3 Q's - Valve Springs, Valve Rotation & Rocker Stud Hole ???

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Valve spring replacement schedule ???


I have roughly 15,000 miles over 5 years on the original Brodix valve springs. Is it all about the number of cycles or does time have to be factored into this equation? How often should they be changed when the lift is .560 inches. I sure don't want to drop a valve, it would NOT be worth a set of new valve springs.

Should I see more valve rotation ???


Looking at the witness marks on the valve tips, it sure does not look like the valves are rotating. On some intake valves I've noticed that the valve stems (close the valve head) is polished. I thought about taking some photos, but just didn't think I could capture the details.

Does the protrusion of the rocker stud hole into the intake port disrupt flow ???

I was wondering how much this hole disturbs the flow thru the intake port. Have there been any dyno tests? It would be easy to fill with some JB Weld to make the intake port wall continuous.
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Valve spring replacement schedule ???

Id suggest that both the rate or speed of the lobe ramp design and the amount of valve spring pressure will affect the potential expected life span of the valve springs
it should be rather obvious that the quality of valve springs varies with manufacturers
it is recommended to check ALL spring pressures once a year or every 15K miles.
That does not mean they will need replacing,
that is proper maintenance. Depending on the lobes used and if properly installed, certain springs can last 30+k, some less some more.

personally I have always suggested testing every 15 k miles or about once every once a year,
and
if you find any valve springs that have lost more than about 10%- 12% of the originally listed seat or compressed load rate its time to replace the set.
most of us can,t justify purchaseing a valve spring test tool,
but most better machine shops will test them ,
if you drop them off in a box with the listed installed height, max lift and seat pressure listed for under $40-$50 for a set, in my experience


A VALVE SPRING LOAD TESTER IS EXPENSIVE, BUT A GREAT TOOL TO HAVE
vsts1.jpg

http://streetperformanceusa.com/i-72754 ... ester.html
vsts2a.jpg

http://www.summitracing.com/parts/pro-66775
vsts3.jpg

http://www.summitracing.com/parts/pro-66776/overview/
https://www.compcams.com/valve-springs-101

https://www.hotrod.com/articles/hrdp-1011-what-you-need-to-know-about-valvesprings/

https://www.enginebuildermag.com/2010/01/performance-valve-springs-and-retainers/

https://www.nhra.com/news/2019/how-pick-valve-springs-your-race-car

https://www.aa1car.com/library/valve_spring_diagnosis.htm


http://garage.grumpysperformance.com/index.php?threads/busted-valve-spring.7716/#post-38047

http://garage.grumpysperformance.co...t-compressed-when-installed.11356/#post-51869


I have roughly 15,000 miles over 5 years on the original Brodix valve springs. Is it all about the number of cycles or does time have to be factored into this equation? How often should they be changed when the lift is .560 inches. I sure don't want to drop a valve, it would NOT be worth a set of new valve springs.

Should I see more valve rotation ???
(I would not be overly worried, most valves rotate slowly during operation)

Most valves in an operating small engine rotate about the valve stem axis at varying rates. Valve rotation has an overall positive effect on valve life. Rotation provides improved temperature distribution in the valve head and a mild scraping action that cleans the valve interface of any crushed combustion deposits.
Each time a valve opens, the valve rotator turns the valve slightly. This prevents the valves sticking due to carbon build up. Additionally, it allows the inlet and exhaust valves to be heated and cooled symmetrically. ... Cleaner valves reduce engine emissions and prevent burning and guttering of the valve face and seat.


Looking at the witness marks on the valve tips, it sure does not look like the valves are rotating. On some intake valves I've noticed that the valve stems (close the valve head) is polished. I thought about taking some photos, but just didn't think I could capture the details.

Does the protrusion of the rocker stud hole into the intake port disrupt flow ???
I was wondering how much this hole disturbs the flow thru the intake port. Have there been any dyno tests? It would be easy to fill with some JB Weld to make the intake port wall continuous.

TW, remember to visually verify the stud length and cut them a bit shorter if required you don,t want the lower end protruding into the intake port and any threads doing that do NOTHING to increase the stud rigidity but they sure can reduce port flow rates if left sticking down into the air flow path
rockerstudp1t.jpg

rockerstudp2.jpg


ID ALSO POINT OUT THAT A ROCKER STUD GIRDLE ADDS A GOOD DEAL MORE STABILITY TO THE VALVE TRAIN

if the stud extends into the port ID get it machined shorter
if the lower rocker stud does not reach into the port Id be more concerned,
with the potential need to add a rocker stud girdle for rigidity than with minor port flow irregularity
p
IMG_2071.jpg

http://www.summitracing.com/parts/SUM-141010/?rtype=10
sum-141010.jpg


http://garage.grumpysperformance.com/index.php?threads/valve-spring-cooling-via-engine-oil.6491/

http://www.summitracing.com/parts/CCA-4014/
caa-4014.jpg

wrl-832010_w.jpg


viewtopic.php?f=52&t=1769

Photo0020.jpg

 
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but most better machine shops will test them ,
if you drop them off in a box with the listed installed height, max lift and seat pressure listed for under $40-$50 for a set, in my experience


A VALVE SPRING LOAD TESTER IS EXPENSIVE, BUT A GREAT TOOL TO HAVE
vsts1.jpg

http://streetperformanceusa.com/i-72754 ... ester.html

Street Performance USA must of changed their name, the link above no longer works. When I searched
on Street Performance USA, I get Pit Stop USA. They have one left of the tester shown above, better hurry
it won't last long at around $1200. :)

https://pitstopusa.com/search.html?q=valve+spring+tester

Is there a way to remove all valve springs with the heads installed so you can take them to the machine
shop for testing ? I know you can do it one at a time, but that would not be very convenient.

