Are Swivel Feet Worth the Trouble?

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Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Thu Sep 15, 2016 10:28 pm

The cam I selected is an Eagle 2228 "Gas Saver" from CB Performance. I measure lift at the valve at .394" and am using 1.1 rockers. CB says the stock springs should work. If my trusty ol desktop dyno is close, this cam should be all done by about 5000 rpm.

I also bought from them the Mazda style adjusters. I made an adjustable pushrod to help get my geometry right, and think I am getting this narrowed down. At half lift my adjuster is parallel to the valve. My shim stack is about .157"- this seems a bit hi and my pushrod is a bit longer than stock. Will grinding the under side of the rocker shorten the shim stack? And If I do grind there, will that mess up the oiling of the adjuster? It would be nice to not have to buy longer pushrods.

Are the swivel feet actually worth the effort in terms of longevity as compared to good stock adjusters? The stock adjusters were pretty easy to get the geometry right.

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Re: Are Swivel Feet Worth the Trouble?

Post by Marc » Thu Sep 15, 2016 11:14 pm

Those who sell swivelfeet would have you believe that merely shimming the rocker shafts out is all that's needed to use them...no doubt they realize that if they told the truth about how much work it is to set them up right, sales would suffer.

With <.400" lift and attention to correct geometry, you shouldn't really need them. But I strongly recommend "solid" shafts in place of the stock springclip/wavy washer setup for any engine that'll see 4500+ RPM. Fresh new springs with some ~.030" steel shims underneath should be enough, particularly if you keep the valvetrain weight down by using stock adjusting screws and aluminum pushrods.

With more lift you should either use "lash caps" to increase the surface area of the valvestem tip, or swivelfoot adjusters. Most lash caps add ~.080" to the length so longer pushrods and rockerstand shims are required to correct the geometry. Generally speaking, when you go beyond .060-.090" of rockerstand shims you lose sufficient thread engagement on the nuts with stock studs (unless you back the studs out of the head a bit).

With the swivelfeet, grinding the underside of the rockerarm back provides enough room for the adjuster foot so that the ideal pushrod length/shim stack is very close to the stock-adjuster setup. For the elephant-toe "911" adjusters there needs to be sufficient clearance for them to swivel without making contact, so ideally the rockers should have recesses ground in them - with the Mazda/Courier adjusters, they need only be ground away "flat", easy enough to accomplish on the bench grinder (you'll need an m8x1.0 tap to chase the threads afterwards).

Keep in mind that each full turn of the adjusting screw changes the lash by ~.040", and you only need to grind enough off to allow for future valve adjustments...so a half-turn is sufficient, 1½ turns is ample - more than necessary but it does make it easier to slip the feeler gauge in. You want to have as much thread engagement as possible below the oil-passage "waist" of the screw, with no support there they can break right off.

You'd not be impairing the oil flow to the adjuster ball by doing this, the passage is a bit further up. Note that some stock rockers escaped the factory without getting the end of the passage drilling welded over - doesn't do any harm with stock or 911 adjusters, but don't use those ones for Mazda/Courier adjusters, you'll lose oiling to both the adjuster's ball and the rocker shaft.

Here's an example of some stock rockers nicely clearanced for 911-style adjusters (NOT for the Mazda-style since doing this unnecessarily removes threads that they need for support):
tabari 800.jpg
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Re: Are Swivel Feet Worth the Trouble?

Post by Piledriver » Thu Sep 15, 2016 11:43 pm

Either style needs relatively thick shims under the rockers to optimize the rocker geometry.
The pivot point at the valve is at the center of the ball pivot (either style) not the face of the valve as stock.
Google for "mid-lift rocker geometry" for all the why.

I'm not a fan of the Courier adjusters, but on a mild enough cam they should help guide wear if installed and set up properly. On even a semi-serious cam they will bind up due to crimping the edge of the cup if over their angle limit.
The 911 style adjusters have more range, and the ball cannot "flip over".

The Bugpack versions that go for ~$40/set are not too bad.
I always wanted some little 12 point 10mm x 8mm thread Ti nuts to go with them but I can never seem to score them at a reasonable price.
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Re: Are Swivel Feet Worth the Trouble?

Post by Marc » Fri Sep 16, 2016 12:12 am

Piledriver wrote:..I'm not a fan of the Courier adjusters, but on a mild enough cam they should help guide wear if installed and set up properly. On even a semi-serious cam they will bind up due to crimping the edge of the cup if over their angle limit.
The 911 style adjusters have more range, and the ball cannot "flip over"...
The Mazda style have sufficient angularity to handle at least .430" valve lift, if the geometry's set up right they don't come near at the edge...and if/when they do wear out enough that the ball is no longer held captive, it still can't go anywhere until the rockerarm assembly is removed. I've never seen one "flip over" in operation (that's something to watch for during assembly and possibly during adjustment, of course).

