Rob's Motor and Bus Build

[Cdn17Sport6MT]

What I want to acknowledge here is Clatter's comment that the Len Hoffman heads are as expensive as they are, because his work with the AMC cores (which have to have the cpts removed and thrown-out) is, indeed, labour intensive. Clatter's comment is that Hoffman is NOT gouging buyers with his pricing scheme. Fair enough. This Type IV engine, simply put, is far from a cheap engine to build. Others have said that it represents a relatively poor value quotient when it comes to power- or torque per $ spent. Now I have no desire to convert to Subaru power, but obviously these considerations do provoke thought about going down that route.

Me, my question(s) really surround whether, if in the perhaps unlikely circumstance that my OEM 40,000 mile 2.0 litre heads are found to be uncracked (at least by inspection including dye penetrant inspection, albeit with OEM seats left intact) - whether they're viable to carefully run, maximizing all of the care steps outlined above.

[skills@eurocarsplus]

[Cdn17Sport6MT]

I didn't realize the stock heads would drop a seat without being overheated... That would change the equation... When you come to think of it, indeed if that's the case, well though VW's offering of the Type II for sale is many years in the past, it could be said that it was a flawed product, if it's that fragile.

[SGKent]

Type 1 heads were not prone to seat drop, or even dropped valves once the oil cooler was moved behind #3 and the heat shed elsewhere. Type IV engines started as a 1.7L used in light cars. It was adapted to buses after Porsche modified it for the 914-4 and 912e. The VW bus is nothing more than a utility truck. The kind that is used around town. The 2L engines generate way too much heat for the cooling on the open highway, but we do our best to mitigate it. It was never meant to be a 250,000 - 300,000 mile car like those built today. The whole basis of a water cooled conversion is that the engine never has an opportunity to get as hot as our engines do, even what we consider cool for an air cooled engine. If that risk and cost seems too high, get another vehicle for your daily driving.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Cdn17Sport6MT]

I've owned my '79 Kombi for 41 years; I'm not about to sell it, LOL. I've never used it as a daily driver...

So in summary, the single and dual port 1600 in the T2A (and first year of T2B) was, in fact, more robust (though slower); well, I say that for 1600cc's of displacement, the doghouse cooling fan was up to the task; the crankshaft was weaker and more prone to pounding out the case, and the magnesium alloy case was inferior... The carbureted 1.7 of '72 and '73 was best for durability (of the type iv engines) due to i) moderate displacement for the pancake engine cooling system; and ii) carburetion which generally was richer (cooler running) than FI buses.

Seems to me that more displacement (than 2 litres) is not very advisable with the type iv, unless other improvements are undertaken.

That Down-the-Middle axial fan system; that may have merit in keeping the heads cool, and properly jetted carburetion versus FI may make things run cooler.

Still sounds to me like VW, when ultimately offering the 2 litre in '76, dropped the ball on cooling system adequacy and cyl head durability. You know, my Kombi is rated for about 2200# payload (more than the typical 1/2 ton p/u of the day), it's governed to 84 mph, it happily drives at 60 mph. If there are no owners manual warnings, well then it reasonably ought not to drop valve seats!

This is all moot; the answer is to just deal with it...

[Abscate]

Awesome build thread.

I’m still left out wondering what an FGI is other than a really good sport.

Orwell, I’ll be at Hunts in Schenectady and will ask about type IV case work. He’s done nice work for me on quirky Volvos and will tell me go/no upfront.

He is a bit seasonal as he does big money Daytona work that you have to work around so he can make money.
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.ssS!

[Xevin]

[orwell84]

I’ve only had valve and seat problems when I really pushed my bus on long hot highway runs. They put out a lot more power than you can reasonably use for sustained highway speeds. They just can’t be driven or maintained like modern cars, but they are not delicate flowers either.

[Clatter]

I'm of a different opinion than some here.

I've seen OEM motors new from VW go 130K in a '79 bus.

If you indeed have only 40K on the vehicle from new,
Not some rebuild with 40K on AMC heads,
That's a whole 'nuther kettle of fish.

All you gotta do is run that.

And make sure it's not leaking at the intake or exhaust,
And tuned right,
Of course..