I don't have rocker studs that protrude into the intake port, it's just a threaded hole for the stud. Just
wondering if it would be worth filling the hole with JB Weld so the port wall is continuous ?
 
as to filling the threaded stud hole , every test Ive seen shows the risk of having the epoxy plug come loose is far greater , a risk than any insignificant increase in air flow rate
and no, Id remove the valve springs with the heads off the engine
 
OK, thought there might be a tool I wasn't aware of for removing all valve springs with the heads on.

Thanks !
I suppose you could remove the springs one cylinder at a time by putting the piston at TDC and then removing the springs for that cylinder. Then clean the valve stem and put your retainer and locks back in place and use a piece of duct tape on the valve stem beneath the retainer so that it can't slip down. Then do the same to the other cylinders. That would also keep all the pieces and parts in order.
But knowing you Rick, once you see the wear on the bottom side of the retainers and shims, you will be replacing all of your valvetrain components.
Did you ever deburr and "tip condition" your valve springs? I now do it to all of mine. Like this:
chamfer ends.jpg deburred ends.jpg polished spring.jpg

You can also buy them with this already done, but obviously it there is an additional cost.
 
It does sound like a very frustrating day when it come to re-assembling the heads. Trying to
keep the valves high enough to get the keepers in place.

Did you ever deburr and "tip condition" your valve springs? I now do it to all of mine.
Yes I did, below are the edges that I smoothed out.

ValveSpringDeburr_ID.jpg
ValveSpringDeburr_OD.jpg
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I have already put the heads together and I'm not really pushing any limits of spring durability, but next time I would
definitely want to borrow your spring checker. Thanks for the offer!
 
those , valve spring testors,
Moroso Valve Seat Pressure Testers 62390
have neither the load rate capacity nor the consistency/accuracy for use on much more than stock flat tappet hydraulic lifter valve springs
mor-62390.jpg


The following recommendations are from Erson Cams. If you have questions, you can reach their tech department at 800-641-7920.

Hydraulic Flat Tappet Camshaft: 110 lbs Seat pressure/250-280 lbs open pressure

Solid Flat Tappet Camshaft: 130 lbs Seat Pressure/300-325 lbs open pressure

Hydraulic Roller Camshaft: 130-140 lbs Seat Pressure/300- 355 lbs open pressure

Solid Roller Camshaft: (Minimum Safe Pressures DEPEND ON SEVERAL FACTORS)

Up to .600˝ valve lift: 200-235 lbs Seat Pressure/600 lbs open pressure

Over .600˝ valve lift: 250-280 lbs Seat pressure /100 lbs pressure for every .100˝ of valve lift


ValveSpringClearance01.jpg



A VALVE SPRING LOAD TESTER IS EXPENSIVE, BUT A GREAT TOOL TO HAVE
vsts1.jpg


PRO-66776_xl.jpg

https://www.summitracing.com/parts/pro-66776/overview/

pro valve spring testers used by most machine shops have an adjustable valve spring height compression stop,
and a gauge that reads that pressure at the set height
you need to know the load rate at the installed height and at max load lift,
and thats less total coil compression than at coil bind.
the MOROSO check tool will be quite helpful if your checking stock valve springs to find a defective spring,
but its just not precise and consistent enough to compare load rate loss over time
 
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Seems like I payed more than $100 for mine so I don’t know if it is more accurate than that one. Mine was recommended by a promod racer to check seat pressure after every pass when running the valve clearance check. I’m sure there are more accurate checkers out there but it would be better than nothing and free! Lol
 
Old school....................
mine LH.jpg

I adapted it to use this digital torque adapter.
HF Digital Torque Adapter.png

I wouldn't exactly call it PRECISE, but it gets the job done.
I took a spring to my local machine shop and recorded the pressures at different spring heights. I have that spring now set aside as my "calibration" spring.
S.R. & Elgin Calibration Chart.png
 
I don't remember that table, but that 36" aluminum ruler is mine.
Black plate - instructions and decimal equivalents.

Nameplate LH.jpg
 
Notice the shape of the housing - it's a bell.
There is a ramp device inside that "rings" when you reach your desired checking height.

Under.jpg
Tone Device.jpg
 
Ok, I understand now, it's a table of fraction to decimal equivalents.

What a neat tool! Don't need no stinking electronics to create a tone at height!
 
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