer controlling the valve. Visualize the spring more or less staying compressed while the valve continues to close, now it's just good will holding the retainer/locks/valve stem package together, and in this situation the valve will rotate.”
1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.
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Re: Valve Rotation means Valve Float?
[Re: Chargerfan68]
#2901577
03/22/21 12:27 PM
03/22/21 12:27 PM
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Joined: Aug 2003
Posts: 43,157
Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,157
Bend,OR USA
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There are all kinds of theory on many different race parts, who wrote this information? All the stock valve rotaters (SP?) I've seen had a lot different set up on the locks that is mentioned in that statement 
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
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Re: Valve Rotation means Valve Float?
[Re: Cab_Burge]
#2901646
03/22/21 02:44 PM
03/22/21 02:44 PM
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Joined: Oct 2006
Posts: 1,264
New York, USA
Chargerfan68
OP
pro stock
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OP
pro stock
Joined: Oct 2006
Posts: 1,264
New York, USA
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It was just a guy responding to a question about valve tip rocker pattern on another forum. I know there is alot of mis-information on the web, but it did get me thinking. I have noticed on inspections of my engines roller rocker tip patterns indicating the valve is rotating. I have never noticed valve float as far as power drop-off or damage from valve float at tear down. But it got me thinking.
Another idea that i have that kinda disputes his statement is that as a valve spring or any coil spring is compressed, in my mind, i see the spring (viewed from the top or bottom) twisting in a circular motion. If the height gets shorter, and the o.d. Stays the same, it would have to travel in a circular, twisting motion. So it would naturally rotate the valve, back and forth at least. That’s the way i view it. Anything wrong with this thinking?
1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.
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Re: Valve Rotation means Valve Float?
[Re: Chargerfan68]
#2901865
03/23/21 03:47 AM
03/23/21 03:47 AM
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Joined: Sep 2014
Posts: 4,457
Washington
madscientist
master
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master
Joined: Sep 2014
Posts: 4,457
Washington
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I was looking for information on factory and aftermarket valve keepers/locks and came across this written by someone in response to another question relating to rocker tip to valve contact pattern. Is the below true? Specifically that if the valve rotates with good aftermarket locks, then the engine experienced valve float? I never thought so, but now question the truth to this.
By non-rotating setup, he means the aftermarket locks that have gaps between the locks when installed. He states the factory 4 grrove locks butt up against eachother when installed and allow slight rotation of the valve when installed. That doesn’t sound right to me , about the 4 groove locks.
This is what he wrote:
“A non rotating setup should never show signs of wear on the valve tip other than a single bar where the rocker arm rides. If you see multiple patterns on this setup the engine has been in a valve bounce/float situation where the spring is no longer controlling the valve. Visualize the spring more or less staying compressed while the valve continues to close, now it's just good will holding the retainer/locks/valve stem package together, and in this situation the valve will rotate.”
That is correct. If you see multiple patterns on the valve tip the valve train is very pissed off.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: Valve Rotation means Valve Float?
[Re: madscientist]
#2901940
03/23/21 10:27 AM
03/23/21 10:27 AM
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Joined: Jan 2003
Posts: 14,494
So. Burlington, Vt.
fast68plymouth
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 14,494
So. Burlington, Vt.
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The number of heads I get in the shop that are being used in competition engines turning high rpm........ that have a single line of contact on the valve tip is less than 1%....... as in almost never.
Not “never”, but almost never.
It is the very rare exception.......not the rule.
That’s with 30+ years worth of examples to look at, with heads that have come from countess different sources from all over the country.
To paraphrase Chris Uratchko......... “having the valvetrain perfectly smooth and stable isn’t always the fastest way down the track”.
68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads
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