1679 Engine Build - A First-Timer's Tale

[NewTechnicIan]

OK I might have found someone locally who can cut my heads, I'm going to talk with them tomorrow. I'll find my deck height tonight. For now, here's my cam card.

That cam, L3 heads, 34pict3 carb. 8:1 compression.
I'm hoping this will keep me somewhere between good power and mileage without having to buy premium gas all the time.
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[NewTechnicIan]

OK, So I checked my deck height last night using some sockets to hold down the cylinders.

New Deck Height Numbers:
#1: .059"
#2: .055"
#3: .059"
#4: .056"

So while there was a difference, it was more on the order of 1-2 thou than something super substantial. But I'm glad I checked. Now I've used CB's engine calculator to get that my heads should be taken from ~59cc as advertised on ACN to 51cc for my 8:1 compression. I'll be bringing the heads by a machinist today to see if they'd be interested in the work.

Oh, does anyone know if I'm getting my heads flycut for less combustion chamber volume, do I generally also need my cylinders machined down at all? And by that I mean the shoulders of the cylinders, not the mating surface with the head. Hope that makes sense.
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[GraysonM]

No, you shouldn't need to do anything, but on higher lift cams, flycutting the heads significant amounts requires careful checking of valve to piston clearance.

The other option is putting in a stroker crank! Then you don't need to flycut the heads. A quick calculation shows that a 78mm crank would put you at exactly 8:1 on the lowest cylinder.

As I was calculating the deck height and compression on my engine and how much I needed to reduce the compression chambers, I realized that I was dealing with all the headache of building a stroker engine without getting any of the benefit of added displacement.

Depending on the machine shop and how well equipped they are to do the job, you may wind up paying them close what it cost for a new crank.

Something to consider.

[NewTechnicIan]

Hi Grayson,
Interesting idea on the crank. Maybe I'm confused but then wouldn't I need stroker barrels or different con-rods for the pistons? Otherwise I'd end up with way negative deck from all that extra stroke, right?

Anyway, Aircooled.net is willing to do a swap on the heads so I think I'm just going to send them back and get ones that are cut to the right depth. I just wish there were a VW shop around town ! It would make these mistakes so much more minor. Ah well
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[NewTechnicIan]

OK, got my heads back from ACN, and the machine work looks good! Spent some time last week working on them.
Took out the valves:

Tried using permanent marker for a Dykem substitute, didn't work:

Lapped the valves in:

Sanded down my valve retainers to hold the stem tightly:

Sanded til I could see daylight between the retainers:

I don't really have the tools to fluff and buff the heads or check the displacement but the machine work looks consistent and the prep on the valves while I was taking the heads apart looked thorough.

Any further suggestions on a newbie checking out his heads before I clean and grease everything back up and get ready to assemble the long block?
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[Dr OnHolliday]

You dont need dykem for checking valve seating - what you are really looking for is the matte gray where the valve and seat have been lapped together, a solid ring of gray on each part....
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1965 Type 1 sunroof Baja / about 70k miles on self-rebuilt '74 1600 and counting / SP heads and aftermarket valve keepers / non-doghouse shroud with external cooler and filter / 1.5 qt extended sump / Weber 32/36 DFAV progressive carb / 009 dist with Pertronix / 1.25 ratio rockers and ball adjusters / 1.5" stainless steel J-pipes and carbon steel baja exhaust

[Dr OnHolliday]

Damn phone
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1965 Type 1 sunroof Baja / about 70k miles on self-rebuilt '74 1600 and counting / SP heads and aftermarket valve keepers / non-doghouse shroud with external cooler and filter / 1.5 qt extended sump / Weber 32/36 DFAV progressive carb / 009 dist with Pertronix / 1.25 ratio rockers and ball adjusters / 1.5" stainless steel J-pipes and carbon steel baja exhaust

[NewTechnicIan]

Ok Great. So the valves already came with that dull ring on them but I guess they've just been double-lapped.

See what you think:

So like I said, the work on the heads looks good, I'll not be doing any fluff-and-buff work and I don't think I'll be doing much with match-porting the heads to the intakes. Maybe when I go for my next engine

Been cleaning up engine tins and things when I've had some time, getting ready for the next few steps ahead. I'll clean the heads up in the next couple days, reassemble those, and I think I'm ready for assembling the long block.
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[Dr OnHolliday]

^^^ that's exactly what you want to see (seats too)
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1965 Type 1 sunroof Baja / about 70k miles on self-rebuilt '74 1600 and counting / SP heads and aftermarket valve keepers / non-doghouse shroud with external cooler and filter / 1.5 qt extended sump / Weber 32/36 DFAV progressive carb / 009 dist with Pertronix / 1.25 ratio rockers and ball adjusters / 1.5" stainless steel J-pipes and carbon steel baja exhaust

[NewTechnicIan]

Awesome, glad to hear it. I cleaned everything up this weekend, oiled the valve guides and reinstalled the valves so the heads are ready to go.

Final clean of the other parts and assembly of the long block is nigh!
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[NewTechnicIan]

Well I wanted to make sure of my rocker geometry before I started assembly so I could be pretty confident in all this stuff and build the long block quickly and start it up within a couple days of bolting it together.

I screwed something up of course

While I was mocking up the crank and cam and followers to start looking at the rocker geometry I pinched two bearings. Ugh, I guess that's what I get for not thinking about engine stuff in a while and running through steps

So I guess I'll need a new bearing set and lesson learned. For now the engine actually rotates fine when I put the crank onto the correct dowel holes so I used it to start checking valve geometry.

Since I'm using swivel ball valve adjusters I needed to grind down my rockers to accept them and still have clearance.