If the 911-style does break, the toe (and possibly also the tip of the screw) are loose in the engine, and by the time you're aware of the problem the remains of the screw can mess up the end of the valve stem quite badly.

The "short" 911s that use an Allen wrench for adjustment shouldn't give you any trouble with valvecover clearance, but the screw-slot style and the Mazdas will normally require some dimpling on stock valvecovers if the rockerarm is properly ground away on the underside.

In short, each style has its pros & cons, but personally I prefer the Mazda ones - folks who report trouble with them just haven't take the time to set them up correctly IMO. But, I don't have much experience with the cheap ones that are on the market these days, I preferred to buy mine at the Ford dealer (made in Japan by Mazda, came with a 12mm-wrench-size nut that was immediately tossed out). Sometimes I used aftermarket ones from Bugpack or EMPI in a pinch - their screws were softer and prone to stretching if the jam nut was overtorqued, and the balls were more prone to coming loose, but they still worked fine so long as you were aware of their shortcomings.

Over many years of hard racing use I have never had one fail me, and I don't consider the cams I used "mild". The ones on the motor in my trike have at least six seasons' racing on them and I'm not the least bit worried about breaking one, they still look fine. By design they receive lubrication via the drillings in the stock rockers, unlike the 911s which rely on splash alone. This feature makes them sort of a "poor-man's hydraulic", since oil pressure against the back side of the ball tends to keep it in contact with the valvestem, reducing clatter.

Of course I still carried spares to the track, of both types - but it was only the 911 ones that ever came out of the box...to help out the other guys ;)

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Re: Are Swivel Feet Worth the Trouble?

Post by Piledriver » Fri Sep 16, 2016 12:33 am

I usually saw a very narrow slot from the oiling groove around the screw hole to the outer end of the tip, just through the threads to provide unobstructed flow.

It's essentially an oil sprayer on a T4 if the lifter oiling grooves are widened sort of like a hydro, or if you do the HVX mods on a T1 including a flow path around the lifters, t4s have full-time pressure feed to all lifters, the oil gallery runs across the top of all 4 on each side rather than through the bores...

I think the only reason I disliked the courier adjusters is if you happen to flip a ball, when it eventually self corrects, the loud smack it makes and following loose valve train noise make you think you just broke a rocker or lost a spring.
... That and most decent T4 cams are beyond their lift limits at .500 at the valve.

The real Porsche units I have in my current engine have >150K on them across two incarnations of the engine.
Haven't had to actually adjust them in ages. The price of the 911 ones used to be fairly steep, but has gotten obscene over the last ~5 years.
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Re: Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Sat Sep 17, 2016 8:07 pm

Well, I've been fahrting around with this a couple days, and have a few observations. I really need to work on VW's more than every few years....

First off, I ground about .050 from the bottom of the rocker and was able to lower the shim stack approx .050 to around .120" and was able to use a stock pushrod. This gave me about 1 1/2 thread adjustability on the Mazda adjuster. Damn, this is hard to do while the wife is watching the first Die Hard... and every other sentence the type spuriously goes someplace else... running Linux Mint 17.3 if anyone knows something.... aaargh!!!!

Now, back to the business at hand...

I think the adjustments will work ok. I believe the pivot ball will be fine. Plenty of clearance to the "Ball Holder" at full stroke. I don't think the ball could ever flip if the valve adjustments are even close. But- as I was worrying bout before, the oiling of the adjuster- is pretty close to being choked off.
Well, this is the first time I tried posting a pic, i'm going to send it as is to see if it works. Should show about how close the oil hole is to the welded up passage on the rocker.

https://www.facebook.com/photo.php?fbid ... =3&theater

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Re: Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Sat Sep 17, 2016 8:22 pm

Well the picture posting didn't quite work as expected, but the link to it did work.

Another thing I noticed is that in stock form, the oiling of the new ball would be minimal- think about it-
look at this rocker, sorry about the link-

https://www.facebook.com/photo.php?fbid ... =3&theater

Theoretically there is 40 -60 psi on the system with some loss at the lifter, some more loss at the pushrod, more loss at the rocker cup, more loss on the stock rocker shaft or solid shaft and shims. Then what pressure is left over's got to go thru the other side of the rocker to the adhuster ball. That just doesn't sound good to me.

I did notice that some of the solid rocker shafts looked like they machine a groove for better oiling. But if a guy was to retain the stock shaft, couldn't a guy take a dremel tool and grind a slot between the two holes on the shaft for better oiling?

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Re: Are Swivel Feet Worth the Trouble?

