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Very nice work. Great to see.

What is the ratio of cam lift to valve lift on the Flaminia rocker arm? It’s 1:1.5 on the Aurelia. Let me know if you need the Aurelia rocker drawing to work with, sorry don’t have the Flaminia.
Geoff
 

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Discussion Starter #482 (Edited)
Very nice work. Great to see.

What is the ratio of cam lift to valve lift on the Flaminia rocker arm? It’s 1:1.5 on the Aurelia. Let me know if you need the Aurelia rocker drawing to work with, sorry don’t have the Flaminia.
Geoff
Geoff, the Aurelia drawing might be helpful just to understand better, compare and check if the measuring turns out "familiar". It is not easy to get correct measures out of a worn 60 year old part.

The vast majority of the Flaminia rockers suffers from flatened "heads". I mean the end pushing the valve. The surface normally is worn out where the arm touches the end of the valve stem while the surface not in touch with the stem remains in original shape. this leads to a step between worn and non worn area making proper adjustment of the valve play difficult and annoying.

The other thing is that the shaft of the rocker wears out as well as does the bearing surface in the rocker arm support.

There are various possibilities of how to make the new parts:

1. original dimensions (leaves open how to handle the worn out rocker supports)
2. oversize shafts (one has to bore the supports to new shaft dia)
3. installation of needle bearings (modified shafts and/or supports)
4. make bearing shells (out of gunmetal) to fit originally dimensioned shafts (with modified supports)

Besides this one could slightly increase the leverage in order to get a little bit more valve lift, no?

Any ideas or advice is welcome!!!

Hubert
 

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Walt Spak used to rebuild these by rechroming the shafts, and reboring the rocker boxes. He did this for Aurelias, and probably Flaminias. The ends were simply raidiused as at that time we didn't know better. Now we have the drawings from Lancia, which show how the ends were defined.
 

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Why Nicasil coated aluminum liners, and not iron?

Pete
 

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Discussion Starter #485
Pete

now that you are asking . . .

Talked to an expert in engine optimizing and he told me that one could reduce the wall thickness using these. The cast iron Flaminia liner has 5 mm thickness, boring to 88 mm would result in 3,5 mm. I missed asking him why alu and not iron.

Requires further investigation :001_unsure::001_unsure::001_unsure:

Hubert
 

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Why reduce the wall thickness? Is there a defect you are trying to solve?

My understanding is that the automotive industry has moved away from coated alloy liners and back to iron or steel.
Pete
 

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Discussion Starter #491
Pete,

thanks for the link. Had some informative conversation with a piston and liner manufacturer. They suggest to try iron liners in the first step. Nicasil coating is about 370 USD per liner, not a bargain, especially when you can get along without it.

Hubert
 

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I suggest option #2.

At Walt Spak's suggestion, I followed suit in my own way. Over-size hard chromed shafts, after a clean-up grind, then all ground to the same size, and honing bores to fit. A torque plate for honing the blocks is needed, or your engine will seize upon start-up (happily no damage besides a bent pushrod, easily replaced...). As you've noticed, there is a lot of pressure on the ends of the shafts, and there is a tendency to galling of the block to the shaft. I think the hard chrome against the forged blocks is a good match (modern coatings MAY help, but I don't know how they wear).

I thought about needle bearings and shell bearings, but it would require hardened surfaces for the needles, and the shells would require a lot of effort to make, and a material that would withstand the pressure better. Both too complicated, even for (a) Lancia.

A friend has/had a jig to grind Flaminia tips, made by Fred Delong, of Delong Cams. I believe it will come my way in the near future, and will share it with you if it happens. I believe the tips were nitrided, evidenced by copper plating I noticed, if I remember correctly. I am curious what the profile was.

Anyway, I'm interested in a set, depending on cost. Do you still have free flow thermostats and radiator ducts in stock (or even the drawing for the ducts)?

-Steve
 

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Discussion Starter #493
I suggest option #2.

At Walt Spak's suggestion, I followed suit in my own way. Over-size hard chromed shafts, after a clean-up grind, then all ground to the same size, and honing bores to fit. A torque plate for honing the blocks is needed, or your engine will seize upon start-up (happily no damage besides a bent pushrod, easily replaced...). As you've noticed, there is a lot of pressure on the ends of the shafts, and there is a tendency to galling of the block to the shaft. I think the hard chrome against the forged blocks is a good match (modern coatings MAY help, but I don't know how they wear).

I thought about needle bearings and shell bearings, but it would require hardened surfaces for the needles, and the shells would require a lot of effort to make, and a material that would withstand the pressure better. Both too complicated, even for (a) Lancia.