Before:

After:

A couple pictures of the oiling holes too:

I used the shims that came in the pack with the adjusters, they were .030" each, 8 total. That gives me .060" shims under each pedestal.

So I bolted on the rocker assembly to see what that got me. It turned out I either needed to take more off the rockers or shim the assembly higher! The assembly bolted down and already had started pushing valves even at TDC. I'm using stock push rods and I don't think anyone uses shorter than stock push rods (Right?) so I don't think that's where I want to adjust it.

Check out the pics below, I'm looking for advice on whether to shim higher or grind the rockers more.


Excuse the crappy pics, the lighting could be better in the basement.

Zero Lift:

Half Lift:

And with the Geometry lines:

Full Lift:

From this, I'm thinking shims will be the answer? I know at zero lift I need the adjuster side to be higher so that I can adjust it at all. The shims would fix that and would (I think) Fix the acute angle I'm seeing at half lift on the pushrod side?

There's a thousand of these threads but I haven't been able to find any pictures of people's ground down rockers to compare my own! Anyone's help would be so appreciated here!

Thanks!
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[Brian_e]

From where I am sitting, it looks like removing the shims and maybe removing some more of the underside of the rocker would get you just about perfect. I usually cut about .100" off my rockers.

You want your no lift and full lift to be very similar angles, while keeping your half lift in line with the valve stem. Right now you don't have much angle at 0 lift, but a bunch at full lift.

Here is what I do.
Use an angle finder and set the valve cover rail at 9.5° (angle of the valve center line relative to the head). This will make your valve stem 0 or 90 depending on how your angle finder is held. Now you can rig up a way to measure the angle at zero and full lift. You will also know when your half lift is zero as well. I have used a 2" long thin steel strip with a 8mm hole at one end. Put the strip under your adjuster nut and tighten it down. Set your angle finder on the strip.

It will take a bunch of fiddling around, but I think the angle finder makes it much easier to visualize whats changing.

Once you get your geometry all figured out, don't forget to check the oil hole in the threaded adjuster shaft. It might need to be slotted some to realign with the oil hole in the rocker arm.

Brian

[NewTechnicIan]

Thanks for the tips Brian,
So a little more research has turned up that, indeed, shorter than stock pushrods are an option in building engines with these adjusters. I found a thread talking about the geometry problems here:
Right Here

So I guess I'll chop up a pushrod and make an adjustable to start fiddling with this. Updates to come
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[calvinater]

Howdy, Any updates?
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"Albatross"!

[calvinater]

Howdy, Any updates?
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"Albatross"!

[NewTechnicIan]

Howdy! Finally got to work again. Little steps forward as we start to defrost up here.

I Think I have my valve geometry set! Take a look-see at the following pictures. I did my level best to get my dial indicator in the correct orientation and position of the valve stem for accurate measurement.

I tried assembling without shims and used my home-made adjustable pushrod, and the results were good but the adjusters were screwed ALL the way in. So I screwed out the adjuster 1 full turn just in case and that changed things enough that I needed to add a .03" shim to the rocker pedestals. That seems like it's all I need, the contact patch is nicely centered and the adjuster is in line with the valve at half lift, at least to my eyes. Full lift looks a little more extreme than 0 lift in the picture but I took the pictures from a slightly different angle and I think that's where it looks a little off.

See what you think!

Zero Lift:

Half Lift:

Full Lift:

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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[clonebug]

I have a set of DRD heads and they are at 52 cc's on the chambers.

I ended up getting CB's Swivel feet and I ground my rockers down to make clearance.

Here is my build page with the specs I used.

http://www.shoptalkforums.com/viewtopic.php?f=3&t=127936&start=1335

I used .131 inch of shims and the stock pushrods to make everything work.

Keep going to the next page for the actual final results .
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[NewTechnicIan]

Hi Clonebug,
Nice work. I like your methodology from your thread, especially checking total lift as a good measure of how spot on your geometry is. It wasn't explicitly mentioned in a lot of threads I've seen but it makes a lot of sense that you'd want to have the exact valve lift that the cam says it has!

When I checked the total lift this morning I had .336" instead of .344" so I guess I still have some fiddling to do, although maybe that's something to do with the dial indicator. I'll have to check my setup thoroughly.

I ground my rockers down to make room for the ball bearing adjusters a while ago, and I know the contact patch is nice and wide between the adjusters and the valve stems. They won't present some of the marginal-contact problems I've heard about from some users.

Thanks for the help!
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.

[clonebug]

I got pretty frustrated doing my geometry and I probably still didn't have them perfect,
After not touching them in about 3000 miles there were no problems and they stayed quiet and almost right on adjustment.
I found a couple just a tiny bit loose but otherwise they were nice.
Just make sure you have the flat of the ball on the valve when you put the rockers back on.
It's easy to get them in the wrong spot. I pulled one rocker off to replace a pushrod guide.

I think I turned the adjusters out 1.5 turns and then used the shims and stock pushrods.

You could try that position to see if yours work out.
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[NewTechnicIan]

OK I think I have it figured out although I'm a little frustrated at what appears to be good geometry. For some reason I really can't get more than .338" lift when the card says .344". I shimmed up to .12" and down to 0" and no difference. My geometry looks great though, as I'll show you now.
I ended up shimming up to .09" on the rocker bases to get the adjusters in a good position with a few threads showing and to get the swipe pattern centered on the valve stem. See what you think.

Zero Lift:

Half Lift (with geometry lines showing I think great alignment):

Full Lift:

Swipe Pattern on the Valve Stem

I think the swipe pattern shows that I'm pretty much on the money here, knowing that all my other ducks are in a row. Feedback is welcome!
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My 73 Standard build - It's painted! It drives under its own power! Time to get it wired and upholstered!

My 1679 Engine build.