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Sun May 04, 2008 7:37 pm

Any pictures of good geometry for the 1.4's/adjuster on the pushrod side style rockers? If I remember right I want the push rod straight in line with the adjuster at half lift, ya? I've never set up this style before so don't know exactly what to look for, like angles at no lift and full lift? I'm using a dial indicator to measure half lift, works perfect.

I have the old Sig Erson rockers with a FK-44 and coming up with .560 lift, 1.43 ratio, with the pushrod straight in line with the adjuster. I actually thought these were suppose to be 1.5's but not sure how to achieve .585". Sound good?

Mon May 05, 2008 6:15 am

Anybody?

Guess nobody see's this post since it's up in the sticky section...I know I overlook these all the time.......

Sat May 17, 2008 5:33 pm

Bummer nobody sees or responds to this thread anymore.....I had to PM another member (Mharney) and he was nice enough to help me out. Another person posted a question, with pictures even, then removed it because no one responded.

Sat May 17, 2008 10:50 pm

Probably a lot of folks read it but didn't waste time answering something they didn't know about. That's good. The bad situation is getting advice from those that don't know what they are talking about. As far as your rockers- sorry, but I don't know squat about them.

Sun May 18, 2008 7:11 am

Yeah, I rarely look at these, because they are the same topics over and over, and I skip straight to the section under. If they could integrate with the other messages when there is a change in them, or just all be in the same listing, that would help some I think. Then if someone wanted to view stickies, a link to them all independent of the regular topics would be a good idea.

Mon Jun 02, 2008 4:24 am

Desertbusman wrote: .... The bad situation is getting advice from those that don't know what they are talking about. .

When it comes to VOLKSWAGEN valve train geometry, bad advice is virtually guaranteed, especially from all those 'experts.' With a horizontally-opposed engine you have to start at the parting-line and work out. You can't assume the crank & cam bores are precisely on the center-line, nor that the decks are of equal height. Any error here -- and I've seen up to sixty-thou on a poorly overhauled crankcase, gets built-in.

Ditto for cam-lift. Base-circle to peak may be fine for an individual lobe but the ACTUAL lift is based on the center-line of the cam, which can be a few thou off IN ANY DIRECTION, especially on cheap, after-market cams. Then comes dialing in the cam. Even with all stock parts ithe assemblage can be off as much as +/- 4 degrees, which is why Volkswagen provided offset Woodruff keys to adjust the frequent stack-up errors that occur in serial production. Then they provide NINE different sizes of cam gear to ensure proper mesh & timing.

Only when you've done all that basic work, ensuring you have an accurate lower-end, can you address compression ratio and valve train geometry. But by that time all the 'experts' are telling the newbies that none of that 'techy' stuff matters. And the odds are, most of the newbies will agree.

My point here is that there really isn't much a professional engine-builder can do for a newbie trying to line-up his rocker arms because not one in a thousand has done the required foundation work and most don't even have the necessary tools. Plus you have all those Instant Experts who have never done any of that stuff and their ONE engine runs jus' fine. Of course, you never seem to find any of those 'experts' at the finish line getting a champagne shampoo. Nor the flight line, celebrating a thousand trouble-free hours of flight in their RF-4D.

What you DO see is a lot of instant experts passing out bum dope by the bucketful, parroting procedures meant for water-cooled, mono-block engines that address only the OUTPUT-side of the geometry equation. In the water-cooled world the INPUT-side of the valve train geometry equation almost never changes, unless they deck the block or mill the heads more than .040. But when you build a veedub from after-market components, you've got to start at Ground Zero.

It should come as no surprise that trannies and differentials get the same treatment by all those instant experts. Indeed, newbies WANT to believe all the Quick & Easy myths, and after all, the thing DOES run. Since the odds of having to go head-to-head with a properly built engine are about the same as for finding lips on a chicken, the newbies are happy (for a while at least) and the Instant Experts give themselves another pat on the back.

Hell of a good joke, when you think about it :-)

-Bob Hoover

Sat Jun 07, 2008 6:48 am

I'm no expert when it comes to building engines. I've built a few that are still running after 5 years.The biggest part is SLOW DOWN. Pay attention to what you are doing.If you move the rocker arm .004 to the right, is that going to center it on the valve stem or put it off center? I built a 2401 IDA motor with dual Chevy spring, big ports,1.4 rocker,K8, etc, and had no trouble setting the geometry.The engine was somewhat hard to turn by hand and when the exhaust valves were about to close the engine would want to rotate due to the excessive spring pressure. The cure???? A flywheel lock. No problem.

Wed Aug 06, 2008 7:13 pm

How common is it to have to shave material off the bottoms of the rocker pads (from the rocker arm assembly) in order to achieve the correct geometry?

I'm setting up my rocker geometry on a new 2332 and can't seem to get it anywhere close in all the usual places (i.e. pushrod to cup @ 1/2 lift, wear pattern on the lash cap, imaginary line through the rocker shaft up to the top of the valve). The rockers need to be positioned further down into the head for everything to line up.