A friend has/had a jig to grind Flaminia tips, made by Fred Delong, of Delong Cams. I believe it will come my way in the near future, and will share it with you if it happens. I believe the tips were nitrided, evidenced by copper plating I noticed, if I remember correctly. I am curious what the profile was.

Anyway, I'm interested in a set, depending on cost. Do you still have free flow thermostats and radiator ducts in stock (or even the drawing for the ducts)?

-Steve
You are probably right, all kinds of discrete bearings may require a deep research before designing and then making them will be complicated and reliability will be questionable afterwards.

The part is not trivial, hence I will do some research before starting the production. First of all, some analysis has to be made:

1. rocker box

- determination of material
- sectional cut through the stressed area (hardness depth)
- surface hardness

2. rocker arm

- determination of material
- sectional cut through shaft
- sectional cut through tip
- surface hardness


Will keep you updated. It would be very helpfull, if you´d share the info you have. Thanks in advance!

Thermostats are made every now and then and there are oil circuit thermostats available as well.
Regarding the air duct, if I make one, it will be fairly expensive compared to the simplicity of the finished product. The layout of the duct is simple and I do not mind sharing the design. Will send a sketch or pics with measures, so that you can have one made locally. Anyhow I will make one for you, if you want. Should discuss this via email or pm.
 

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Discussion Starter #494 (Edited)






Some pics of a fairly good rocker arm. The shape seems to be circular to me. The wear shows two more or less plain surfaces, divided by a line which is not worn. At this line the rotation of the arm complies with the movement of the valve stem, before and after the tip is sliding over the stem end, at least that is what I have concluded from the pics. Also interesting to see how Lancia machined the surface of the tip.





The shaft looks quite well, a magnification still shows many scratches. the other pic shows the underside of the shaft which is as it left the factory
 

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If designing a modern replacement, surely a roller rocker would be the way to go.
Pete
 

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Discussion Starter #497 (Edited)
might this be useful for parts? no reserve...
https://bringatrailer.com/listing/lancia-v6/
That is a really nice looking engine. Albeit the 813.00 is of interest for Flaminia Berlina 1st series only. Heavier flywheel, smaller inlet and exhaust valves each with single spring only, weaker rockers . . . all missing here. Anyhow, the heads are accordingly, smaller ports for inlet and outlet.

If thinking of a runner, only the unstamped block and the oil pan would be of interest. They are machined together, therefore should be used as a pair, but then you can make any engine up to 2.5 3C out of them provided nobody notices that the flange for the mechanical fuel pump is there, which it is not on 3B and 3C engines.







Or turn it into the ultimate Flaminia 3.0
 

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yes, it's the block i was thinking might be useful. no corrosion present. new blocks can't be found easily i'd imagine. but then the artwork is lost...
 

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Discussion Starter #499 (Edited)


As the “numbers matching” engine cannot be used without mayor block repair, a 2.8 L (call it the Black Pearl because it is black from dirt) was acquired, planned to be pumped up to 3.0 in the first stage. Dismantling of the Pearl turned out to be difficult. The mess started with the heads. When applying my EHE (EPI-Hexadecimal Extractor), which pulled every head up to now, the only thing being pulled where the rocker support studs, which came out with the thread that should hold them down.
Had been thinking of a second generation EHE for some time, so converted the old one to EHE-EVO I.

Consisting of three parts, it now holds the head with the exhaust header studs, the rocker support studs and the intake manifold studs while still pressing on the studs that fix the head to the block.

Several days of making the components, warming up the head in the critical areas several times, and letting some penetrating oil work it´s wonder and the result is . . . nothing. Except for the variety of blown away and bent bolts.

The most spectacular moment was, when the extractor shot four bolt heads off at the same time.

The studs will have to be removed on the milling machine. As its work depth is too small to take up the whole engine plus the tools and the travel they need, the oil pan was removed in order to get the crankshaft out and gain some space.

How surprised I was detecting the reason why the engine was put out of service back in the day. One of the conrods is heavily bent, one other suffers from a bearing failure.

Anybody out there willing to help me out with one (or better one set of) conrod for 2.8L???




Even the spark plugs won´t go without some controlled brutality.








Strange things to be found in hidden places


Aquatic storage, no good for crankshafts
 

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Looks like you are going to have to cut the heads off. I wonder if this can be done accurately enough that, after installing new head studs the block AND head could be reused after skimming.

The only tool I can think of his a bandsaw and cut where the head gasket is. Hopefully minimal damage to both head and block surfaces, otherwise you will have to choose whether to save the heads or the blocks ...
Pete
 
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