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katalla Mon May 08, 2006 1:55 pm

if you keep the crank stock sized 69mm, then can you just use stock pushrods and not worry about geometery, since the engine width is the same?
btw im thinking for like a 1914 engine

mharney Mon May 08, 2006 2:33 pm

What's going to happen when you change the cam? Give it a think.

katalla Mon May 08, 2006 3:36 pm

yeah it makes sense now that the lift would be greater so it wouldnt be the same at half lift, for some reason i didnt think about that hehe,

gerg Sun Oct 08, 2006 12:32 pm

mharney wrote: What are those, 1.25? Is that half lift?

Those rockers will have to be cut down to get your geometry right, I think. Look at how high they ride on the valves. Look at how much you have to have the adjusters out to be close to the right angle.

Where do you actually machine the rockers? The face of the tip closest to the valve stem? Allowing the stem to screw in farther, hence the rocker rotates more into a parrallel position at 1/2 lift?

What will happen if the rockers are horizontally just off center as described in this post, but vertically a bit high? Would it be inefficiency in the valve train, or most likely broken parts?

mharney Sun Oct 08, 2006 2:12 pm

Yeah, you want to machine the valve side of the threaded head.. the side that the elephant or swivel adjusters must start screwing in from when you install them on the rockers. This makes it so that the head can be closer to the rocker arm.

Desertbusman Fri Oct 13, 2006 12:28 pm

Quote: Was attempting to get my rockers and adjusters set up tonight but ran into a snag.
It seems that to get the geometry reasonable I'll be using stand shims and probably grind a bit off of the swivel ball side of the rockers. With the adjusters turned all the way into in contact with the rockers I stilll don't get any valve clearance. But even now with the adjusters screwed all the way into the rockers it looks like the oiling holes are allready past lining up. With the adjusters out a couple turns oil passage would line up to lubricate the ball. To grind off the rockers, say .020-.040", the oiling will definately be blocked. In comparing these swivel ball adjusters with another brand I don't see any difference in dimensions of the oil inlet groove. And the rockers are German stockers. Any suggestions???

Another question of less concern right now is valve rotation. I have the swivel balls offset a bit to the side of the valves centerline as is discussed in the geometry sticky. But with the balls free to rotate in their sockets will they actually be functional in rotating the valves? I can see how a standard solid adjuster will rotate the valve but with the ball not being solid will it rotate the valve?

Stock 1600, stock springs, Engle 100, solid rocker shafts, stock rockers, and questionable swivel ball adjusters.



I hear about grinding the rockers but I don't hear about the oil hole. What's up? So temporarily I put in stock adjusters. Why does VW have that oiling provision at the adjuster threaded hole on stock rockers and yet the stock adjusters block the oil hole? Where do the valve tips get lubed from?

gerg Fri Oct 13, 2006 12:35 pm

I ground the tips last night, removed ~.1", here is the result. Since the 911 adusters don't have the oil hole there was no reason to worry about lining it up. Rocker on left was ground:


buggpower Sun Oct 15, 2006 9:06 pm

Guys, I'm just curious but has anyone ever ran the stock cam with like 1.25:1 rockers, or would that work? :?:

mharney Wed Oct 18, 2006 5:38 am

Desertbusman wrote: I hear about grinding the rockers but I don't hear about the oil hole. What's up? So temporarily I put in stock adjusters. Why does VW have that oiling provision at the adjuster threaded hole on stock rockers and yet the stock adjusters block the oil hole? Where do the valve tips get lubed from?

Mostly it's splash. I don't think much manages to see out the adjuster threads, but probably some. When the nut has the stud tightened against one wall of threads, it might be that there is enough passage for oil to drool out of the rocker.

novetti Wed Nov 22, 2006 11:40 am

I have the same doubt as bugpower:
did anyone have experience using a 1.25:1 rockers with stock cam?
Is it a no-no? Difficult to adjust rocker geometry with this setup?

Thanks in advance,
Julio

john@aircooled.net Thu May 24, 2007 10:05 am

.410 lift is with 1.1 rockers. With 1.25s it's

(.410/1.1)*1.25 = .466"

So 1/2 lift is .233, still pretty close to 1/4"

John
Aircooled.Net Inc.

COBussmuggler Mon Oct 29, 2007 10:53 pm

Desertbusman wrote: Quote: Was attempting to get my rockers and adjusters set up tonight but ran into a snag.
It seems that to get the geometry reasonable I'll be using stand shims and probably grind a bit off of the swivel ball side of the rockers. With the adjusters turned all the way into in contact with the rockers I stilll don't get any valve clearance. But even now with the adjusters screwed all the way into the rockers it looks like the oiling holes are allready past lining up. With the adjusters out a couple turns oil passage would line up to lubricate the ball. To grind off the rockers, say .020-.040", the oiling will definately be blocked. In comparing these swivel ball adjusters with another brand I don't see any difference in dimensions of the oil inlet groove. And the rockers are German stockers. Any suggestions???

