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#1
06-06-2020, 02:41 PM
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Everything You Need to Know about Valvespring Technology
Part 1, Everything You Need to Know about Valvespring Technology
https://www.hotrod.com/articles/ever...ng-technology/ In Part 2, HOT ROD Looks At How The Vast Improvements In Spring Design Affect Spring Selection, Usage, And Installation In Different Performance And Racing Venues. https://www.hotrod.com/articles/revo...nology-part-2/ .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
| The Following 2 Users Say Thank You to Steve C. For This Useful Post: | ||
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#2
06-10-2020, 08:09 AM
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Very interesting article. Thanks Steve.
I did not know Suzuki is one of the major developers for valve spring wire. A lot of development background in that article. The section on harmonics and coil binds was very informative. Especially when they went into the conical springs. It never occurred to me the quick car of drag week were abusing the springs twice as much as the NASCAR cup engines. Reading the lifter paragraph you would think all our lifter failure were things of the past. The “every 4 to 5 years the lifter technology advancements double” does not seem to be making it back to most of our street machines...yet Last edited by Jay S; 06-10-2020 at 08:16 AM. Reason: Edit |
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#3
06-10-2020, 08:30 AM
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I'm trying to decide which rocker ratio to use for my new motor with E heads. Based on installed height and coil bind, I measured both, I have up to 0.638" lift with a distance of 0.060" from CB. If I use a 1.6 rocker I will have 0.640" lift but I have never run that close to CB before, has anyone run that close without issue? I know it is preferable to run closer rather than further from CB for spring control, but is 0.060", or 0.058" safe?
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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
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#4
06-10-2020, 08:31 AM
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Repeating the words of my mentor spoken to me WAY back in the 1970's.
"If you ever die and go to heaven don't get reincarnated as a valve spring".....LOL.....
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If you can read this, thank a teacher. If you can read this in English, thank a Veteran! https://cliffshighperformance.com/ 73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile), |
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#5
06-10-2020, 08:48 AM
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Your life might be ok if you came back in non Jr dragster go cart motor!
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Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs! And he was not talking about 1/8 or 1/4 mile ETs! 1) 1940s 100% silver 4 cup tea server set. Two dry rotted 14 x 10 Micky Thompson slicks. 1) un-mailed in gift coupon from a 1972 box of corn flakes. Two pairs of brown leather flip flops, never seen more then 2 mph. Education is what your left with once you forget things! |
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#6
06-10-2020, 09:54 AM
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"About 0.060 inch used to be the textbook safety margin, with more OK and even desirable. That's still an acceptable standard for everyday performance use, but for cutting-edge setups the "correct" safety margin can vary up or down."
"Depending on the intended use and the spring and cam-lobe design, coil-bind safety margins can now vary from 0.015 to 0.120 inch, with tighter numbers predominating on very stiff valvetrains. Anything more than 0.150 inch may cause spring surge, which can greatly reduce the available spring load needed to close the valve." Source: https://www.hotrod.com/articles/how-...rance-is-safe/ .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
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#7
06-10-2020, 11:41 AM
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My motor is not cutting edge race, just hot street so I guess it would be trial and error to determine if 0.060" is enough. I would hate if it was the error side and I was crunching coils and breaking or bending stuff.
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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
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#8
06-10-2020, 12:15 PM
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Distance to coil bind discussion..........
https://www.speed-talk.com/forum/viewtopic.php?t=5584 Others out there.... " I always tell people that .050 away from coil bind is as tight as I would ever run a spring. I have never seen ( at least with the engines I have worked with) a spring that benefited from running it tighter than .050. Some springs like to be farther away from coil bind than others. On a Pro Stock engine they are about .120 away from coil bind. It depends on, the spring design, the camshafts lobe design, valve train weight and the amount of loft your are trying to control." https://www.speed-talk.com/forum/viewtopic.php?t=432 .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE Last edited by Steve C.; 06-10-2020 at 12:22 PM. |
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#9
06-10-2020, 01:14 PM
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A lot of great info in your references, I have read a lot of it before. I run between 0.080"-0.095" on my race car that goes to 6700 rpm and it doesn't skip a beat. I just want to get the maximum lift I can on my street motor so I'm not sure if I should try the 0.055"-0.060" spec with a 1.6 rocker or go with a 1.5 rocker and have more distance to CB. The springs are the smaller diameter spring package that Dave B uses from Comp with a hardened steel retainer.
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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule. |
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#10
06-10-2020, 01:51 PM
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It can be a 'complicated' subject. Another related fly in the ointment......
"We’ve experienced valve float problems created merely by adding a 1.6:1 rocker arm over a 1.5:1 ratio. This occurs because the increased ratio accelerates the valve that much faster and causes the spring to lose control." https://www.enginelabs.com/engine-te...s-in-distress/ Cliff's comment in his post #4 brought a smile. But also very appropriate in that valve springs are among the most highly stressed components inside any engine. Doesn't really matter if cutting edge race, hot street or a "stock" type build. .
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'70 TA / 505 cid / same engine but revised ( previous best 10.63 at 127.05 ) Old information here: http://www.hotrod.com/articles/0712p...tiac-trans-am/ Sponsor of the world's fastest Pontiac powered Ford Fairmont (engine) 5.14 at 140 mph (1/8 mile) , true 10.5 tire, stock type suspension https://www.youtube.com/watch?v=qDoJnIP3HgE |
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