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Bus Motor Build

What’s That Noise?!?

[Abscate]

+1000 Clatter

Who are you saving it for, anyway?
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.ssS!

[SGKent]

I have heard from some with experience building heads that the AMC castings are generally better than the OG ones. The reason being is that they are not as rigid. While it shows up in more initial valve adjustments as the heads settle in, they are less prone to cracking - which is one of the problems with the OG heads. One thing constantly forgotten is that when these buses were originally being used, the national speed limit was 55 mph and enforced. States that failed to do that lost lots of federal highway funding. Driving 55 - 60 mph down the highway as a top speed was a given most of the time in these buses. Some areas it wasn't obeyed but many areas it was. We see more overheating issues now than then, excepting 1970 and earlier single port engines with the oil cooler that sat over #3, causing a significant number of dropped #3 valve in a desert climate back in those days. Many of those buses that still exist have been converted to dog house coolers for that reason. My engine efficiency went way up with Len's heads compared to the OG heads. Recent smog test shows the engine now is equal to a new early 2000's car as to efficiency. I am getting 15% CO2 and no waste with these new heads. Amazingly clean burn. Head temps are normal for the bus.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Cdn17Sport6MT]

[Cdn17Sport6MT]

[Cdn17Sport6MT]

[Clatter]

Last few days a couple things happened.

Jim finished up flycutting heads and valve job.
Guides on these heads were good enough to leave alone.

These AMC heads are interesting to both of us.
They have '1.8' cast into the bottom, which neither Jim or myself have ever seen.
As well as the peening around the seats.
Jim was guessing that they had been rebuilt.
I'm not so sure.
Peening looks very uniform and exact compared to any I seen before done by some shop.
Mark Stephens used to do similar, for example, didn't look anything like this.

Jim said seats felt soft under the cutter, typical of AMC seats.
The angles don't come out as crisp on the corners as a result.

Flycut was minimal, preserving the step.
I'm guessing, just by cosmic inference perhaps, that these are some newer AMC heads,
And that's all stuff from the factory how they come now.
Anybody know?
We got ourselves a mystery here!


Here's the second set of rods Jim rejected.
These heavy pits didn't show up until they were cleaned.
Should toss these,
But can't for some reason...
They have a 12-step program for this.
I just haven't hit bottom yet.

Here's the rods he rescued from a 2.0 914.
They are beautiful and perfect.
And i love them very much.

Spent some time test-fitting wrist pins over and over just to feel the bliss.
Jim asked me if i noticed how the wrist-pin was fatter in the middle.
Chine pin is slightly barrel-shaped.
Didn't notice that.
Even now that i know it's there..!
Crazy the feel that guy developed after so many years.



Fan got shot-blasted.
Peened surface stays cleaner longer.
Clean fans move more air.

Polished machining marks from thrust-faces of cam.
These are done at Web.
Faces look better than before.
Still something to check.

Stabbed gear and cleaned it up and cam is ready.


Pulled Sparxwerks (very beautiful) SVDA open to bend advance tabs inward a bit.
Did Jeff's a couple days ago and got it perfect first try.
Doing it now while the memory is still fresh.

Installed module.
Factory rev limiter is set to 5500. Perfect.

Finally,
Trying to find a place to vapor-blast a case.
FOUR of these places now gone tits-up on me.
Not an easy buck to make methinks.

Found a couple places over the hill that say they'll do it.
Need to come up with two excuses to drive the hill..
We'll see.
Usually three or four hunnert bux.
"Beauty knows no pain" right?

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Bus Motor Build

What’s That Noise?!?

[tricyclerob]

Certainly the peening is far too uniform to be done by anything other than a dedicated press.

Definitely not some guy with a punch. Mechanically a good idea as long as;

!. doesn't generate "hot spots". [doesn't look like it should]

2. doesn't [didn't] disturb the initial fit of the seat.

3. isn't to compensate for questionable seat fit.

Looks pretty "official" anyway. Maybe someone else has seen this exact peening and can comment.

Rods look great!

[Cdn17Sport6MT]

[SGKent]

the peens were done in the factory with a very large press and tool.
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[tricyclerob]

[Clatter]