Another question of less concern right now is valve rotation. I have the swivel balls offset a bit to the side of the valves centerline as is discussed in the geometry sticky. But with the balls free to rotate in their sockets will they actually be functional in rotating the valves? I can see how a standard solid adjuster will rotate the valve but with the ball not being solid will it rotate the valve?

Stock 1600, stock springs, Engle 100, solid rocker shafts, stock rockers, and questionable swivel ball adjusters.



I hear about grinding the rockers but I don't hear about the oil hole. What's up? So temporarily I put in stock adjusters. Why does VW have that oiling provision at the adjuster threaded hole on stock rockers and yet the stock adjusters block the oil hole? Where do the valve tips get lubed from?

The holes in the rocker arms are for lubing the rocker shaft. If those aren't lined up with the holes in the adjuster screws, the shafts will gall. Oil comes up the pushrod to the adjuster screw through the rocker to the shaft.

gerg Mon Oct 29, 2007 11:21 pm

The hole in the adjuster screw is after the point of oiling the rocker shaft.

Oil to Pushrod --> rocker shaft --> Rocker adjuster

I am curious about why the oil holes were there because of that pecking order.

I am running 911 adjusters from John at AC.net and they do NOT have the holes in them at all.

I have several thousand trouble free miles on my engine with there. No galling of the shafts yet.

I guess the hole helps oil get into the thread area of the adjuster and seep out to lube the tip of the adjuster / valve stem?

redhot Wed Dec 12, 2007 5:10 am

The Scat style rockers have the adjustment on the pushrod side. What should I line up with the valve-stem, since I have no line to draw through the adjuster screw. Anyone got a picture like in the start of the thread?

Also: why is it designed so? To have less wear on the valve-stem?

Appreciate your replies!

Notched Sat Feb 02, 2008 4:39 pm

Same question here. I have the adjusters on the push rod side. Is the angle of the adjuster as critical with the Scat style rockers?

cootes Sat Feb 16, 2008 6:18 pm

X3 - I've got swivel adjusters on the push rod side too!

Is the goal to have a straight adjuster when properly shimmed, or am I trying to get the contact point, rocker to lash cap dialed in with shims?

p.s. Does the height change, in moving the contact point, change the effective ratio? Get out your slide rules...

veedubnut Thu Feb 28, 2008 5:43 am

Wow! I was redirected here from a post I made concerning a 1600, stock cam, stock heads, and wanting to install 1.4 ratio rockers...I can't beleive a guy who puts together a stocker has to go through all THAT just to use 1.4's...seems rediculous. Now you guys building all sorts of power with all sorts of aftermarket parts and what not, I can totally see how this thread would be instrumental in getting your rocker geometry set to work right with the parts you have chosen.

But back to the stocker. I mean aren't 1600's built basically the same? I mean with using a stock crank, rods, pistons, heads, and valves, the stock pushrod length should be....what? (I don't know off hand). But it stands to reason that all stock pushrods are the same. And since nothing is changing except the rockers, there must be a "tried and true" length spec when switching to 1.4 rockers from the stock 1.1's on an otherwise bone stock motor. You know, the ol..." oh you're using those? you need to make your pushrods [x amount] shorter." I mean there HAS to be a tried and true length out there to tell me what my pushrods need to be when using a stock crank, conrods, pistons, heads, and valves and want to go to 1.4 ratio rockers. Right?????

mharney Thu Feb 28, 2008 8:23 am

No, there doesn't have to be. There are variables. Reground cams, deck height, rocker spacers, rocker mfr, you name it.

With that said, john at aircooled.net sells pushrods set up for 1.4 on stockers, and he gets in the ballpark (close) with them.. perfection is relative, and the rest of your valve train will affect how critical it is.

You can go cheap and easy, or you can go right. You choose.

Max Welton Thu Feb 28, 2008 12:15 pm

These days even a stocker has been around long enough to have been rebuilt several times, sometimes because they wore out and sometimes because something broke. The case may have been decked. The heads may have been fly-cut. Both of those change key dimensions that affect the geometry.

I checked my stocker when I gave it a top-end rebuild even though I was using all stock (rockers included) components. It wasn't perfect, but it was very close and I elected to just run it.

Max

mobius:py Wed Apr 09, 2008 12:25 pm

hi masters

i buy rockers 1.4 , but my cam is a engle 100...

definitely not work?? :cry:



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