Post by Marc » Sat Sep 17, 2016 8:34 pm

Are you planning to drill/tap the ends of the stock shafts to convert them to "solid"? The stock springclip/wavy-washer setup will let you down before 5000 RPM.
I wouldn't fret over the volume/pressure of oil making it to the adjuster balls, so long as they aren't run dry. The ones you're working with are decidedly thicker at the ball housing than I'm used to - looks like you can't grind as much off of the bottom of the arm before the upper threaded section of the screw engages the arm. I wouldn't want any less than two threads working, enough to take the stress when you cinch down the jam nut.

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Re: Are Swivel Feet Worth the Trouble?

Post by Piledriver » Sat Sep 17, 2016 8:35 pm

You can groove the shafts or use a small ball mill to groove the rockers, groove around the top as thats not really loaded.
Big Ratfink wrote: and every other sentence the type spuriously goes someplace else... running Linux Mint 17.3 if anyone knows something.... aaargh!!!!
On a laptop?
The ones with big touchpads take some getting used to...
My son used to tape a bit of thin cardboard like a cereal box over the touchpad...
I have X-series Thinkpads and simply turn the touchpad off, and only use the touchpoint.
(My X200T there is no issue as it ONLY has a touchpoint, and an awesome keyboard)

There's usually a software setting to disable the touchpad while typing, but usually its a matter of learning to type while only touching the keys.

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Last edited by Piledriver on Sat Sep 17, 2016 8:37 pm, edited 1 time in total.
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Re: Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Sat Sep 17, 2016 8:37 pm

Image

HA! I learned something!

Image

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Re: Are Swivel Feet Worth the Trouble?

Post by Piledriver » Sat Sep 17, 2016 8:41 pm

Once you get it all sorted, you're going to need to dimple the valve covers and/or shorten the screws a bit, put a new slot in with a dremel tool and a reinforced cutoff wheel.

One usually needs to shim the rockers UP to get the geometry correct, the "stock pushrod fits" is not the right unit of measurement, though it may be convenient.

Google for "mid-lift valve geometry" for an explanation of what you are attempting to do, and why.
Your valve guides will last a LOT longer if done right.

http://www.aera.org/technical-articles/rocker-geometry and
http://www.mid-lift.com/INTRO-TECH.htm is a great start.
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Re: Are Swivel Feet Worth the Trouble?

Post by Marc » Sat Sep 17, 2016 8:45 pm

And notice the little "bump" on the side of the rockerarm that's been running against the slot in the rocker stand. That's how thick the whole arm was when new. The bump needs to go (by surfacing the side of the rocker till it's level). It'll bang into the slot with more lift than before – or just from changing the geometry – until it wears away more. Can make mystery valvetrain noises until it does, and it's better not to have that metal in your oil. You can do a fairly good job of surfacing the rocker just with a sheet of wet-or-dry sandpaper along the edge of a sheet of glass. ~320 grit (kept flooded) is fine enough and won't take all day.

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Re: Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Sat Sep 17, 2016 8:51 pm

I will order a solid rocker kit with extra shims. I think this is cheap insurance..

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Re: Are Swivel Feet Worth the Trouble?

Post by Big Ratfink » Sat Sep 17, 2016 9:02 pm

Yup, I know the little "bump" on the side you're talking about. One set I have is like that. The set I am using looks smooth.

The last Chevy I did I used Miller Mid Lift Rockers, thought it was a good idea. One of the roller tips didn't last1 hour of run time. I was PO'd. probably my fault, might have overlooked something.

Also on the shopping list is some .120 shims from CB. This is about the shimstack that worked right for parallel adjuster at mid lift with stock pushrods.

Thanks for the heads up on the potential rocker / valve cover clearance issue. I am a believer in stock valve covers and can work some magic to make it all fit.

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Re: Are Swivel Feet Worth the Trouble?

Post by Piledriver » Sat Sep 17, 2016 9:06 pm

A ball peen hammer works wonders.

If you forget or don't give it enough extra to allow for the gasket to compress per usual, the screws will pound holes in the valve covers.... At least ist's a good guide where to give it more clearance.

...also note for your geometry calculations that the valve side pivot point is in the center of the pivot ball, not at the valve face like the stock adjusters---sort of like the roller rocker examples shown in the links.

To get back to ~stock rocker geometry (dangerously assuming that's right with the new cam) you are looking at raising the rocker shaft 2-3mm. (~half the diameter of the pivot ball or thereabouts)

I would be amazed if it was "right" with stock pushrods unless the heads were seriously flycut to raise compression.

(EDIT---OK, we're on the same page)
Last edited by Piledriver on Sat Sep 17, 2016 9:11 pm, edited 1 time in total.
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