All of this prep will pay real results later. Looks great.

Looking great, my friend @pikofix!
You are right about the PEs, they can be a hit or a miss, not all of them are practically useable and some of them look unrealistic in 2D. I remember building a Fonderie-Miniature quarterscale Griffon, where the kit depended a lot in PE for the small parts: well, the PE side pitots were totally unrealistic...

A very nice step-by-step guide is always handy, Csaba.
And I agree with our friend Spiros, some PE parts are a great addition to the build but unfortunately some are better to leave out.

Unfortunately I did not have too much time over the weekend. One more week at work, and I will have time off for a few weeks, I hope I will have a bit time for this kit.
I sanded the fillings made last time, and assembled a few small parts. I also looked at the engines, again. It seems that there is quite a difference between the Eduard and ICM engines. ICM made the engine much smaller than Eduard , and I have no idea which one is correct. I have to find a drawing of the actual M-11 engine to get the correct measurements.
It is always interesting to compare multiple manufacturers, sometimes the difference between the same parts is shocking. I remember once we made a comparison of MiG-21MF ejection seats from three different, well known aftermarket manufacturers. Everything was different, the basic dimensions, proportions, details...

I forgot to mention that I bought the bundle release with the mechanics and pilots. I found it for the same price as the normal boxing, and well, why not to take the free candy, right? I don’t want to build a diorama, but the figures will be great for painting exercises. The figures are from an older ICM kit. There will be a little bit of cleanup needed, but otherwise the figures are excellent for this scale.

3 attached images. Click to enlarge.

Found the diameter of the engine in a 1952 flying magazine. A whole series was published about the M-11 engine, so now I know all of the oil temperatures, magneto types and other weird technical data. If you ever wondered, the oil temperature is 40C at the inlet, and maximum 100C at the outlet. The fuel pump type is BNL-12A and it is driven by a 0,74 ratio reduction drive. 🙂

So, back to modelling - the diameter of the engine is 1075mm, which is 22,4mm in 1:48 scale. Now, how to understand diameter? Another article used the term "width", while giving the same 1075mm data.
If I measure it as diameter (imagine a circle covering the engine) , the ICM engine is correct, if I measure it as width (the distance between two sides of the engines), the Eduard engine is spot on. The 1:48 scale drawings from the Scale Plans book fit the ICM engine.
The Eduard engine looks more detailed, especially because of the cooling fins. However, it requires a small surgery, since it does not fit on the ICM fuselage. It also looks a bit "fat" compared to the reference photos.
I think I will assembly and paint both of the engines, and see which looks better on the finished model.

Regardless of your final choice, I loved your research and foundings, my friend @pikofix!

Other baby step. Made a very simple firewall, no details at all, just to simply block the light going through the fuselage. The carburetor intake will hide most of the opening anyway.
Also made the valve rods from Evergreen. Oversized, but better defined than the original parts. Eduard provided parts on the photo etched sheet, but it is a flat part. You can try to make them more three dimensional with thick paint, but it won’t be the same as a rod.

Yes Erik, diameter makes more sense. I got also surprised to see the term “width” defined for a radial engine. After all, it seems that ICM got the sizes correct.

1 attached image. Click to enlarge.

Nice beby steps, Csaba. The rods look very nice!