Just curious if anyone else has dealt with this.

Thanks!
:wink:

Wed Aug 06, 2008 7:20 pm

Are you using stock length push rods?

I would expect on a stroker you would use custom length push rods - so you use a tool to measure what you need, then make the push rods the length they need to be.

So instead of the base sinking in, the push rod sticks out farther to level the rocker.

Sorry if you know all this already.

I had to go that route on my 2276.

Wed Aug 06, 2008 7:38 pm

gerg wrote: Are you using stock length push rods?

I would expect on a stroker you would use custom length push rods - so you use a tool to measure what you need, then make the push rods the length they need to be.

So instead of the base sinking in, the push rod sticks out farther to level the rocker.

Sorry if you know all this already.

I had to go that route on my 2276.

I've been mocking it up using an adjustable pushrod. Basically when I set the pushrod length with a loose "zero" lash and roll the engine over I note the following:
1. The wear mark on the lash cap is very high (not centered) which suggests to me that it will push the valve in the guide "up" and wear it out prematurely.
2. Full lift is significantly higher than spec.
3. At half lift the pushrod and adjust cup are still angled (not straight)
4. At half lift the center of the rocker shaft isn't lined up to the top of the valve (if you were to draw a line through them).

These seem to be all the "tricks" to check for. Adding shims or otherwise making things "longer" makes it worse. So for me, it appears that I need to get the rocker shafts deeper into the head to realign the rocker to the valve, and shorten the pushrod.

So, you machined off some material off your rocker pads? How much?
8)

Wed Aug 06, 2008 8:09 pm

Actually I had to use a small shim - can't remember what size.

So no different length of the adjustable push rod makes things any better for you?

What rockers are you using?

Are you using swivel head adjusters?

I removed about 1/10" off of the valve side of the rocker (where the adjuster screws in) to make room for the swivel foot. Would have needed more shims without doing that and wanted to minimize the shims.

I think I posted something here although all my pics are gone.

John over at AC.net agreed with what I did, actually suggested it if I remember correctly.

All my photos are at http:\\gregblakeney.smugmug.com

Volkswagens -> 1960 Singlecab -> 2276 build

You should find some pics there of the rocker modification I did.

Wed Aug 06, 2008 8:54 pm

wardvwracer wrote: How common is it to have to shave material off the bottoms of the rocker pads (from the rocker arm assembly) in order to achieve the correct geometry?

I'm setting up my rocker geometry on a new 2332 and can't seem to get it anywhere close in all the usual places (i.e. pushrod to cup @ 1/2 lift, wear pattern on the lash cap, imaginary line through the rocker shaft up to the top of the valve). The rockers need to be positioned further down into the head for everything to line up.

Just curious if anyone else has dealt with this.

Thanks!
:wink:

Lemme guess.. Scat rockers?

Thu Aug 07, 2008 3:04 pm

Mark & Gerg,
I'm using a set of gently used Autocraft 1.4's. I've previously installed these on another engine and they measure out at 1.4.

These rockers are similar to Scat, CB, etc., in design in that the adjuster is on the pushrod end.

Mark, what's the deal with Scat's?

Thu Aug 07, 2008 5:33 pm

They're different from Berg and CB's rockers in how they line up and what they need. It appears that they are set up to work with longer stems they way they align with the stem's tip.

Sun Nov 02, 2008 11:02 pm

can you do this on a stock engine and if so, will it help the gas mileage?

Mon Nov 03, 2008 6:56 pm

Do what? Check / set the valve train geometry? Or install 1.4 ratio rockers?

Max

Thu Nov 27, 2008 10:52 am

I have a question about the need to replace Rocker Studs. My 1.25 to 1 rocker arm kit came with new rocker studs. Is it really necessary for me to remove the studs out of my new 044 heads and use the rockers studs they provided?

Thanks!

Thu Nov 27, 2008 5:17 pm

I've found the stock studs are not long enough for the 1.25 rocker blocks. I have to do the same thing. I've been advised that the stock rocker studs are lock tited and require heat to remove. I'm going to try a propane torch. I've heard of people welding a bead onto the stud to heat it up and give something to grab with vice grips.

Thu Nov 27, 2008 6:48 pm

I run 1.25 rockers on the normal studs in the 044 head and a solid rocker shaft kit from another company.

Never changed the studs. Used the blocks that came with the solid shaft kit.

About a thread sticking out?

Thu Nov 27, 2008 6:54 pm

Bob Hoover wrote:
Ditto for cam-lift. Base-circle to peak may be fine for an individual lobe but the ACTUAL lift is based on the center-line of the cam, which can be a few thou off IN ANY DIRECTION,

-Bob Hoover

True true . . I had to cut different length push rods for each side of my case. I can only presume the cam bore is not perfectly centered in the after market aluminum :( case . . . Whether it be poor case work or a base circle problem on the cam.